SRNL-STI-2009-00636, Rev. 0, 'Iodine, Neptunium, Plutonium ...SRNL-STI-2009-00636 Revision 0 iv...
Transcript of SRNL-STI-2009-00636, Rev. 0, 'Iodine, Neptunium, Plutonium ...SRNL-STI-2009-00636 Revision 0 iv...
SRNL-STI-2009-00636 Revision 0
Keywords Iodine Neptunium Plutonium Technetium I Np Pu Tc Saltstone Redox Distribution Coefficients Kd Apparent Solubility Values Glovebox Retention Permanent
Iodine Neptunium Plutonium and Technetium Sorption to Saltstone and Cement Formulations
Under Oxidizing and Reducing Conditions
Michael S Lilley(a) Brian A Powell(a) and Daniel I Kaplan
December 16 2009
(a) Department of Environmental Engineering and Earth Sciences Clemson University Clemson SC
Savannah River National Laboratory Savannah River Nuclear Solutions Aiken SC 29808 Prepared for the US Department of Energy under contract number DE-AC09-08SR22470
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DISCLAIMER
This work was prepared under an agreement with and funded by the US Government Neither the US Government or its employees nor any of its contractors subcontractors or their employees makes any express or implied
1 warranty or assumes any legal liability for the accuracy completeness or for the use or results of such use of any information product or process disclosed or 2 representation that such use or results of such use would not infringe privately owned rights or 3 endorsement or recommendation of any specifically identified commercial product process or service
Any views and opinions of authors expressed in this work do not necessarily state or reflect those of the United States Government or its contractors or subcontractors
Printed in the United States of America
Prepared for
US Department of Energy
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EXECUTIVE SUMMARY
Sorption of 99Tc 127I 237Np and 242Pu to two saltstone and two cementitious materials was examined Np and Pu sorbed very strongly to all four cementitious formulations and appeared to reach steady state within 24 h Based on the sorption behavior there were some indications that partial reduction of Pu(IV) to Pu(III) and Np(V) to Np(IV) occurs in these systems However the Kd values for both Pu and Np remain gt105 mLg throughout the experiments This value compares favorably with previously reported Kd values for Pu but is significantly higher than the previously reported value of 3000-4000 mLg for Np (Kaplan et al 2008)
In all experiments regardless of the total concentration of Np and Pu in the system a relatively constant aqueous phase concentration of both Np and Pu was observed Therefore it appears that the aqueous concentrations of Np and Pu are solubility controlled rather than sorption controlled The measured concentrations for Np and Pu ranged from 10-11 molL to 10-13 molL These values are consistent with precipitation of actinide hydrous oxide solid phases consequently these tests strongly suggest that solubility (as described by solubility constants) and not sorption (as described by Kd values) will controlling Np and Pu aqueous concentration near the Saltstone Disposal Facility
Sorption of both Tc and I do not appear to have reached steady state during the four day equilibration times used in these experiments Similar to Np and Pu surface mediated redox processes were affecting Tc and I sorption However this observation was based on changes in sorption behavior not direct determination of Tc or I oxidation states Calculated I Kd values of 766 and 725 mLg for simulated Vault 2 concrete under oxidizing and reducing conditions respectively in the present work compare favorably with values of 894 and 715 mLg under similar conditions reported by Kaplan et al (2008) Although it appears steady state was not reached in Tc systems conditional Kd values were calculated and were found to be a factor of ~5 higher than values previously reported by Kaplan et al (2008) The fraction of reducing slag within each saltstone formulation appears to have an effect on Tc sorption Tc Kd values under oxidizing conditions ranged from 275 to 508 mLg Saltstone formulations under reducing conditions had Kd values between 32 (0 dry wt- slag) and 4370 mLg (45 dry wt- slag) but the system had not achieved steady state conditions at the time of measurement thus greater sorption may likely occur under natural conditions Cementitious formulation did not influence Pu Np or I sorption These data support the following changes in the SRS ldquobest Kdrdquo geochemical data package used as input to SRS performance assessment calculations
Present data (d) This document Stage 1(c)
Young Stage 2 Medium
Stage 3 Old
Stage 1 Young
Stage 2 Medium
Stage 3 Old
Reducing Concrete (mLg) I 5 9 0 5 9 0
Np 4000 4000 3000 10-13 M(a) 10-13 M (a) 5000 Pu 10000 10000 1000 10-12 M (a) 10-12 M (a) 2000 Tc 5000 5000 5000 5000 5000 1000 (b)
Oxidizing Concrete (mLg) I 8 15 4 8 15 4
Np 1600 1600 250 10-12 M (a) 10-12 M (a) 5000 Pu 10000 10000 1000 10-12 M (a) 10-12 M (a) 2000 Tc 08 08 05 08 08 05
(a) Apparent solubility (units = M = molL) Below this concentration Kd value of 10000 mLg is to be used (b) A decrease in Tc Kd values with respect to previous values will be used because of the observation that Tc(IV) oxidizes readily under SRS conditions to Tc(VII) (c) Stages 1 2 and 3 are conceptually based on mineral composition changes The 1st 2n and 3rd stages are expected to last 50 500 and 7000 pore volumes respectively A 2-ft slab of cement may be expected to last 740 yr in the 1st stage 7400 yr in the 2nd and 103600 yr in the 3rd stage (d) Kaplan (2007) Kaplan and Coates (2008) and Kaplan et al 2008
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TABLE OF CONTENTS
10 Introduction 15 20 Objectives 15 30 Materials and Methods 15
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions 15 311 242Pu 15 312 237Np 16 313 99Tc 17 314 127I 18 315 Cementitious Materials Selected for Experiments 19
32 ICP-MS Detection Limits 20 33 Experimental Methods 20 34 Experimental Protocol for Sorption Experiments under Aerobic Conditions 21 35 Experimental Protocol for Sorption Experiments under Anerobic Conditions 22 36 Examination of Sorption to Vial Walls for Solids and No Solids Controls 23 37 Data Analysis 23
40 Results and Discussion 24 41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions 24 42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions 28 43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions 32 44 Radionuclide Sorption to Vial Walls under Reducing Conditions 38
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions 40 60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions46 70 Summary and Recommendations for Future Work 48
71 Comparison with Previous Data 48 72 Suggested Future Work 48
80 References 49 90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions 51
91 Data Tables for No Solid Controls 51 92 Data Tables for Vault 2 54 93 Data tables for saltstone TR545 57 94 Data Tables for Saltstone TR547 59
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95 Data Tables for Aged Cement 62 96 Data Tables for Sorption to Vial Walls 65
100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions 66 101 Data Tables for No-Solid Controls 66 102 Data Tables for Vault 2 69 103 Data Tables for TR545 72 104 Data Tables for TR547 75 105 Data Tables for Aged Cement 78 106 Data Tables for Sorption to Vial Walls 80
110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone
Property Testing SRNL L3100-2009-00019 Rev 0 82
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LIST OF TABLES
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008) 19
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS 20
Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions 22
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions 46
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions 47
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions 47
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions 48
Table 91 Plutonium no solids control after one day 51
Table 92 Plutonium no solids control after four days 51
Table 93 Neptunium no solids control after one day 52
Table 94 Neptunium no solids control after four days 52
Table 95 Technetium no solids control after one day 52
Table 96 Technetium no solids control after four days 53
Table 97 Iodine no solids control after one day 53
Table 98 Iodine no solids control after four days 53
Table 99 Vault 2- plutonium after one day 54
Table 910 Vault 2- plutonium after four days 54
Table 911 Vault 2- neptunium after one day 54
Table 912 Vault 2- neptunium after four days 55
Table 913 Vault 2- technetium after one day 55
Table 914 Vault 2- technetium after four days 55
Table 915 Vault 2- iodine after one day 56
Table 916 Vault 2- iodine after four days 56
Table 917 TR545- plutonium after one day 56
Table 918 TR545- plutonium after four days 57
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Table 919 TR545- neptunium after one day 57
Table 920 TR545- neptunium after four days 57
Table 921 TR545- technetium after one day 58
Table 922 TR545- technetium after four days 58
Table 923 TR545- iodine after one day 58
Table 924 TR545- iodine after four days 59
Table 925 TR547- plutonium after one day 59
Table 926 TR547- plutonium after four days 60
Table 927 TR547- neptunium after one day 60
Table 928 TR547- neptunium after four days 60
Table 929 TR547- technetium after one day 61
Table 930 TR547- technetium after four days 61
Table 931 TR547- iodine after one day 61
Table 932 TR547- iodine after four days 62
Table 933 Aged cement- plutonium after one day 62
Table 934 Aged cement- plutonium after four days 63
Table 935 Aged cement- neptunium after one day 63
Table 936 Aged cement- neptunium after four days 63
Table 937 Aged cement- technetium after one day 64
Table 938 Aged cement- technetium after four days 64
Table 939 Aged cement- iodine after one day 64
Table 940 Aged cement- iodine after four days 65
Table 941 Plutonium sorbed to vial wall in no solids control 65
Table 942 Neptunium sorbed to vial wall in no solids control 65
Table 101 Plutonium no solids control after one day 66
Table 102 Plutonium no solids control after four days 67
Table 103 Neptunium no solids control after one day 67
Table 104 Neptunium no solids control after four days 67
Table 105 Technetium no solids control after one day 67
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Table 106 Technetium no solids control after four days 68
Table 107 Iodine no solids control after one day 68
Table 108 Iodine no solids control after four days 68
Table 109 Vault 2- plutonium after one day 69
Table 1010 Vault 2- plutonium after four days 69
Table 1011 Vault 2- neptunium after one day 70
Table 1012 Vault 2- neptunium after four days 70
Table 1013 Vault 2- technetium after one day 70
Table 1014 Vault 2- technetium after four days 71
Table 1015 Vault 2- iodine after one day 71
Table 1016 Vault 2- iodine after four days 71
Table 1017 TR545- plutonium after one day 72
Table 1018 TR545- plutonium after four days 72
Table 1019 TR545- neptunium after one day 73
Table 1020 TR545- neptunium after four days 73
Table 1021 TR545- technetium after one day 73
Table 1022 TR545- technetium after four days 74
Table 1023 TR545- iodine after one day 74
Table 1024 TR545- iodine after four days 74
Table 1025 TR547- plutonium after one day 75
Table 1026 TR547- plutonium after four days 75
Table 1027 TR547- neptunium after one day 76
Table 1028 TR547- neptunium after four days 76
Table 1029 TR547- technetium after one day 76
Table 1030 TR547- technetium after four days 77
Table 1031 TR547- iodine after one day 77
Table 1032 TR547- iodine after four days 77
Table 1033 Aged cement- plutonium after one day 78
Table 1034 Aged cement- plutonium after four days 78
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Table 1035 Aged cement- neptunium after one day 78
Table 1036 Aged cement- neptunium after four days 79
Table 1037 Aged cement- technetium after one day 79
Table 1038 Aged cement- technetium after four days 79
Table 1039 Aged cement- iodine after one day 80
Table 1040 Aged cement- iodine after four days 80
Table 1041 Plutonium sorbed to vial wall in no solids control 80
Table 1042 Neptunium sorbed to vial wall in no solids control 81
Table 1043 Technetium sorbed to vial wall in no solids control 81
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LIST OF FIGURES
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb 16
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb 17
Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb 18
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb 19
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples 25
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 25
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background 26
Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation 27
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation
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of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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19
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
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solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
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As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
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Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
SRNL-STI-2009-00636 Revision 0
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
SRNL-STI-2009-00636 Revision 0
37
The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
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38
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
SRNL-STI-2009-00636 Revision 0
39
and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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40
under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
SRNL-STI-2009-00636 Revision 0
41
whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
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42
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
43
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
44
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
45
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
46
60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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47
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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48
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
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49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
SRNL-STI-2009-00636 Revision 0
50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
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51
90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
SRNL-STI-2009-00636 Revision 0
52
Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
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53
Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
SRNL-STI-2009-00636 Revision 0
54
92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
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Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
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Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
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93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
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Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
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Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
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Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)
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EXECUTIVE SUMMARY
Sorption of 99Tc 127I 237Np and 242Pu to two saltstone and two cementitious materials was examined Np and Pu sorbed very strongly to all four cementitious formulations and appeared to reach steady state within 24 h Based on the sorption behavior there were some indications that partial reduction of Pu(IV) to Pu(III) and Np(V) to Np(IV) occurs in these systems However the Kd values for both Pu and Np remain gt105 mLg throughout the experiments This value compares favorably with previously reported Kd values for Pu but is significantly higher than the previously reported value of 3000-4000 mLg for Np (Kaplan et al 2008)
In all experiments regardless of the total concentration of Np and Pu in the system a relatively constant aqueous phase concentration of both Np and Pu was observed Therefore it appears that the aqueous concentrations of Np and Pu are solubility controlled rather than sorption controlled The measured concentrations for Np and Pu ranged from 10-11 molL to 10-13 molL These values are consistent with precipitation of actinide hydrous oxide solid phases consequently these tests strongly suggest that solubility (as described by solubility constants) and not sorption (as described by Kd values) will controlling Np and Pu aqueous concentration near the Saltstone Disposal Facility
Sorption of both Tc and I do not appear to have reached steady state during the four day equilibration times used in these experiments Similar to Np and Pu surface mediated redox processes were affecting Tc and I sorption However this observation was based on changes in sorption behavior not direct determination of Tc or I oxidation states Calculated I Kd values of 766 and 725 mLg for simulated Vault 2 concrete under oxidizing and reducing conditions respectively in the present work compare favorably with values of 894 and 715 mLg under similar conditions reported by Kaplan et al (2008) Although it appears steady state was not reached in Tc systems conditional Kd values were calculated and were found to be a factor of ~5 higher than values previously reported by Kaplan et al (2008) The fraction of reducing slag within each saltstone formulation appears to have an effect on Tc sorption Tc Kd values under oxidizing conditions ranged from 275 to 508 mLg Saltstone formulations under reducing conditions had Kd values between 32 (0 dry wt- slag) and 4370 mLg (45 dry wt- slag) but the system had not achieved steady state conditions at the time of measurement thus greater sorption may likely occur under natural conditions Cementitious formulation did not influence Pu Np or I sorption These data support the following changes in the SRS ldquobest Kdrdquo geochemical data package used as input to SRS performance assessment calculations
Present data (d) This document Stage 1(c)
Young Stage 2 Medium
Stage 3 Old
Stage 1 Young
Stage 2 Medium
Stage 3 Old
Reducing Concrete (mLg) I 5 9 0 5 9 0
Np 4000 4000 3000 10-13 M(a) 10-13 M (a) 5000 Pu 10000 10000 1000 10-12 M (a) 10-12 M (a) 2000 Tc 5000 5000 5000 5000 5000 1000 (b)
Oxidizing Concrete (mLg) I 8 15 4 8 15 4
Np 1600 1600 250 10-12 M (a) 10-12 M (a) 5000 Pu 10000 10000 1000 10-12 M (a) 10-12 M (a) 2000 Tc 08 08 05 08 08 05
(a) Apparent solubility (units = M = molL) Below this concentration Kd value of 10000 mLg is to be used (b) A decrease in Tc Kd values with respect to previous values will be used because of the observation that Tc(IV) oxidizes readily under SRS conditions to Tc(VII) (c) Stages 1 2 and 3 are conceptually based on mineral composition changes The 1st 2n and 3rd stages are expected to last 50 500 and 7000 pore volumes respectively A 2-ft slab of cement may be expected to last 740 yr in the 1st stage 7400 yr in the 2nd and 103600 yr in the 3rd stage (d) Kaplan (2007) Kaplan and Coates (2008) and Kaplan et al 2008
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TABLE OF CONTENTS
10 Introduction 15 20 Objectives 15 30 Materials and Methods 15
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions 15 311 242Pu 15 312 237Np 16 313 99Tc 17 314 127I 18 315 Cementitious Materials Selected for Experiments 19
32 ICP-MS Detection Limits 20 33 Experimental Methods 20 34 Experimental Protocol for Sorption Experiments under Aerobic Conditions 21 35 Experimental Protocol for Sorption Experiments under Anerobic Conditions 22 36 Examination of Sorption to Vial Walls for Solids and No Solids Controls 23 37 Data Analysis 23
40 Results and Discussion 24 41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions 24 42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions 28 43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions 32 44 Radionuclide Sorption to Vial Walls under Reducing Conditions 38
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions 40 60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions46 70 Summary and Recommendations for Future Work 48
71 Comparison with Previous Data 48 72 Suggested Future Work 48
80 References 49 90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions 51
91 Data Tables for No Solid Controls 51 92 Data Tables for Vault 2 54 93 Data tables for saltstone TR545 57 94 Data Tables for Saltstone TR547 59
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95 Data Tables for Aged Cement 62 96 Data Tables for Sorption to Vial Walls 65
100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions 66 101 Data Tables for No-Solid Controls 66 102 Data Tables for Vault 2 69 103 Data Tables for TR545 72 104 Data Tables for TR547 75 105 Data Tables for Aged Cement 78 106 Data Tables for Sorption to Vial Walls 80
110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone
Property Testing SRNL L3100-2009-00019 Rev 0 82
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LIST OF TABLES
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008) 19
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS 20
Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions 22
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions 46
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions 47
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions 47
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions 48
Table 91 Plutonium no solids control after one day 51
Table 92 Plutonium no solids control after four days 51
Table 93 Neptunium no solids control after one day 52
Table 94 Neptunium no solids control after four days 52
Table 95 Technetium no solids control after one day 52
Table 96 Technetium no solids control after four days 53
Table 97 Iodine no solids control after one day 53
Table 98 Iodine no solids control after four days 53
Table 99 Vault 2- plutonium after one day 54
Table 910 Vault 2- plutonium after four days 54
Table 911 Vault 2- neptunium after one day 54
Table 912 Vault 2- neptunium after four days 55
Table 913 Vault 2- technetium after one day 55
Table 914 Vault 2- technetium after four days 55
Table 915 Vault 2- iodine after one day 56
Table 916 Vault 2- iodine after four days 56
Table 917 TR545- plutonium after one day 56
Table 918 TR545- plutonium after four days 57
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Table 919 TR545- neptunium after one day 57
Table 920 TR545- neptunium after four days 57
Table 921 TR545- technetium after one day 58
Table 922 TR545- technetium after four days 58
Table 923 TR545- iodine after one day 58
Table 924 TR545- iodine after four days 59
Table 925 TR547- plutonium after one day 59
Table 926 TR547- plutonium after four days 60
Table 927 TR547- neptunium after one day 60
Table 928 TR547- neptunium after four days 60
Table 929 TR547- technetium after one day 61
Table 930 TR547- technetium after four days 61
Table 931 TR547- iodine after one day 61
Table 932 TR547- iodine after four days 62
Table 933 Aged cement- plutonium after one day 62
Table 934 Aged cement- plutonium after four days 63
Table 935 Aged cement- neptunium after one day 63
Table 936 Aged cement- neptunium after four days 63
Table 937 Aged cement- technetium after one day 64
Table 938 Aged cement- technetium after four days 64
Table 939 Aged cement- iodine after one day 64
Table 940 Aged cement- iodine after four days 65
Table 941 Plutonium sorbed to vial wall in no solids control 65
Table 942 Neptunium sorbed to vial wall in no solids control 65
Table 101 Plutonium no solids control after one day 66
Table 102 Plutonium no solids control after four days 67
Table 103 Neptunium no solids control after one day 67
Table 104 Neptunium no solids control after four days 67
Table 105 Technetium no solids control after one day 67
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Table 106 Technetium no solids control after four days 68
Table 107 Iodine no solids control after one day 68
Table 108 Iodine no solids control after four days 68
Table 109 Vault 2- plutonium after one day 69
Table 1010 Vault 2- plutonium after four days 69
Table 1011 Vault 2- neptunium after one day 70
Table 1012 Vault 2- neptunium after four days 70
Table 1013 Vault 2- technetium after one day 70
Table 1014 Vault 2- technetium after four days 71
Table 1015 Vault 2- iodine after one day 71
Table 1016 Vault 2- iodine after four days 71
Table 1017 TR545- plutonium after one day 72
Table 1018 TR545- plutonium after four days 72
Table 1019 TR545- neptunium after one day 73
Table 1020 TR545- neptunium after four days 73
Table 1021 TR545- technetium after one day 73
Table 1022 TR545- technetium after four days 74
Table 1023 TR545- iodine after one day 74
Table 1024 TR545- iodine after four days 74
Table 1025 TR547- plutonium after one day 75
Table 1026 TR547- plutonium after four days 75
Table 1027 TR547- neptunium after one day 76
Table 1028 TR547- neptunium after four days 76
Table 1029 TR547- technetium after one day 76
Table 1030 TR547- technetium after four days 77
Table 1031 TR547- iodine after one day 77
Table 1032 TR547- iodine after four days 77
Table 1033 Aged cement- plutonium after one day 78
Table 1034 Aged cement- plutonium after four days 78
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Table 1035 Aged cement- neptunium after one day 78
Table 1036 Aged cement- neptunium after four days 79
Table 1037 Aged cement- technetium after one day 79
Table 1038 Aged cement- technetium after four days 79
Table 1039 Aged cement- iodine after one day 80
Table 1040 Aged cement- iodine after four days 80
Table 1041 Plutonium sorbed to vial wall in no solids control 80
Table 1042 Neptunium sorbed to vial wall in no solids control 81
Table 1043 Technetium sorbed to vial wall in no solids control 81
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LIST OF FIGURES
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb 16
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb 17
Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb 18
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb 19
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples 25
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 25
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background 26
Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation 27
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation
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of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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17
concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
SRNL-STI-2009-00636 Revision 0
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solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
SRNL-STI-2009-00636 Revision 0
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
SRNL-STI-2009-00636 Revision 0
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As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
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31
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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34
seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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36
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
SRNL-STI-2009-00636 Revision 0
37
The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
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38
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
SRNL-STI-2009-00636 Revision 0
39
and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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40
under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
SRNL-STI-2009-00636 Revision 0
41
whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
SRNL-STI-2009-00636 Revision 0
42
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
43
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
44
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
45
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
46
60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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47
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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48
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
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49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
SRNL-STI-2009-00636 Revision 0
50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
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90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
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Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
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Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
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92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
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Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
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Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
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93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
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Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
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Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
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Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)
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TABLE OF CONTENTS
10 Introduction 15 20 Objectives 15 30 Materials and Methods 15
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions 15 311 242Pu 15 312 237Np 16 313 99Tc 17 314 127I 18 315 Cementitious Materials Selected for Experiments 19
32 ICP-MS Detection Limits 20 33 Experimental Methods 20 34 Experimental Protocol for Sorption Experiments under Aerobic Conditions 21 35 Experimental Protocol for Sorption Experiments under Anerobic Conditions 22 36 Examination of Sorption to Vial Walls for Solids and No Solids Controls 23 37 Data Analysis 23
40 Results and Discussion 24 41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions 24 42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions 28 43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions 32 44 Radionuclide Sorption to Vial Walls under Reducing Conditions 38
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions 40 60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions46 70 Summary and Recommendations for Future Work 48
71 Comparison with Previous Data 48 72 Suggested Future Work 48
80 References 49 90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions 51
91 Data Tables for No Solid Controls 51 92 Data Tables for Vault 2 54 93 Data tables for saltstone TR545 57 94 Data Tables for Saltstone TR547 59
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95 Data Tables for Aged Cement 62 96 Data Tables for Sorption to Vial Walls 65
100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions 66 101 Data Tables for No-Solid Controls 66 102 Data Tables for Vault 2 69 103 Data Tables for TR545 72 104 Data Tables for TR547 75 105 Data Tables for Aged Cement 78 106 Data Tables for Sorption to Vial Walls 80
110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone
Property Testing SRNL L3100-2009-00019 Rev 0 82
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LIST OF TABLES
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008) 19
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS 20
Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions 22
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions 46
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions 47
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions 47
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions 48
Table 91 Plutonium no solids control after one day 51
Table 92 Plutonium no solids control after four days 51
Table 93 Neptunium no solids control after one day 52
Table 94 Neptunium no solids control after four days 52
Table 95 Technetium no solids control after one day 52
Table 96 Technetium no solids control after four days 53
Table 97 Iodine no solids control after one day 53
Table 98 Iodine no solids control after four days 53
Table 99 Vault 2- plutonium after one day 54
Table 910 Vault 2- plutonium after four days 54
Table 911 Vault 2- neptunium after one day 54
Table 912 Vault 2- neptunium after four days 55
Table 913 Vault 2- technetium after one day 55
Table 914 Vault 2- technetium after four days 55
Table 915 Vault 2- iodine after one day 56
Table 916 Vault 2- iodine after four days 56
Table 917 TR545- plutonium after one day 56
Table 918 TR545- plutonium after four days 57
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Table 919 TR545- neptunium after one day 57
Table 920 TR545- neptunium after four days 57
Table 921 TR545- technetium after one day 58
Table 922 TR545- technetium after four days 58
Table 923 TR545- iodine after one day 58
Table 924 TR545- iodine after four days 59
Table 925 TR547- plutonium after one day 59
Table 926 TR547- plutonium after four days 60
Table 927 TR547- neptunium after one day 60
Table 928 TR547- neptunium after four days 60
Table 929 TR547- technetium after one day 61
Table 930 TR547- technetium after four days 61
Table 931 TR547- iodine after one day 61
Table 932 TR547- iodine after four days 62
Table 933 Aged cement- plutonium after one day 62
Table 934 Aged cement- plutonium after four days 63
Table 935 Aged cement- neptunium after one day 63
Table 936 Aged cement- neptunium after four days 63
Table 937 Aged cement- technetium after one day 64
Table 938 Aged cement- technetium after four days 64
Table 939 Aged cement- iodine after one day 64
Table 940 Aged cement- iodine after four days 65
Table 941 Plutonium sorbed to vial wall in no solids control 65
Table 942 Neptunium sorbed to vial wall in no solids control 65
Table 101 Plutonium no solids control after one day 66
Table 102 Plutonium no solids control after four days 67
Table 103 Neptunium no solids control after one day 67
Table 104 Neptunium no solids control after four days 67
Table 105 Technetium no solids control after one day 67
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Table 106 Technetium no solids control after four days 68
Table 107 Iodine no solids control after one day 68
Table 108 Iodine no solids control after four days 68
Table 109 Vault 2- plutonium after one day 69
Table 1010 Vault 2- plutonium after four days 69
Table 1011 Vault 2- neptunium after one day 70
Table 1012 Vault 2- neptunium after four days 70
Table 1013 Vault 2- technetium after one day 70
Table 1014 Vault 2- technetium after four days 71
Table 1015 Vault 2- iodine after one day 71
Table 1016 Vault 2- iodine after four days 71
Table 1017 TR545- plutonium after one day 72
Table 1018 TR545- plutonium after four days 72
Table 1019 TR545- neptunium after one day 73
Table 1020 TR545- neptunium after four days 73
Table 1021 TR545- technetium after one day 73
Table 1022 TR545- technetium after four days 74
Table 1023 TR545- iodine after one day 74
Table 1024 TR545- iodine after four days 74
Table 1025 TR547- plutonium after one day 75
Table 1026 TR547- plutonium after four days 75
Table 1027 TR547- neptunium after one day 76
Table 1028 TR547- neptunium after four days 76
Table 1029 TR547- technetium after one day 76
Table 1030 TR547- technetium after four days 77
Table 1031 TR547- iodine after one day 77
Table 1032 TR547- iodine after four days 77
Table 1033 Aged cement- plutonium after one day 78
Table 1034 Aged cement- plutonium after four days 78
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Table 1035 Aged cement- neptunium after one day 78
Table 1036 Aged cement- neptunium after four days 79
Table 1037 Aged cement- technetium after one day 79
Table 1038 Aged cement- technetium after four days 79
Table 1039 Aged cement- iodine after one day 80
Table 1040 Aged cement- iodine after four days 80
Table 1041 Plutonium sorbed to vial wall in no solids control 80
Table 1042 Neptunium sorbed to vial wall in no solids control 81
Table 1043 Technetium sorbed to vial wall in no solids control 81
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LIST OF FIGURES
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb 16
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb 17
Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb 18
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb 19
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples 25
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 25
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background 26
Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation 27
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation
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of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
SRNL-STI-2009-00636 Revision 0
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solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
SRNL-STI-2009-00636 Revision 0
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
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As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
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Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
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The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
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38
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
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39
and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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40
under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
SRNL-STI-2009-00636 Revision 0
41
whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
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42
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
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43
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
44
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
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45
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
46
60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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47
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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48
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
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49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
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50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
SRNL-STI-2009-00636 Revision 0
51
90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
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Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
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Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
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92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
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Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
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Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
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93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
SRNL-STI-2009-00636 Revision 0
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
SRNL-STI-2009-00636 Revision 0
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Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
SRNL-STI-2009-00636 Revision 0
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Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
SRNL-STI-2009-00636 Revision 0
61
Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
SRNL-STI-2009-00636 Revision 0
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)
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95 Data Tables for Aged Cement 62 96 Data Tables for Sorption to Vial Walls 65
100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions 66 101 Data Tables for No-Solid Controls 66 102 Data Tables for Vault 2 69 103 Data Tables for TR545 72 104 Data Tables for TR547 75 105 Data Tables for Aged Cement 78 106 Data Tables for Sorption to Vial Walls 80
110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone
Property Testing SRNL L3100-2009-00019 Rev 0 82
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LIST OF TABLES
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008) 19
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS 20
Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions 22
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions 46
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions 47
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions 47
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions 48
Table 91 Plutonium no solids control after one day 51
Table 92 Plutonium no solids control after four days 51
Table 93 Neptunium no solids control after one day 52
Table 94 Neptunium no solids control after four days 52
Table 95 Technetium no solids control after one day 52
Table 96 Technetium no solids control after four days 53
Table 97 Iodine no solids control after one day 53
Table 98 Iodine no solids control after four days 53
Table 99 Vault 2- plutonium after one day 54
Table 910 Vault 2- plutonium after four days 54
Table 911 Vault 2- neptunium after one day 54
Table 912 Vault 2- neptunium after four days 55
Table 913 Vault 2- technetium after one day 55
Table 914 Vault 2- technetium after four days 55
Table 915 Vault 2- iodine after one day 56
Table 916 Vault 2- iodine after four days 56
Table 917 TR545- plutonium after one day 56
Table 918 TR545- plutonium after four days 57
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Table 919 TR545- neptunium after one day 57
Table 920 TR545- neptunium after four days 57
Table 921 TR545- technetium after one day 58
Table 922 TR545- technetium after four days 58
Table 923 TR545- iodine after one day 58
Table 924 TR545- iodine after four days 59
Table 925 TR547- plutonium after one day 59
Table 926 TR547- plutonium after four days 60
Table 927 TR547- neptunium after one day 60
Table 928 TR547- neptunium after four days 60
Table 929 TR547- technetium after one day 61
Table 930 TR547- technetium after four days 61
Table 931 TR547- iodine after one day 61
Table 932 TR547- iodine after four days 62
Table 933 Aged cement- plutonium after one day 62
Table 934 Aged cement- plutonium after four days 63
Table 935 Aged cement- neptunium after one day 63
Table 936 Aged cement- neptunium after four days 63
Table 937 Aged cement- technetium after one day 64
Table 938 Aged cement- technetium after four days 64
Table 939 Aged cement- iodine after one day 64
Table 940 Aged cement- iodine after four days 65
Table 941 Plutonium sorbed to vial wall in no solids control 65
Table 942 Neptunium sorbed to vial wall in no solids control 65
Table 101 Plutonium no solids control after one day 66
Table 102 Plutonium no solids control after four days 67
Table 103 Neptunium no solids control after one day 67
Table 104 Neptunium no solids control after four days 67
Table 105 Technetium no solids control after one day 67
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Table 106 Technetium no solids control after four days 68
Table 107 Iodine no solids control after one day 68
Table 108 Iodine no solids control after four days 68
Table 109 Vault 2- plutonium after one day 69
Table 1010 Vault 2- plutonium after four days 69
Table 1011 Vault 2- neptunium after one day 70
Table 1012 Vault 2- neptunium after four days 70
Table 1013 Vault 2- technetium after one day 70
Table 1014 Vault 2- technetium after four days 71
Table 1015 Vault 2- iodine after one day 71
Table 1016 Vault 2- iodine after four days 71
Table 1017 TR545- plutonium after one day 72
Table 1018 TR545- plutonium after four days 72
Table 1019 TR545- neptunium after one day 73
Table 1020 TR545- neptunium after four days 73
Table 1021 TR545- technetium after one day 73
Table 1022 TR545- technetium after four days 74
Table 1023 TR545- iodine after one day 74
Table 1024 TR545- iodine after four days 74
Table 1025 TR547- plutonium after one day 75
Table 1026 TR547- plutonium after four days 75
Table 1027 TR547- neptunium after one day 76
Table 1028 TR547- neptunium after four days 76
Table 1029 TR547- technetium after one day 76
Table 1030 TR547- technetium after four days 77
Table 1031 TR547- iodine after one day 77
Table 1032 TR547- iodine after four days 77
Table 1033 Aged cement- plutonium after one day 78
Table 1034 Aged cement- plutonium after four days 78
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Table 1035 Aged cement- neptunium after one day 78
Table 1036 Aged cement- neptunium after four days 79
Table 1037 Aged cement- technetium after one day 79
Table 1038 Aged cement- technetium after four days 79
Table 1039 Aged cement- iodine after one day 80
Table 1040 Aged cement- iodine after four days 80
Table 1041 Plutonium sorbed to vial wall in no solids control 80
Table 1042 Neptunium sorbed to vial wall in no solids control 81
Table 1043 Technetium sorbed to vial wall in no solids control 81
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LIST OF FIGURES
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb 16
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb 17
Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb 18
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb 19
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples 25
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 25
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background 26
Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation 27
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation
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of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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15
10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
SRNL-STI-2009-00636 Revision 0
24
solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
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As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
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Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
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The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
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Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
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39
and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
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whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
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42
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
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43
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
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44
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
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45
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
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46
60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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48
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
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49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
SRNL-STI-2009-00636 Revision 0
50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
SRNL-STI-2009-00636 Revision 0
51
90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
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Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
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Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
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92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
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Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
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Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
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93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
SRNL-STI-2009-00636 Revision 0
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
SRNL-STI-2009-00636 Revision 0
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Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
SRNL-STI-2009-00636 Revision 0
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Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
SRNL-STI-2009-00636 Revision 0
61
Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
SRNL-STI-2009-00636 Revision 0
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)
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LIST OF TABLES
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008) 19
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS 20
Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions 22
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions 46
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions 47
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions 47
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions 48
Table 91 Plutonium no solids control after one day 51
Table 92 Plutonium no solids control after four days 51
Table 93 Neptunium no solids control after one day 52
Table 94 Neptunium no solids control after four days 52
Table 95 Technetium no solids control after one day 52
Table 96 Technetium no solids control after four days 53
Table 97 Iodine no solids control after one day 53
Table 98 Iodine no solids control after four days 53
Table 99 Vault 2- plutonium after one day 54
Table 910 Vault 2- plutonium after four days 54
Table 911 Vault 2- neptunium after one day 54
Table 912 Vault 2- neptunium after four days 55
Table 913 Vault 2- technetium after one day 55
Table 914 Vault 2- technetium after four days 55
Table 915 Vault 2- iodine after one day 56
Table 916 Vault 2- iodine after four days 56
Table 917 TR545- plutonium after one day 56
Table 918 TR545- plutonium after four days 57
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Table 919 TR545- neptunium after one day 57
Table 920 TR545- neptunium after four days 57
Table 921 TR545- technetium after one day 58
Table 922 TR545- technetium after four days 58
Table 923 TR545- iodine after one day 58
Table 924 TR545- iodine after four days 59
Table 925 TR547- plutonium after one day 59
Table 926 TR547- plutonium after four days 60
Table 927 TR547- neptunium after one day 60
Table 928 TR547- neptunium after four days 60
Table 929 TR547- technetium after one day 61
Table 930 TR547- technetium after four days 61
Table 931 TR547- iodine after one day 61
Table 932 TR547- iodine after four days 62
Table 933 Aged cement- plutonium after one day 62
Table 934 Aged cement- plutonium after four days 63
Table 935 Aged cement- neptunium after one day 63
Table 936 Aged cement- neptunium after four days 63
Table 937 Aged cement- technetium after one day 64
Table 938 Aged cement- technetium after four days 64
Table 939 Aged cement- iodine after one day 64
Table 940 Aged cement- iodine after four days 65
Table 941 Plutonium sorbed to vial wall in no solids control 65
Table 942 Neptunium sorbed to vial wall in no solids control 65
Table 101 Plutonium no solids control after one day 66
Table 102 Plutonium no solids control after four days 67
Table 103 Neptunium no solids control after one day 67
Table 104 Neptunium no solids control after four days 67
Table 105 Technetium no solids control after one day 67
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Table 106 Technetium no solids control after four days 68
Table 107 Iodine no solids control after one day 68
Table 108 Iodine no solids control after four days 68
Table 109 Vault 2- plutonium after one day 69
Table 1010 Vault 2- plutonium after four days 69
Table 1011 Vault 2- neptunium after one day 70
Table 1012 Vault 2- neptunium after four days 70
Table 1013 Vault 2- technetium after one day 70
Table 1014 Vault 2- technetium after four days 71
Table 1015 Vault 2- iodine after one day 71
Table 1016 Vault 2- iodine after four days 71
Table 1017 TR545- plutonium after one day 72
Table 1018 TR545- plutonium after four days 72
Table 1019 TR545- neptunium after one day 73
Table 1020 TR545- neptunium after four days 73
Table 1021 TR545- technetium after one day 73
Table 1022 TR545- technetium after four days 74
Table 1023 TR545- iodine after one day 74
Table 1024 TR545- iodine after four days 74
Table 1025 TR547- plutonium after one day 75
Table 1026 TR547- plutonium after four days 75
Table 1027 TR547- neptunium after one day 76
Table 1028 TR547- neptunium after four days 76
Table 1029 TR547- technetium after one day 76
Table 1030 TR547- technetium after four days 77
Table 1031 TR547- iodine after one day 77
Table 1032 TR547- iodine after four days 77
Table 1033 Aged cement- plutonium after one day 78
Table 1034 Aged cement- plutonium after four days 78
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Table 1035 Aged cement- neptunium after one day 78
Table 1036 Aged cement- neptunium after four days 79
Table 1037 Aged cement- technetium after one day 79
Table 1038 Aged cement- technetium after four days 79
Table 1039 Aged cement- iodine after one day 80
Table 1040 Aged cement- iodine after four days 80
Table 1041 Plutonium sorbed to vial wall in no solids control 80
Table 1042 Neptunium sorbed to vial wall in no solids control 81
Table 1043 Technetium sorbed to vial wall in no solids control 81
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LIST OF FIGURES
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb 16
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb 17
Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb 18
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb 19
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples 25
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 25
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background 26
Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation 27
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation
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of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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15
10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
SRNL-STI-2009-00636 Revision 0
24
solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
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As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
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Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
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The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
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Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
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39
and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
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whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
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42
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
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43
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
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44
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
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45
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
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46
60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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48
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
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49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
SRNL-STI-2009-00636 Revision 0
50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
SRNL-STI-2009-00636 Revision 0
51
90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
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Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
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Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
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92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
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Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
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Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
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93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
SRNL-STI-2009-00636 Revision 0
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
SRNL-STI-2009-00636 Revision 0
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Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
SRNL-STI-2009-00636 Revision 0
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Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
SRNL-STI-2009-00636 Revision 0
61
Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
SRNL-STI-2009-00636 Revision 0
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)
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Table 919 TR545- neptunium after one day 57
Table 920 TR545- neptunium after four days 57
Table 921 TR545- technetium after one day 58
Table 922 TR545- technetium after four days 58
Table 923 TR545- iodine after one day 58
Table 924 TR545- iodine after four days 59
Table 925 TR547- plutonium after one day 59
Table 926 TR547- plutonium after four days 60
Table 927 TR547- neptunium after one day 60
Table 928 TR547- neptunium after four days 60
Table 929 TR547- technetium after one day 61
Table 930 TR547- technetium after four days 61
Table 931 TR547- iodine after one day 61
Table 932 TR547- iodine after four days 62
Table 933 Aged cement- plutonium after one day 62
Table 934 Aged cement- plutonium after four days 63
Table 935 Aged cement- neptunium after one day 63
Table 936 Aged cement- neptunium after four days 63
Table 937 Aged cement- technetium after one day 64
Table 938 Aged cement- technetium after four days 64
Table 939 Aged cement- iodine after one day 64
Table 940 Aged cement- iodine after four days 65
Table 941 Plutonium sorbed to vial wall in no solids control 65
Table 942 Neptunium sorbed to vial wall in no solids control 65
Table 101 Plutonium no solids control after one day 66
Table 102 Plutonium no solids control after four days 67
Table 103 Neptunium no solids control after one day 67
Table 104 Neptunium no solids control after four days 67
Table 105 Technetium no solids control after one day 67
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Table 106 Technetium no solids control after four days 68
Table 107 Iodine no solids control after one day 68
Table 108 Iodine no solids control after four days 68
Table 109 Vault 2- plutonium after one day 69
Table 1010 Vault 2- plutonium after four days 69
Table 1011 Vault 2- neptunium after one day 70
Table 1012 Vault 2- neptunium after four days 70
Table 1013 Vault 2- technetium after one day 70
Table 1014 Vault 2- technetium after four days 71
Table 1015 Vault 2- iodine after one day 71
Table 1016 Vault 2- iodine after four days 71
Table 1017 TR545- plutonium after one day 72
Table 1018 TR545- plutonium after four days 72
Table 1019 TR545- neptunium after one day 73
Table 1020 TR545- neptunium after four days 73
Table 1021 TR545- technetium after one day 73
Table 1022 TR545- technetium after four days 74
Table 1023 TR545- iodine after one day 74
Table 1024 TR545- iodine after four days 74
Table 1025 TR547- plutonium after one day 75
Table 1026 TR547- plutonium after four days 75
Table 1027 TR547- neptunium after one day 76
Table 1028 TR547- neptunium after four days 76
Table 1029 TR547- technetium after one day 76
Table 1030 TR547- technetium after four days 77
Table 1031 TR547- iodine after one day 77
Table 1032 TR547- iodine after four days 77
Table 1033 Aged cement- plutonium after one day 78
Table 1034 Aged cement- plutonium after four days 78
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Table 1035 Aged cement- neptunium after one day 78
Table 1036 Aged cement- neptunium after four days 79
Table 1037 Aged cement- technetium after one day 79
Table 1038 Aged cement- technetium after four days 79
Table 1039 Aged cement- iodine after one day 80
Table 1040 Aged cement- iodine after four days 80
Table 1041 Plutonium sorbed to vial wall in no solids control 80
Table 1042 Neptunium sorbed to vial wall in no solids control 81
Table 1043 Technetium sorbed to vial wall in no solids control 81
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LIST OF FIGURES
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb 16
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb 17
Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb 18
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb 19
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples 25
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 25
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background 26
Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation 27
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation
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of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
SRNL-STI-2009-00636 Revision 0
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solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
SRNL-STI-2009-00636 Revision 0
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
SRNL-STI-2009-00636 Revision 0
30
As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
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31
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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34
seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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36
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
SRNL-STI-2009-00636 Revision 0
37
The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
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38
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
SRNL-STI-2009-00636 Revision 0
39
and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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40
under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
SRNL-STI-2009-00636 Revision 0
41
whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
SRNL-STI-2009-00636 Revision 0
42
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
43
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
44
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
45
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
46
60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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47
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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48
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
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49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
SRNL-STI-2009-00636 Revision 0
50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
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90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
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Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
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Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
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92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
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Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
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Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
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93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
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Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
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Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
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Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)
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Table 106 Technetium no solids control after four days 68
Table 107 Iodine no solids control after one day 68
Table 108 Iodine no solids control after four days 68
Table 109 Vault 2- plutonium after one day 69
Table 1010 Vault 2- plutonium after four days 69
Table 1011 Vault 2- neptunium after one day 70
Table 1012 Vault 2- neptunium after four days 70
Table 1013 Vault 2- technetium after one day 70
Table 1014 Vault 2- technetium after four days 71
Table 1015 Vault 2- iodine after one day 71
Table 1016 Vault 2- iodine after four days 71
Table 1017 TR545- plutonium after one day 72
Table 1018 TR545- plutonium after four days 72
Table 1019 TR545- neptunium after one day 73
Table 1020 TR545- neptunium after four days 73
Table 1021 TR545- technetium after one day 73
Table 1022 TR545- technetium after four days 74
Table 1023 TR545- iodine after one day 74
Table 1024 TR545- iodine after four days 74
Table 1025 TR547- plutonium after one day 75
Table 1026 TR547- plutonium after four days 75
Table 1027 TR547- neptunium after one day 76
Table 1028 TR547- neptunium after four days 76
Table 1029 TR547- technetium after one day 76
Table 1030 TR547- technetium after four days 77
Table 1031 TR547- iodine after one day 77
Table 1032 TR547- iodine after four days 77
Table 1033 Aged cement- plutonium after one day 78
Table 1034 Aged cement- plutonium after four days 78
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Table 1035 Aged cement- neptunium after one day 78
Table 1036 Aged cement- neptunium after four days 79
Table 1037 Aged cement- technetium after one day 79
Table 1038 Aged cement- technetium after four days 79
Table 1039 Aged cement- iodine after one day 80
Table 1040 Aged cement- iodine after four days 80
Table 1041 Plutonium sorbed to vial wall in no solids control 80
Table 1042 Neptunium sorbed to vial wall in no solids control 81
Table 1043 Technetium sorbed to vial wall in no solids control 81
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LIST OF FIGURES
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb 16
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb 17
Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb 18
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb 19
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples 25
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 25
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background 26
Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation 27
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation
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of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
SRNL-STI-2009-00636 Revision 0
24
solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
SRNL-STI-2009-00636 Revision 0
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
SRNL-STI-2009-00636 Revision 0
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
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As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
SRNL-STI-2009-00636 Revision 0
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Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
SRNL-STI-2009-00636 Revision 0
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
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37
The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
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38
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
SRNL-STI-2009-00636 Revision 0
39
and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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40
under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
SRNL-STI-2009-00636 Revision 0
41
whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
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42
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
43
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
44
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
45
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
46
60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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47
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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48
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
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49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
SRNL-STI-2009-00636 Revision 0
50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
SRNL-STI-2009-00636 Revision 0
51
90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
SRNL-STI-2009-00636 Revision 0
52
Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
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Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
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92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
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Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
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Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
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93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
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Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
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Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
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Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)
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Table 1035 Aged cement- neptunium after one day 78
Table 1036 Aged cement- neptunium after four days 79
Table 1037 Aged cement- technetium after one day 79
Table 1038 Aged cement- technetium after four days 79
Table 1039 Aged cement- iodine after one day 80
Table 1040 Aged cement- iodine after four days 80
Table 1041 Plutonium sorbed to vial wall in no solids control 80
Table 1042 Neptunium sorbed to vial wall in no solids control 81
Table 1043 Technetium sorbed to vial wall in no solids control 81
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LIST OF FIGURES
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb 16
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb 17
Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb 18
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb 19
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples 25
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 25
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background 26
Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation 27
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation
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of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
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solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
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As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
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Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
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37
The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
SRNL-STI-2009-00636 Revision 0
38
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
SRNL-STI-2009-00636 Revision 0
39
and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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40
under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
SRNL-STI-2009-00636 Revision 0
41
whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
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42
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
43
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
44
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
45
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
46
60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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47
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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48
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
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49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
SRNL-STI-2009-00636 Revision 0
50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
SRNL-STI-2009-00636 Revision 0
51
90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
SRNL-STI-2009-00636 Revision 0
52
Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
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53
Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
SRNL-STI-2009-00636 Revision 0
54
92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
SRNL-STI-2009-00636 Revision 0
55
Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
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Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
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93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
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Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
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Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
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Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)
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LIST OF FIGURES
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb 16
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb 17
Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb 18
Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb 19
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples 25
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 25
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background 26
Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation 27
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation
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xii
of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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xiii
equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
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solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
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As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
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Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
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The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
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Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
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and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
SRNL-STI-2009-00636 Revision 0
41
whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
SRNL-STI-2009-00636 Revision 0
42
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
43
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
44
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
45
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
SRNL-STI-2009-00636 Revision 0
46
60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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47
Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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48
Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
SRNL-STI-2009-00636 Revision 0
49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
SRNL-STI-2009-00636 Revision 0
50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
SRNL-STI-2009-00636 Revision 0
51
90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
SRNL-STI-2009-00636 Revision 0
52
Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
SRNL-STI-2009-00636 Revision 0
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Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
SRNL-STI-2009-00636 Revision 0
54
92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
SRNL-STI-2009-00636 Revision 0
55
Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
SRNL-STI-2009-00636 Revision 0
56
Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
SRNL-STI-2009-00636 Revision 0
57
93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
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Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
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Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
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Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)
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of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset 27
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb 28
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples 29
Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb (blueleft) and 1 ppb (redright)) datasets were prepared in triplicate and the error bars show the standard deviation 31
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 31
Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb (redleft) 5 ppb (greenmiddle) and 10 ppb (blueright) systems Therefore no error bars are present 32
Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation 33
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples 33
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background 34
Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day
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xiii
equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation 35
Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates 36
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets 36
Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates 38
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 39
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples 39
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation 40
Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions 42
Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions 43
Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions 44
Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions 45
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xiv
LIST OF ABBREVIATIONS
DDI water Distilled deionized water ICP-MS Inductively coupled plasma ndash mass spectrometer
Kd Distribution coefficient LSC liquid scintillation counting NOM Natural organic matter PA Performance Assessment ppb parts per billion ppq parts per quadrillion QAQC Quality AssuranceQuality Control SA Special Analyses SRNL Savannah River National Laboratory SRS Savannah River Site
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15
10 Introduction Performance Assessments (PA) are risk calculations designed to determine (1) the maximum
amount of radioactivity that can be safely buried in a subsurface facility and (2) the potential human risk associated with disposing of radioactive waste in a subsurface facility Special Analyses (SAs) are similar to PAs except that they are designed to address specific issues related to PAs such as a new discovery since the PA was issued Commonly parameters describing the extent that a radionuclide interacts with solids at the source vadose zone and aquifer influence the extent of calculated human risk The two parameters that the SRS use to represent radionuclidesolid interactions are Kd and apparent solubility values together these parameters are referred to as sorption values Sorption values vary with radionuclides groundwater chemistry and the type of solid phase (and for cementitious materials by the age of the material during the calculation) In this work Kd and apparent solubility values are reported for 99Tc 127I 237Np and 242Pu sorption to various cementitious formulations
20 Objectives
The objectives of this work were to 1 Determine the influence of cementitious formulation on technetium (Tc) iodine (I) neptunium
(Np) and plutonium (Pu) sorption under oxidizing conditions The specific formulations that were evaluated included 1) an aged cement recovered from a 30-year old outdoor concrete pad on the SRS 2) Vault 2 concrete 3) TR545 saltstone and 4) TR547 saltstone (additional details are presented in Section 30 Materials and Methods)
2 Measure Tc I Np and Pu sorption to the cementitious formulations under reducing conditions
30 Materials and Methods
31 Preparation of ICP-MS Standards Stock Solutions and Working Solutions
311 242Pu
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 434H) was used to prepare a stock 242Pu solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 parts per billion (ppb) standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 inductively coupled plasma ndash mass spectrometer (ICP-MS) for quantification of 242Pu A representative calibration curve for 242Pu is shown in Figure 31 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard quality assurancequality control QAQC protocols for the instrument (between 80 and 120)
A 242Pu stock solution was prepared by dissolving 1mg of Pu(NO3)4 obtained as a Certified Reference Material from New Brunswick Laboratory (CRM 130) This CRM is gt999 242Pu by atom percent The CRM was dissolved in 20mL of 8M HNO3 (Aristar Optima Grade) Because no chemicals or heat have been introduced to manipulate the Pu oxidation state it can be assumed that Pu(IV) is the predominant oxidation state in this stock solution A working solution to be used in spiking 242Pu experiments was prepared by diluting 25 mL of the CRM stock solution with 100 mL 10 M Aristar Optima HNO3 The concentration of 242Pu in this stock solution was determined using ICP-MS calibrated using the NIST SRM standards The concentration of Pu in this stock solution was 1065 ppb The total Pu
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concentration was also determined using liquid scintillation counting using the isotopic ratios reported for CRM 130 These compared favorably with the ICP-MS results but are reported here as a rigorous standardization because the isotopic ratios of CRM 130 have not yet been certified
Figure 31 Screen capture of a typical 242Pu calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999872 Intercept Conc (Detection Limit) = 0000044 ppb
312 237Np
A National Institute of Standards and Technology Standard Reference Material (NIST SRM 4341) was used to prepare a stock 237Np solution by dilution in 2 Aristar Optima HNO3 All volume additions were monitored gravimetrically This working solution was then used to make a set of 001 005 1 2 5 10 ppb standards by dilution using 2 HNO3 Again all volume additions were monitored gravimetrically These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 237Np A representative calibration curve for 237Np is shown in Figure 32 The instrument performance was monitored using 209Bi 232Th and 238U as internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
A compiled 237Np stock solution from the Environmental Engineering and Earth Science (EEampES) inventory (primarily purchased from Isotope Products Valencia CA) was evaporated to dryness then the residue was brought up in approximately 5mL 80 M HNO3 Then 10 M hydroxylamine hydrochloride (NH2OHHCl EMD Chemicals ACS grade) and water were added to achieve a 3M HNO303M NH2OHHCl solution This solution was purified by extraction chromatography using Eichrom TEVA resin packed in a Bio-Rad poly-prep column The 3M HNO303 M NH2OHHCl neptunium solution was loaded on a 2 mL column and washed with 3 column volumes of 3 M HNO3 The Np(IV) was eluted with 002 M HCl + 02 M HF The effluent was evaporated to dryness then redissolved in 10 M HNO3 Additional 10 M HNO3 was added to maintain a approximately 10 mL then the solution was evaporated to incipient dryness and redissolved in a 50 mL of 10 M HNO3 An aliquot of the stock solution was evaporated to dryness on a stainless steel planchet and counted on the EGampG Ortec Alpha Spectrometer (Octete PC Detectors) No other alpha energies besides 237Np were observed The approximate concentration was determined using liquid scintillation counting and little 233Pa was observed The fuming in HNO3 as performed at the end of the purification procedure will drive Np to the soluble pentavalent state This is the stable oxidation state of Np under the experimental conditions Therefore experiments performed here can be assumed to be initially Np(V) The exact Np
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concentration in this solution was determined using ICP-MS calibrated with a NIST standard as discussed in section 312 below
A 237Np working solution (Working Solution 1) was created by pipetting an aliquot of the 237Np stock solution into a 100 mL Nalgene Teflon bottle and diluting with 2 BDH Aristar Ultra HNO3 to give a working solution concentration of 820 ppb All volumes were monitored gravimetrically Analysis on the ICP-MS calibrated against NIST Standards as described below gave a concentration of 820 ppb in Working Solution 1
Figure 32 Screen capture of a typical 237Np calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999981 Intercept Conc (Detection Limit) = 0000026 ppb
313 99Tc
A 99Tc working solution was prepared by diluting a stock solution of 99Tc (from the EEampES inventory purchased from Isotope Products Valencia CA) in distilled-deionized water (DDI Resistivity gt18 MΩcm) The oxidation state of Tc was not measured However based on the aqueous concentration in the DDI water solution Tc(VII) is the expected oxidation state The reduced Tc(IV) oxidation state would not be soluble under these conditions The expected concentration of 950 ppb based on the dilution was verified using liquid scintillation counting The 99Tc working solution was used to make 001 005 1 2 5 and 10 ppb standards by dilution using 2 HNO3 These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 99Tc A screen shot of a representative calibration curve is shown in Figure 33 The instrument performance was monitored by interpolating between 89Y and 115In internal standards The recovery of each sample during analysis was corrected based on the internal standard recovery The internal standard recoveries remained within standard QAQC protocols for the instrument (between 80 and 120)
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Figure 33 Screen capture of a typical 99Tc calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999984 Intercept Conc (Detection Limit) = 0000013 ppb
314 127I
A 100 microgmL iodate (IO3-) stock solution from High Purity Standards (Charleston SC) was used
to make 1 5 10 50 and 100 ppb standards by dilution using the ldquotraprdquo solution (discussed in Section 32 below) These standards were used to calibrate the Thermo Scientific X Series 2 ICP-MS for quantification of 127I A screen shot of a representative calibration curve is shown in Figure 34 The use of a reducing basic trap solution for iodine analysis limits the number of available internal standards that can be used to monitor ICP-MS instrument performance during iodine analysis Experiments are underway to identify acceptable internal standards However the data presented in this work did not use any internal standards prior to rigorous testing and analysis of representative standards As with the analyses for all isotopes (Tc I Np and Pu) spiked QAQC samples were frequently analyzed throughout the analysis as a check on instrument performance While these values cannot be used to correct individual samples in the same manner that the internal standards can they can be used to ensure accurate measurements of each isotope In almost all cases QAQC standards were within 10 of the expected value Because the average internal standard recovery ranges between 80 and 120 for the ICP-MS the iodine QAQC standard appears to be acceptable However a significant amount of ongoing work is testing various internal standards to improve the accuracy of iodine analysis using ICP-MS In one experiment (discussed in detail below) the QAQC standards deviated by an average value of 195 This will be specifically discussed below
Because experiments were performed with 127I concentrations up to 1000 ppb the 100 microgmL (ppm) stock iodate solution from High Purity Standards was used as the working solution
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Figure 34 Screen capture of a typical 127I calibration curve using Thermo PlasmaLab software to control the data collection and analysis R2=0999991 Intercept Conc (Detection Limit) = 024 ppb
315 Cementitious Materials Selected for Experiments There were four cementitious materials selected for this sorption study The first referred to as Aged Cement is a 30 year old sample that does not contain any reducing slag The aggregate from the Vault 2 cement had its aggregate removed prior to conducted tests in an effort to make subsamples more uniform This was necessary because some of the aggregate were larger than the 05 g subsamples used in individual sorption tests The Vault 2 cementitious material contained 17 dry wt- reducing slag on a dry weight basis before the water was added to the mix (Table 31) The TR547 and TR545 saltstone formulations contain 45 dry wt- and 90 dry wt- reducing slag respectively
Table 31 Characteristics of saltstone formulations used in this work Kaplan et al (2008)
Sample Percent Reducing Slag (dry wt-) (c)
Percent Portland Cement
(dry wt-) (c)
Percent Fly Ash
(dry wt-) (c)
Percent Aggregatesand ( dry wt-) (c)
Reducing Equivalents
(microeqg)
Aged Cement 0 10 45 45 855 plusmn 101(a)
Vault 2 Cement 17 10 45 0 178(b)
TR547 45 10 45 0 607(b) TR545 90 10 0 0 681(b) Blast furnace slag 100 0 0 0 819(b) (a) Kaplan et al (2008) (b) Roberts and Kaplan (2009) (c) All percentages of saltstone formulations are reported on a dry weight percentage basis that is the weight of the ingredients before water was added (d) Based on Table 8 in Dixon et al (2008 SRNL-STI-2008-00421) which shows the following quantity (lbscu yd) for saltstone Vault 2 Mix 1 concrete formulation 201 cement (1271 wt-) 268 slag (1695 wt-) 447 silica fume (283 wt-) 1563 fly ash (989 wt-) 911 fine sand (5762 wt-) The large aggregate was removed before the sorption tests were conducted The large aggregate accounted for 75 wt- of the original field sample not the sample used in these test before water was added to the mix TR547 is referred to as the Baseline by Dixon et al (2008) and is described in more detail in Appendix C (Mix 2) by Dixon et al (2008) (Control-BFSPC) and 1 (Baseline)
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TR545 saltstone contains 90 reducing slag and it is Mix 1 in Dixon et al (2008) and is described as
ldquoA control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 Portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix compositionrdquo
32 ICP-MS Detection Limits
The PlasmaLab software platform determines a detection limit for each isotope based upon the intercept concentration A new calibration curve was generated for each experimental run and curves were very similar Using representative calibrations curves the detection limits for each isotope were as listed in Table 32 Note the higher detection limit for 127I is primarily due to the higher background count rate observed on the instrument This is believed to be due to the minimum purity levels of chemicals required for the iodine ldquotraprdquo solution as discussed in Section 33 below Therefore experiments were run with initial iodate concentrations higher than Tc Np and Pu to maintain analytical sensitivity
Table 32 Detection limits for each isotope based on representative calibration curves generated in PlasmaLab software associated with the ICP-MS
33 Experimental Methods
The experimental methods used in this work followed closely those previously described for experiments examining radionuclide sorption to saltstone (Kaplan et al 2007 Kaplan et al 2008) Brief descriptions of each method are provided below
Preparation of Calcite Solution Using a hotstirring plate 10 L of distilled-deionized (DDI)
water was heated to 3-100C above room temperature Then 001 g CaCO3 (EM Science ACS grade) was added to the solution and the resulting suspension was mixed for 24 hours at the elevated temperature The solution was then vacuum filtered through a 045-microm filter to ensure no solid CaCO3 remained in solution
Preparation of 2 HNO3 Analysis of Tc Np and Pu on the ICP-MS required dilution in 2
HNO3 This was prepared by adding 28 mL of Aristar Optima HNO3 from a clean graduated cylinder (designated to 2 HNO3) into a 1 L volumetric flask (designated to 2 HNO3) partially filled with DDI water and then further diluted to volume
Isotope Detection Limit 99Tc 0000013 ppb 127I 0244 ppb
237Np 0000026 ppb 242Pu 0000044 ppb
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Preparation of Trap Solution for Iodine Analysis Analysis of I required the use of a reducing
basic solution that was capable of reducing iodate to iodine and holding the iodine in solution This minimized the loss of I during sample analysis A 1 L trap solution was prepared by weighing out 00500 g NaHSO3 (Fisher Scientific ACS Grade) on a calibrated Sartorous LA 230S scale and adding it to a 1L volumetric flask Then 40 mL of 25 ww tetramethylammonium hydroxide (Alfa Aesar electronic grade) and 10 mL CFA-C solution (Spectrasol Inc) were added to the volumetric flask via a calibrated 1000-5000 microL Eppendorf Research pipette The solution was then diluted to volume with DDI water
34 Experimental Protocol for Sorption Experiments under Aerobic Conditions
Falcon BlueMax 15mL polypropylene vials were labeled and weighed to within 0001 g on a calibrated Sartorious LA 230S scale The scale was then zeroed and 025 +- 001 g of a given solid were added to each tube and the weight was recorded to within 0001g
For each of the four solids three sets of triplicate samples were prepared The three sets of samples were used to allow for experiments to be run with varying concentrations of each isotope Target initial concentrations for 99Tc 237Np and 242Pu samples were 1 ppb 5 ppb and 10 ppb Target initial concentrations for the 127I samples were 100 ppb 500 ppb and 1000 ppb A set of no solids controls at initial concentrations of 1 ppb and 10 ppb for 99Tc 237Np and 242Pu and initial concentrations of 100 ppb and 1000 ppb 127I were also prepared by adding the calcite solution to pre-weighed pre-labeled centrifuge tubes as discussed above
The solids were equilibrated with the calcite solution before spiking with the radionuclides This was done by adding 10 plusmn 01 mL of calcite solution to each tube and recording the mass The samples were then placed on a Thermo Scientific shaker overnight After 24 hours the solutions were allowed to settle for 1 hour The pH was then measured and the samples were then centrifuged for 15 minutes at 8000 rpm to further separate the solids The aqueous phase was then decanted and 10 plusmn 01 mL of calcite solution was added to each tube The weight of the tube (labeled tube + solid + calcite solution) was measured to within 0001g During this washing process the pH was monitored and held steady throughout the process The pH ranged from 11-12 depending on the particular saltstone used During the experiments the exact pH for all samples at all equilibration times was measured and is reported in Appendix A and B
The resulting suspensions were then spiked with 127I 237Np 242Pu and 99Tc It is important to note that all four isotopes were added to the same vial Use of the ICP-MS to determine the concentration of each isotope allows for a single solution to contain all analytes of concern This allowed for a greater variability in the sample set and increased replicates as opposed to running individual sorption tests for each isotope For the systems with initial 99Tc 237Np and 242Pu concentrations of 10 ppb and initial 127I concentration of 100 ppb a 100 microL aliquot of each radionuclide working solution was added to the first three tubes for each solid The addition was made with the tube resting on a tared analytical balance so that the exact mass of each radionuclide solution added was recorded and the solution was gently swirled before the next radionuclide was added The 5 ppb 237Np 242Pu and 99Tc and 500 ppb 127I samples were prepared in the same manner but adding 50 microL of the respective spike solutions The final three tubes with initial 237Np 242Pu and 99Tc concentrations of 1 ppb and 100 ppb 127I were prepared by using 10 microL of the spike solutions for all four solids as well as a set of solid-free controls (No-Solids Controls) For clarity this experimental matrix is shown in Table 33 below
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Table 33 Experimental Matrix of Sorption Experiments under Aerobic Conditions
Experiment Initial Concentration 99Tc 237Np 242Pu Initial Concentration 127I
Solids-Present 1 ppb 100 ppb Solids-Present 5 ppb 500 ppb Solids-Present 10 ppb 1000 ppb
Solids-Free 1 ppb 100 ppb Solids-Free 10 ppb 1000 ppb
After spiking the radionuclides a precalculated amount of 10M NaOH was added to each sample
to counter the acidic radionuclide spike solutions and the pH of one of the triplicate samples was measured to ensure the proper pH range was reached The samples were then placed on and end-over-end shaker to mix at approximately 8 rpm After 24 hours the samples were removed from the shaker and the pH of each sample was measured using an Orion Ross semi-micro glass electrode calibrated against pH 4 7 and 10 buffers (Thermo) The samples were then shaken and a transfer pipette was used to transfer 35 mL of a homogenous suspension to a 5mL syringe The solution was then passed through a 100 nm nylon syringe filter The first 025-050 mL of filtrate was discarded and the remaining filtrate was collected in a clean polyethylene vial Then 10 mL of the filtrate was removed and diluted in 90 mL 2 HNO3 The mass of each phase was determined and recorded gravimetrically Then 10 mL of the remaining filtrate was transferred to a clean Falcon BlueMax 15mL vial and diluted with 90 mL of trap solution for 127I analysis Again the volume of each phase was monitored gravimetrically After the 24 hour sampling event the samples were put back on the shaker to mix for three additional days On day four the above sampling procedure was repeated
The 237Np 242Pu and 99Tc samples can be run on the Thermo Scientific ICP-MS using the standard setup and procedure which included a standard flow glass nebulizer and bulb spray chamber However for the 127I analysis the ICP-MS must be reconfigured to accommodate the basic reducing trap solution This is to alleviate problems with iodine signal stability over time frequently observed in ICP-MS analysis The reconfigured instrument uses an Elemental Science Microflow PFA-100 Teflon nebulizer with a flow rate of 100microLmin along with a sapphire torch and a Teflon spray chamber This configuration must be run with a low pump speed to prevent back pressure on the system Two 30 minute stability tests were performed using a 50 ppb iodate solution Each experiment consisted of 40 separate measurements After each experiment was completed the uncorrected mass counts were examined and found to stay steady over the sampling period The relative standard deviation ( RSD) over all samples for each experiment was 1866 and 1460 respectively This shows that there was no significant ldquomemoryrdquo or loss of the iodine signal over time and that the reconfigured instrument has a stable iodine signal over time However as will be discussed below some difficulty has been encountered in finding an adequate internal standard for iodine analysis
35 Experimental Protocol for Sorption Experiments under Anerobic Conditions In order to examine the effects of reducing conditions of sorption of each isotope to the various cementitious samples a series of sorption experiments were performed in an anaerobic glovebox under a 2 H2(g) 98 N2(g) atmosphere Based on the measured pH and EH of these systems as discussed below these systems were at the point of reducing water Therefore they are expected to represent a lower end of the possible range for reducing conditions expected in the porewater available within cementitious materials
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Preparation of Calcite for Reducing Conditions Approximately 35 L of DDI water was boiled for 45 minutes Argon was slowly bubbled through the water as it cooled Once it cooled to below 500C approximately 3 g of calcite was added This solution mixed overnight under a continuous Ar flow After 12 hours the solution was moved into an oxygen free glove bag for filtration as described in 3231 After filtration the calcite solution was moved into the glove box
Preparation of Working Solutions under Reducing Conditions The calcite and solid solutions
were prepared in the glove box using the previously mentioned procedure used under aerobic conditions The radionuclide working solutions were transferred to the glovebox and stirred open to the reducing atmosphere for at least three days The concentration of each isotope in the working solutions was measured to determine any change in the concentration due to evaporation while the solutions were equilibrating
The preparation and spiking of samples for sorption experiments was performed exactly as described for the oxidizing conditions except all sample handling was performed in the glovebox After the 1 day and 4 day equilibration the samples were filtered within the glovebox then transferred outside for dilution and ICP-MS analysis similar to the description provided about for the oxidizing conditions For these experiments only 4 mL of either 2 HNO3 or trap solution were used to dilute the filtrate instead of the 90 mL used above for experiments performed under oxidizing conditions
36 Examination of Sorption to Vial Walls for Solids and No Solids Controls
As will be discussed below the solid-free controls samples indicated significant loss of Np and Pu Once the one and four days samples were collected and run on the ICP-MS it was necessary to determine the degree each radionuclide was sorbing to the vial walls The remaining suspensions and controls were emptied into a waste container Then 5 mL of the calcite solution was added to each vial using a calibrated pipette The vials were sonicated for approximately one minute and then emptied into the waste container Another 5 mL of calcite solution was added for the second wash and then discarded into the waste container This procedure was expected to remove any soluble Pu from the system or Pu associated with colloidal particles After each vial was washed 10 mL of 2 HNO3 was added using a calibrated pipette The acid solution is expected to remove any Tc Np or Pu associated with the vial walls This procedure has been shown to complete mass balances of Pu in similar sorption experiments using Pu (Powell et al 2002) This process was performed for both the solid suspension and the no solids controls The samples were then run on the ICP-MS to determine the concentration of 99Tc 237Np and 242Pu sorbed to the vial walls
37 Data Analysis The solubilities of 242Pu and 237Np were calculated by using the formula
nuclide
nuclide
nuclideMSICP
sol Mg
gCC
)(10 6
microminus
minus
= (Equation 31)
Csol = observed nuclide solubility (molnuclidekgsolution) CICP-MS = aqueous concentration of nuclide from ICP-MS measurement (ppb micrognuclidekgsolution) Mnuclide = molecular mass of nuclide (gnuclidemolnuclide)
In order to determine the Kd values one first needs to determine the concentration on the solid by using
SRNL-STI-2009-00636 Revision 0
24
solid
calcitespikeaqspikecalcite
spikestock
solid m
mmCmmmC
C)(
)()(
+⎥⎥⎦
⎤
⎢⎢⎣
⎡minus
+
lowast
= (Equation 32)
Csolid = calculated solid phase concentration of the nuclide (ppb) Cstock = concentration of the nuclide stock solution (ppb) mspike = mass of nuclide spiked into the saltstone suspension (g) mcalcite = total mass of calcite solution used in the saltstone suspension (g) Caq = aqueous concentration of nuclide from ICP-MS measurement (ppb) msolid = mass of the saltstone used in the suspension (g)
The Kd can be calculated using the equation
aq
solidd C
CK = (Equation 33)
Kd = solid-water partitioning coefficient (gsolutiongsolid assuming density of 10 gmL traditional
unit of mLsolutiongsolid can be obtained) This Kd Equation (33) is numerically equivalent to the traditional Kd equation proposed in ASTM D-4646 which has been used in previous saltstone experiments (Kaplan et al 2007 Kaplan et al 2008)
40 Results and Discussion
41 Radionuclide Sorption to Cementitious Formulations under Oxidizing Conditions
Figure 41 shows Pu Kd values ranging from 104 to gt105 mLg Generally for each solid the Kd increases with increasing initial Pu concentrations typical behavior of systems where the aqueous concentrations of the radionuclides are solubility controlled This is not expected because the Kd expression indicates that the Kd value should remain constant with increasing total Pu concentrations It was noted that aqueous phase concentration of Pu remained relatively constant in all samples (see discussion below regarding Pu solubility) Therefore the sorption capacity of each solid phase for Pu has not been overcome For each of these solid phases it appears the solutions had reached equilibrium before the first samples were taken at 24 hours In each case the Kd values for the one day and four day are similar A trend between the solid phases is not discernible The aged cement with no reducing slag was expected to have the lowest Kd values but in actuality it has the highest Kd Also there is no correlation with the concentration of reducing slag The Vault 2 samples with 17 dry wt- reducing slag has a Kd similar to that of the TR547 (45 dry wt- slag) while the saltstone with the most slag TR545 (90 dry wt- slag) has the lowest Kd value Others have observed that Pu Kd values of cementitious materials are similar in the absence and presence of slag (Allard et al 1984 Hoaglund et al 1985)
It was observed that similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 42 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 42 is an average of nine measurements Using the highest reported value with the expected maximum error (0018 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the
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saltstone formulations will be approximately 7 x 10-11 molL as calculated using Equation 31 This is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001)
Figure 41 Plutonium Kd Values under Oxidizing Conditions Plutonium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation of samples except as follows value for dataset TR547-4d 10 ppb is reported based on duplicate samples
Figure 42 Plutonium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
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Overall the Kd values for Np range from 105 to gt106 with only a few outliers The most significant outlier is the 1 ppb solution in the TR545 sample after the four-day equilibration It drops two orders of magnitude while the 5 and 10 ppb solutions remain constant However this result is most likely an analytical artifact from working at the detection limits of the ICP-MS In the one-day equilibration samples only one of the triplicates S-2-E had detectable Np while in the four-day equilibration samples only S-2-F had detectable amounts present The graph also shows that with the exception of the 5 ppb sample in the aged cement Np sorption to TR545 (90 dry-wt- slag) and TR547 (45 dry wt- slag) have Kd values approximately one order of magnitude over the aged cement (no slag) and Vault 2 (17 dry wt- slag) samples
It was observed that similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 44 shows the average aqueous phase concentrations measured after one day and four-day equilibrations for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 44 is an average of nine measurements of Np concentration unless stated otherwise Using the highest reported value with the expected maximum error (00026 ppb for solid TR545) the maximum expected aqueous concentration of Pu in the pore water associated with the saltstone formulations will be approximately 2 x 10-11 molL
Figure 43 Neptunium Kd values under oxidizing conditions Neptunium Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total plutonium concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and error bars represent standard deviation of samples except as follows value for datasets TR545-1d 1ppb TR545-4d 1 ppb TR547 4d 1 ppb TR545-4d 10 ppb TR547-1d 1ppb TR547-4d 10 ppb are reported based on a single sample and for dataset TR545-1d 5ppb is reported based on duplicate samples Kd values limited to gt106 were at instrumental background
The Kd values for Tc are significantly lower than that of Pu or Np As a whole the values are
comparable The values for the one-day and four-day equilibrations solutions in the Vault 2 (17 dry wt- slag) and TR545 (90 dry wt- slag) remained constant within reasonable error with just a slight increase from the one-day to four-day equilibration However the Aged Cement (no slag) and TR547 (45 dry wt- slag) showed a noticeable decrease from day one to day four (Figure 45)
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Figure 44 Average solubility of Np under oxidizing conditions Neptunium solubility for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility except as follows TR545-1d is based on 6 samples TR545- 4d on 5 samples TR547-1d on 7 samples and TR547- 4d on 5 samples The error bars represent standard deviation
Figure 45 Technetium Kd values under oxidizing conditions Tc Kd values for various saltstone formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows data sets for Vault 2-1d 1ppb were duplicates and TR547- 4d 10 ppb is based on a single dataset
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Similar to the Tc Kd values the 127I Kd values are much lower than those of Pu and Np The amount of reducing slag present in each of the solids does not appear to have a drastic effect on the 127I Kd values In fact the initial (one day) Aged Cement (0 slag) samples had a Kd almost two orders of magnitude above those with reducing slag The cause of this behavior is not known but it has been shown that iodate IO3
- the oxidized form of iodine sorbs more strongly than iodide I- to charged surfaces (Schwehr et al 2009 Yoshida et al 1992 Fukui et al 1996) It is possible that the slag is reducing the iodine to the I- form converting it to a species that is less likely to sorb to saltstone Additional work would be required to confirm the oxidation state of iodine when associated with saltstone
Figure 46 Iodine Kd Values under Oxidizing Conditions Iodine Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions Total iodine concentrations in the systems were 100ppb 500 ppb and 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent standard deviation of samples except as follows duplicates were used for dataset TR545- 1d 100ppb
42 Radionuclide Sorption to Vial Walls Under Oxidizing Conditions
Figure 47 shows the aqueous fractions found in the no-solids controls It provides a measure of the solubility of each radionuclide as well as examines the fraction of each radionuclide sorbed to the vial walls After one day only 25 of the Pu remained in solution and the concentration decreased even more after four days The loss of Pu from the aqueous phase may be due to sorption of Pu to the vial walls or precipitation of a Pu hydrous oxide solid (discussed with respect to Figure 49 below) Additional experiments would be required to examine the solubility of the Pu in high pH calcite saturated solutions
After one day about 80 of the Np remained in solution However the aqueous concentration in the initially 1-ppb solution was significantly reduced after four days Approximately 60 of the Np remained soluble in the initially 10-ppb solution Once again this drop could be due to sorption to the vial wall The Tc present after one day ranged from about 88 to about 95 and was virtually 100 after four days These values are consistent with internal standards used to monitor Tc detection performance on the ICP-MS Greater than 50 of the I remained in solution after the one-day and four-day equilibrations As shown in Figure 48 the standard deviation between the triplicate I control samples was
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quite large Additional control samples are required to understand the mechanism by which I is being lost from the aqueous phase in these samples
Figure 47 Plutonium Neptunium and Technetium Aqueous Fractions Fraction of Pu Np and Tc remaining in the aqueous phase for the No Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration for each radionuclide 10 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
Figure 48 Iodine Aqueous Fraction Iodine aqueous fraction for the no-solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under oxidizing conditions The total concentration of iodine was 1000 ppb as noted above Samples were prepared in triplicate and the error bars represent the standard deviation of the samples
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As discussed above the loss of Np and Pu from the no-solids control (Figure 47) could be due to
precipitation of Np and Pu hydrous oxides or sorption to the vial walls To quantify the differences between these possible sinks the vials were washed as described in Section 36 The data in Figure 49 indicate that significant sorption of Np and Pu to the vial walls may occur When combining the mass of Np represented in Figure 47 and Figure 49 there is almost 100 mass recovery of the Np sorbed to the vial wall and the aqueous fraction measured Therefore no precipitation of Np is expected However because 100 recovery was not achieved for Pu a Pu hydrous oxide phase could be precipitating which was washed out of the vial during the cleaning procedure The data in Figure 47 represent the no-solids control samples where there was no solid phase present for Np or Pu to sorb to besides the vial walls However when a cementitious solid phase is present in the sample there will be competition between the vial walls and the cement for sorption of Np and Pu Based on the affinity of metals for metal oxide surfaces as opposed to the polypropylene surface and the much higher surface site density expected for the cementitious samples it is assumed that the cementitious samples will out-compete the vial walls for sorption sites This thesis was tested by taking one of the triplicate samples from each sorption experiment with a solid phase present removing the solid phase from the tubes and leaching any sorbed Np and Pu from the tubes with acid as described in Section 36 Figure 410 and Figure 411 show that although some of the Pu and Np sorbed to the vial walls of the samples this amount accounted for less than 2 in all samples Therefore sorption of Np and Pu to the vial walls does not appear to be a significant factor in experiments where the solid phase is present Note these results do not discount the possibility that Pu hydrous oxide precipitates were forming in both the no-solid control experiments and experiments with cement formulations present Based on the observation of a constant aqueous phase concentration of Pu regardless of the initial Pu concentration the presence of a solubility limiting Pu phase cannot be discounted based on these data Further experiments examining the solubility of Pu in high pH calcite saturated solutions are required
Like Pu Np shows little affinity for the vial walls in the presence of a solid phase In each case tested there was significantly less than 1 of the total Np sorbed to the vial walls This behavior is consistent with the ~100 mass balance on Np achieve in the solid-free controls The majority of Np remained soluble in the solid-free control experiments Therefore it is expected that sorption of Np to the vial walls was the primary reason for the loss of Np from the aqueous phase in the no-solids systems rather than precipitation of a Np solid phase similar to the process discussed for Pu above This assumption is based on the relative solubility of Np(V) as compared with Pu(IV)
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Figure 49 Percent Pu and Np sorbed to vial walls of the no solids controls after the aqueous phases were discarded and the vials were washed Both the 10 ppb and 1 ppb datasets were prepared in triplicate and the error bars show the standard deviation
Figure 410 Percent Pu sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
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Figure 411 Percent Np sorbed to vial walls after the solids and aqueous phases were removed and the vials were washed The graph illustrates one sample from each of the 1 ppb 5 ppb and 10 ppb systems Therefore no error bars are present
43 Radionuclide Sorption to Cementitious Formulations under Reducing Conditions
Similar to the Pu Kd values under oxidizing conditions Pu Kd values ranged from 104 to gt105 under reducing conditions (Figure 412) Also similar to the results under oxidizing conditions the Kd increases with increasing initial Pu concentration Again this behavior is indicative of the aqueous phase concentration of Pu being controlled by solubility of Pu rather than by sorption In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values after one day and four days are very similar Also it appears that the amount of reducing slag does not make a significant difference in the Kd value In fact the TR547 solid consists of 45 reducing grout but produces approximately the same Kd values of the aged cement which does not have any reducing grout Each of these Kd values are higher than the TR545 which is 90 reducing grout These findings are in agreement with those conducted by Allard et al (1984) and Hoglund et al (1985) who reported that concrete containing reducing agents (slag similar to that used in our study) did not have greater Pu Kd values than those that did not contain slag
Similar aqueous concentrations of Pu were observed regardless of the solid phase present Figure 36 shows the average aqueous phase concentrations measured after one day and four days for all solids As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 412 is an average of up to nine measurements of the Pu aqueous concentrations Using the highest reported value with the expected maximum error (00045 ppb for solid Vault 2) the maximum expected aqueous concentration of Pu in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL (calculated from Equation 31) This value is on the same order as the solubility of Pu hydrous oxide solid phases (Neck and Kim 2001) A best value would be 10-12 molL
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Figure 412 Pu Kd Values under Reducing Conditions Plutonium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and error bars represent standard deviation
Figure 413 Average Solubility of Plutonium under Reducing Conditions Plutonium solubility for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb as noted Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation of samples
The Np Kd values reported in Figure 414 obtained under reducing conditions are very similar to
those obtained under oxidizing conditions In each case the samples appeared to reach steady state within 24 hours This equilibration is evident because the Kd values between the one-day and fourndashday equilibrations are similar As was the case with Pu the amount of slag present in each solid does not
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seem to have a significant effect on the Kd values Again the aged cement with no slag has as high a Kd as the TR545 with 90 reducing slag
Similar aqueous concentrations of Np were observed regardless of the solid phase present Figure 314 shows the average aqueous phase concentrations measured after one day and four days for all solids All Kd values were gt 105 mLg which is considerably larger than those reported by Kaplan and Coates (2007) who reported Np Kd values to 1300 to 1600 mLg This difference can be attributed to two important experimental differences 1) the experiment was designed to permit larger Kd values to be measured (eg solid to liquid ratios and spike concentrations) and more importantly 2) a more sensitive analytical method ICP-MS was used instead of conventional low-energy gamma spectroscopy or liquid scintillation counting (LSC) analysis As stated above triplicate samples were prepared for each solid phase and each initial concentration Therefore each of the reported solubility values in Figure 415 is an average of up to nine measurements Using the highest reported value (to provide the most conservative most soluble values) with the expected maximum error (00045 ppb for solid TR545) the maximum expected aqueous concentration of Np in the pore water associated with the cementitious formulations will be approximately 2 x 10-11 molL A best value taking into consideration the less-than values which are depicted in Figure 414 as running off the top of the plot would be 10-12 molL
Figure 414 Np Kd Values under Reducing Conditions Neptunium Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Np concentrations in each system were 1 ppb 5 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent standard deviation Kd values limited to gt106 were at instrumental background
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Figure 415 Average Solubility of Neptunium under Reducing Conditions Neptunium solubility for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total plutonium concentrations in each system were 1ppb 5 ppb and 10 ppb Samples prepared in triplicate and an average of all samples (9) was used to determine average solubility The error bars represent standard deviation
A plot of the Tc Kd values for each cementitious formulations under reducing conditions is shown
in Figure 416 (log y-axis) and Figure 417 (reduced scale linear y-axis) The Kd values for each of the initial Tc concentrations are relatively similar This behavior is consistent with the Kd expression However the increasing Kd values from the one-day to four-day day equilibrations for each solid indicate that steady state was not reached within one day and it is unclear whether steady state was reached after four days A possible explanation for this behavior is that Tc(VII) was being reduced to Tc(IV) in these systems due to the reducing conditions As Tc(VII) was reduced the Kd would increase based on the high affinity of Tc(IV) for solid phases This proposed mechanism was observed by Lukens et al (2005) using an SRS saltstone material similar but not identical to TR547 Using synchrotron X-ray absorption fine structure spectroscopy they observed over a 453 month period that Tc(VII) incorporated into SRS saltstone slowly converted to Tc(IV) and that the nearest neighbor was initially predominantly oxygen and eventually became predominantly sulfur (described as a Tc(IV) phase TcSx) Lacking in Lukens et al (2005) is quantification of the solubility of Tc This analysis still needs to be completed along with re-oxidation studies (ie what is the rate that reduced Tc reoxidizes under ambient natural saltstone conditions)
Unlike Np and Pu Tc Kd values changed with the amount of slag included in the formulation Tc Kd values noticeable increase as the amount of slag in the formulation increased TR547 (45 dry-wt- slag) Kd value is visibly higher than the Aged Cement and Vault 2 Kd values while the most reducing TR545 (90 dry wt- slag) Kd value is significantly higher than the others Following a similar trend the reduction capacity that is the total quantity of reductant in the saltstone on a mass basis (units of milli-equivalents of charge per g) of TR547 had slightly greater or equal reduction capacity to that of TR545 (Roberts and Kaplan 2009)
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Figure 416 Tc Kd Values under Reducing Conditions Tc Kd values for various cementitious formulations measured after one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions Total Tc concentrations in each system were 1 ppb 5 ppb and 10 ppb Sample prepared in triplicate and error bars represent standard deviation except as follows TR547-1d 1 ppb is based on a single dataset and datasets Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicates
Figure 417 Data from Figure 416 replotted on a reduced linear scale for easier viewing Each sample was prepared in triplicate except as follows TR547-1d 1 ppb is based on a single dataset Vault 2-1d 5 ppb Vault 2- 4d 1 ppb Aged Cement-1d 5 ppb and Aged Cement-4d 1 ppb are duplicate datasets
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The calculated Kd values for I sorption to cementitious samples under reducing conditions are shown in Figure 418 Before discussing the data it should be noted that spiked QAQC samples which were analyzed on the ICP-MS along with the samples used to generate the data in Figure 418 were off by an average of 195 with one outlier of approximately 40 This dataset did not include the use of internal standards as discussed in Section 31 above1 Due to a lack of an internal standard the iodine results presented in this report should be considered with a minimum error estimate of 20
The iodine Kd values under reducing conditions are different from those observed under oxidizing conditions Under oxidizing conditions it appears they are at a steady state by day one However under reducing conditions there is a noticeable difference between days one and four indicating steady state was not reached by day one and possibly not by day four Another interesting observation is that the Kd values are decreasing from day one to four A possible reason for this behavior may be due to redox chemistry of iodine in this system If iodine partially or entirely exists in the form as iodate (IO3
-) it is possible it could be reduced to iodide I- within the reducing cementitious system These two iodine species sorb differently iodate sorbing to minerals more strongly than iodide (Denham et al 2009 Schwehr et al 2009 Fukui et al 1996 Yoshida et al 1992) It is hypothesized that the reducing environment of the saltstone is sufficient to reduce iodate ions to the more weakly binding form of iodine iodide
This is one of the few datasets (along with Tc) in this study where there may be a difference between the various solids The degree of iodate reduction would be expected to increase as the slag content increases As mentioned above reduction of iodate to iodide should result in a decrease in sorption Therefore higher Kd values should be observed for solids with less slag such as the Aged Cement (0 dry wt- slag) and Vault 2 (17 dry wt- slag) This is generally the case in Figure 418 where the highest Kd values are reported for the Aged Cement and the lowest values are for solid TR547 However this trend does not hold completely where the saltstone sample containing 90 slag (TR545) has generally equal or higher Kd values than the saltstone containing 45 dry wt- slag (TR547)
1 Clemson University is presently investigating appropriate internal standards for iodine analyses for ICP-MS Of those tested rhenium and molybdenum have shown some promise
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Figure 418 Iodine Kd Values under Reducing Conditions I Kd Values for various cementitious formulations measured after one day equilibration (1d) and four day equilibration (4d) under reducing conditions Total iodine concentrations in each system were 100 ppb 500 ppb and 1000 ppb as noted Sample prepared in triplicate and error bars represent standard deviation of samples except as follows Vault 2-4 d 100 ppb is a single dataset while the datasets for Vault 2-1 d 100 ppb 4 d 1000 ppb TR545-4 d 1000 ppb 100 ppb TR547-4 d 1000 ppb 500 ppb 100 ppb and Aged Cement- 4 d 1000 ppb and 100 ppb are all based on duplicates
44 Radionuclide Sorption to Vial Walls under Reducing Conditions
The aqueous concentrations for Pu Np and Tc in the no solids controls are shown in Figure 419 The results are similar to those presented for experiments performed under oxidizing conditions above The 1 ppb Pu aqueous fraction is approximately three times greater than the 10 ppb fraction at day one This fraction decreases over time and by day four they are approximately equal when taking error into account This behavior is similar to the aqueous fraction under oxidizing conditions The 1 ppb Np aqueous fraction is significantly higher on both day one and day four than the aqueous fraction of the 10 ppb samples However each remained constant from day one to day four The 10 ppb aqueous fraction is twice as low as under oxidizing conditions which suggests either higher sorption to the vial walls or more precipitating out under the reducing conditions Like Pu and Np Tc shows a decrease from day one to day four especially for the 1 ppb samples The decrease in the 10 ppb sample is minimal and the aqueous fraction remains around 09 This value is slightly lower than that under oxidizing conditions
To examine the degree of sorption to the vial walls the tubes were washed again as performed for the experiments under oxidizing conditions above and similar results were found Ninety percent of the 1 ppb Pu sample was sorbed to the vial wall upon completion of the experiment which gives a 100 mass recovery when comparing this value to that found in Figure 419 However this result is not the case with the 10 ppb samples where approximately 75 of the mass remains unaccounted It is noteworthy that approximately 25 of the Pu from the 10 ppb solution sorbed to the vial walls under both oxidizing
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and reducing conditions Np follows the same trend as Pu while less than 005 of the Tc sorbed to the wall
Figure 419 Plutonium Neptunium and Technetium No-Solids Aqueous Fractions under Reducing Conditions Pu Np and Tc aqueous fractions of No Solids controls after a one-day equilibration (1d) and four-day equilibration (4 d) under reducing conditions Total concentration for each radionuclide was 1 ppb and 10 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
Figure 420 Percent of Pu Np and Tc sorbed to the vial walls of the No Solids control samples under reducing conditions Each the 1 ppb and 10 ppb samples were prepared in triplicate and the error bars represent the standard deviations of triplicate samples
Under reducing conditions the fraction of I remaining in the aqueous phase was around 90 with
almost 100 mass recovery of the 100 ppb I after the four-day equilibration These graphs show that
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under reducing conditions there will only be a small fraction of I sorbing to the vial wall or coming out of solution This result is a much better mass recovery than under oxidizing conditions (Figure 48) which had a mass recovery of approximately 65 after four days This result is also consistent with the interpretation that there may be a iodine speciation change between the two redox treatments
Figure 421 Iodine No-Solids Aqueous Fractions under Reducing Conditions I aqueous fractions of No-Solids controls after a one-day equilibration (1d) and four-day equilibration (4d) under reducing conditions The total concentration for each system was 100 ppb and 1000 ppb Samples were prepared in triplicate and the error bars represent the standard deviation
50 Comparison of Radionuclide Sorption under Oxidizing and Reducing Conditions
In the following figures (Figure 51 through Figure 54) the data shown above has been replotted to allow comparison between the oxidizing and reducing conditions for each cementitious formulation General observations based on these data follow Vault 2 Observations (Figure 51)
bull Pu Kds are greater than 104 under both oxidizing and reducing conditions and Pu Kds are slightly lower under reducing conditions This could possibly be due to reduction of Pu(IV) to Pu(III) However no oxidation state analysis was performed in this work
bull Np Kds are generally greater than 104 under both oxidizing and reducing conditions Interestingly Np Kds are higher under reducing conditions by almost an order of magnitude This could possibly be due to reduction of Np(V) to Np(IV) However no oxidation state analysis was performed in this work
bull Regardless of the initial Np or Pu concentration similar aqueous phase concentrations of Np or Pu were observed in all samples This trend indicates that ldquosorptionrdquo of Np and Pu in these systems may be a combination of adsorption absorption and (co)precipitation processes
bull Tc appears to reach a steady state within four days under oxidizing conditions This behavior does not appear to be the case under reducing conditions After four days similar Kd values are reached under both oxidizing and reducing conditions It is unclear
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whether the Kd value of Tc will continue to increase under reducing conditions consistent with reduction of Tc(VII) to Tc(IV) The similarity in Kd values under both oxidizing and reducing conditions is an interesting observation and certainly warrants additional studies
bull I Kd values are similar under both oxidizing and reducing conditions However reducing condition systems may not be at steady state after four days while systems under oxidizing conditions appeared to reach a steady state The difference in rates may be due to reduction of iodate to iodine
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
TR545 and TR547 Observations (Figure 52 and Figure 53) bull Similar to the discussion above with respect to Vault 2 Pu Np and Tc all appear to reach
a steady state under oxidizing conditions and approach steady state slower under reducing conditions
bull Np and Pu Kd values are greater than 104 for all systems and time steps The aqueous phase concentrations of Np and Pu appear to be better described as a solubility in terms of the aqueous phase concentration of Np and Pu Similar aqueous phase concentrations of both Np and Pu were reached The data indicate that the initial Np and Pu concentration generally does not affect the aqueous phase concentration at an apparent steady state The presence of each solid phase appears to limit the aqueous phase concentration of both Np and Pu on the order of 10-11 molL
bull Tc shows significantly higher Kd values under reducing conditions versus oxidizing conditions
bull For all isotopes examined the sorption behavior to each of the solid phases is very similar
Aged Cement Observations (Figure 54) bull Pu appears to be close to steady state for each solid by day one with similar Kd values
reached on between day one and day four bull Np has a higher Kd under reducing conditions than oxidizing (105 under oxidizing
conditions and gt105 under reducing conditions) bull Neither set of Tc data was at steady state by day one and rates of sorptiondesorption
reactions appear to be different Tc Kds decrease from day one to four under oxidizing conditions but increase under reducing conditions
bull The Kd values for I under oxidizing conditions were considerably higher than those measured for I with any other solid Similar Kd values obtained for the same solids under reducing conditions indicate that the reported Kd values under oxidizing conditions appear to be suspect However analysis of the raw data gives no indication of an experimental artifact As discussed above these observations may be explained based upon the amount of slag contained within the solids which will affect the reducing capacity (ie No reducing slag is in the aged cement which could be reason the reduction of iodate to iodide (speculated in other samples) is not evident)
bull The difference in sorption behavior of iodine to the aged cement between oxidizing and reducing conditions also indicates that the reducing conditions of the solution may affect I redox behavior in addition to any reactivity expected in the solid phases
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Figure 51 Comparison of Tc I Np and Pu sorption to Vault 2 solid under oxidizing and reducing conditions
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Figure 52 Comparison of Tc I Np and Pu sorption to TR 545 solid under oxidizing and reducing conditions
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Figure 53 Comparison of Tc I Np and Pu sorption to TR547 solid under oxidizing and reducing conditions
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Figure 54 Comparison of Tc I Np and Pu sorption to Aged Cement under oxidizing and reducing conditions
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60 Comparison of Radionuclide Sorption and Solubility under Oxidizing and Reducing Conditions
To further summarize the data the following tables provide either the average solubility
(for Np and Pu) or average Kd (for Tc and I) determined under both oxidizing and reducing conditions for each cementitious formulation Each table lists the average value standard deviation and the number of replicate samples used to calculate the reported values
The solubility of Pu in the presence of each solid under oxidizing and reducing conditions is shown in Table 61 (this is taken from experiments equilibrated for four days not one day) Under oxidizing conditions the apparent solubility values associated with the Aged Cement (0 dry wt- slag) Vault 2 (17 dry wt- slag) and TR547 (45 dry wt- slag) are all similar with only a slight increase in solubility as the amount of reducing slag increases There is a significant increase of almost an order of magnitude for the most reducing saltstone TR545 (90 dry wt- slag) However these samples also have a standard deviation on the same order of magnitude as the solubility itself which when taken into account brings the solubility back into the range of the others Under reducing conditions the apparent solubility values are slightly lower than under oxidizing conditions In this set of samples the Vault 2 saltstone with 10 dry wt- reducing slag had the highest apparent solubility but once again when considering the standard deviation the values are similar
Table 61 Comparison of plutonium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 208E-12 565E-13
9 171E-12 661E-13
9
Vault 2 335E-12 671E-13 9 960E-12 808E-12 9 TR545 312E-11 414E-11 9 344E-12 144E-12 9 TR547 409E-12 154E-12 8 107E-12 575E-13 9
Table 62 lists the apparent solubility values of Np in the presence of each cementitious
formulation under both oxidizing and reducing conditions Under oxidizing conditions the cementitious formulation does not appear to have a dramatic effect on the solubility The apparent solubility values are similar to those of Pu under similar conditions except the Np standard deviations are much higher The high standard deviations are an analytical artifact since the measured concentrations were close to or at the detection limit of the ICP-MS There does appear to be a slight decrease in Np solubility under reducing conditions However the statistical significance of this decrease was not calculated
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Table 62 Comparison of neptunium apparent solubility values under oxidizing and reducing conditions
Cement Oxidizing Solubility
(M)
Std Dev of Replicates
Reducing Solubility
(M)
Std Dev of Replicates
Aged Cement 349E-12 506E-12
9 424E-13 139E-13
3
Vault 2 462E-12 510E-12 9 143E-12 184E-12 9 TR545 680E-12 109E-11 6 780E-13 422E-13 7 TR547 534E-13 240E-13 6 407E-13 298E-13 7
Unlike the apparent solubility values of Pu and Np the aqueousatmospheric conditions
and cementitious formulation seem to have an effect on the Tc Kd values (Table 63) Under oxidizing conditions there is not a discernible difference among the different cementitious formulations especially when taking the respective standard deviations into account However when experiments were run under reducing conditions the specific formulation had a noticeable effect The two saltstone samples with the least amount of reducing slag Aged Cement (0 dry-wt- slag) and Vault 2 (17 dry wt- slag) had Kd values which were similar to those observed under oxidizing conditions However the TR547 (45 dry-wt- slag) increased by almost an order of magnitude while the TR545 (90 dry wt- slag) increased by about three orders of magnitude Although the respective standard deviations are large the higher Kd values do appear to be significant
Table 63 Comparison of technetium Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev
of Replicates
Reducing Kd
Std Dev of Replicates
Aged Cement 330 133
9 557 203
8
Vault 2 508 266 9 5569 203 8 TR545 477 239 9 437E+03 366E+03 9 TR547 275 0948 8 316E+01 182E+01 9
Unlike Tc I does not seem to be as affected by cementitious formulation and redox status (Table 64) The only treatment (possible outlier) that does not follow this trend is the Aged Cement under oxidizing conditions This Kd value is higher than the others but also has a much higher standard deviation which when accounted for gives a value similar to the others All other treatments had near identical Kd values irrespective of solid phase or redox condition But again the Aged Cement data cannot be discounted at this time given the possibility of the influence that redox may have on iodine speciation and the strong influence I speciation has on sorption to cementitious materials
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Table 64 Comparison of iodine Kd values under oxidizing and reducing conditions
Cement Oxidizing Kd Std Dev of Replicates
Reducing Kd
Std Dev
of Replicates
Aged Cement 495 380
9 747 482
7
Vault 2 766 353 9 725 419 6 TR545 864 321 9 786 361 7 TR547 817 198 9 371 238 6
70 Summary and Recommendations for Future Work
71 Comparison with Previous Data The increased sensitivity of the ICP-MS over conventional low-energy gamma
spectroscopy or liquid scintillation counting (LSC) analysis allowed for much more accurate Kd values and apparent solubility values in this work than were previously obtainable Generally radioanalytical detection methods start with activities on the order of 103 to 104 counts per minute (cpm) and approach background levels of 1 to 5 cpm for strongly sorbing radionuclides Therefore the accuracy of the Kd value will be the difference in analytical sensitivity when the initial aqueous activity decreases by a factor of approximately 5000 (ie the aqueous activity drops from approximately 5000 cpm to the instrument background of 1 cpm following almost complete sorption) As a result the reported Kd values can only be reliably reported up for a Kd of 103 to 104 This constraint is believed to be the difference between the observed Kd values for 237Np of gt 105 observed in this work when compared with the Kd values between 3000 and 4000 reported by Kaplan et al (2008) A similar observation was made for Pu because 242Pu was used for ICP-MS analysis and 238Pu was used in the work of Kaplan et al (2008) This constrint may account for the different Kd value of gt104 reported in Kaplan et al (2008) compared with the value of gt105 observed in this work
In the case of Tc Kaplan et al (2008) reported a Kd of 023 mLg for Vault 2 under oxidizing conditions and 093 mLg under reducing conditions while the above experiment determined the Vault 2 Kd to be 505 mLg under oxidizing conditions and 557 mLg under reducing conditions Unlike the discrepancy in the Kd values for Np Pu and Tc between the above findings and those in Kaplan et al (2008) the reported Kd values for iodine are similar For Vault 2 Kaplan et al (2008) found 125I to have a Kd of 894 mLg under oxidizing conditions and 715 mLg under reducing conditions These values are similar to the Kd values of 766 mLg and 725 mLg observed under oxidizing and reducing conditions respectively in this work These findings appear to confirm the previously accepted Kd values of 0-10 mLg depending on the cementitious formulation
72 Suggested Future Work The above data demonstrate several areas that require further examination The
increasing Tc Kd values over time dataset suggest that steady state had not been achieved It would be beneficial to determine the amount of time required to reach steady state and allow determination of a more accurate Kd value (an assumption of the Kd construct is that it be measured at steady state) Also kinetic studies of both Tc and I are needed to better understand their respective interactions with the different cementitious formulations As for the I additional
SRNL-STI-2009-00636 Revision 0
49
tests should be performed to test the hypothesis that iodine may in part exist as iodate which may initially sorb to the saltstone then undergo reduction to iodine or iodide and then desorbs causing a decrease in Kd
A final area of future work is to examine the possible causes for the similar behavior of each cementitious formulation despite the different slag content This discrepancy is not only observed in the above experiments but also in Kaplan et al (2008) which is illustrated in Table 31 and by recent work in measurements of saltstone reduction capacity (Roberts and Kaplan 2009) The reduction capacity (units in milli-equivalentsg solid) equivalents of the Aged Cement with no slag is 855 plusmn 101 and adding 10 slag gives a reducing equivalent of 2398 plusmn 311 However increasing the slag content to 23 causes the reducing capacity to increase to 8218 plusmn 81 which is almost equivalent to the 8324 plusmn 49 of the 100 slag Understanding the chemistry behind the reducing capacity of each cementitious formulation will help to define what reactions are important for controlling radionuclide release from the saltstone
80 References Allard B L Eliasson S Hoglund and K Andersson 1984 ldquoSorption of Cs I and actinides in
concrete systemsrdquo SKB Technical Report SKBKBS TR-84-15 DKB Stockholm Sweden
Denham M D I Kaplan and C Yeager2009 ldquoGroundwater radioiodine Prevalence biogeochemistry and potential remedial approachesrdquo SRNL-STI-2009-00463 Savannah River National Laboratory Aiken SC
Dixon K L M A Phifer and J R Harbour 2008 ldquoFY09 PACA Maintenance Program Additional Saltstone Property Testingrdquo SRNL-L3100-2009-00019 Rev0 Savannah River National Laboratory Aiken SC
Fukui M Fujikawa Y and Satta N 1996 ldquoFactors affecting interaction of radioiodide and iodate species with soilrdquo Journal of Environmental Radioactivity 31 199-216
Hoglund S L Eliasson B Allard K Andersson and B Torstenfelt 1985 ldquoSorption of some fission products and actinides in concrete systemsrdquo Mat Res Soc Symp Proc 50 683-690
Kaplan D I 2007 Geochemical Data Package for Performance Assessment Calculations Related to the Savannah River Site WSRC-TR-2006-00004 Rev 1 Washington Savannah River Company Aiken SC
Kaplan D I and Coates J 2007 ldquoPartitioning of Dissolved Radionuclides to Concrete under Scenarios Appropriate for Tank Closure Performance Assessmentsrdquo WSRC-STI-2007-00640 Rev 0 Washington Savannah River Company Aiken SC 29808
Kaplan D I Roberts K Coates J Siegfried M Serkiz S 2008 ldquoSaltstone and concrete interactions with radionuclides Sorption (Kd) desorption and reduction capacity measurementsrdquo SRNS-STI-2008-00045 Savannah River National Laboratory Aiken SC 2008
SRNL-STI-2009-00636 Revision 0
50
Neck V and Kim J I 2001 ldquoSolubility and hydrolysis of tetravalent actinidesrdquo Radiochim Acta 89 1
Powell B A Fjeld R A Coates J T Kaplan D I Serkiz S M 2002 ldquoPlutonium Oxidation State Geochemistry in the SRS Subsurface Environmentrdquo WSRC-TR-2003-00035 Westinghouse Savannah River Company US DOE Savannah River Site Aiken SC
Roberts K A and D I Kaplan 2009 Reduction Capacity of Saltstone and Saltstone Componentsrdquo SRNL-STI-2009-00637 Rev0 Savannah River National Laboratory Aiken SC
Schwehr K A Santschi P H D I Kaplan C M Yeager and R Brinkmeyer 2009 ldquoOrgano-iodine formation in soils and aquifer sediments at ambient concentrationsrdquo Environ Sci Technol 437258-7264
Yoshida S Muramatsu Y and Uchida S 1992 ldquoStudies on the sorption of I-(iodide) and IO3-
(iodate) onto andosolsrdquo Water Air and Soil Pollution 63 321-329
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51
90 Appendix A Data Tables of Radionuclide Sorption to Saltstone under Oxidizing Conditions
The following tables represent data collected for the no solids controls each saltstone and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious formulation data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL- Below Detection Limit lt01 denotes no notable sorption occurred
91 Data Tables for No Solid Controls
Table 91 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1098124271 0588738002 1206 0053613058B 1098518068 3623675578 1168 0329869456C 1095633227 3667254562 1171 033471553D 1084337349 0224089715 1196 0206660515E 1062853037 0217987352 1184 0205096419F 1072807061 0187059704 1185 0174364721G 1047554375 0245110331 1152 002339834H 098857645 0053735822 1154 0054356769
Table 92 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 109812427 0278151513 1202 0025329694B 109851807 1179747464 117 0107394452C 109563323 1149191187 1174 0104888311D 108433735 0061646445 1186 0056851721E 106285304 0051767732 1186 0048706387F 107280706 004514876 1185 0042084697G 104755438 0271974836 115 0025962837H 098857645 0056143201 1148 0275117656
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Table 93 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9689771741 5635730545 1206 058161644B 9847322158 8815567839 1168 0895224884C 9749375678 8872066318 1171 0910013791D 1154111059 1139541421 1196 0987375879E 0998383266 0716244157 1184 0717404009F 0973220964 0598731247 1185 0615205867G 9760929917 0375956436 1152 0038516457H 0982585077 001870128 1154 0019032734
Table 94 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 968977174 4815179672 1202 0496934273B 984732216 811967814 117 0824556972C 974937568 5125187481 1174 0525693916D 115411106 0064698249 1186 0056058946E 099838327 0006926236 1186 0006937452F 097322096 0012723741 1185 0013073846G 976092992 0397124158 115 0040685074H 098258508 003846849 1148 0039150289
Table 95 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9970293475 8758010503 1206 0878410503B 1035795579 9223444824 1168 0890469607C 9756181039 868137711 1171 088983354D 0990946387 09571545 1196 0965899379E 1000848286 0958642075 1184 0957829561F 1000219419 0954324935 1185 0954115584G 1015650402 086718206 1152 0085381944H 1001427944 0917354471 1154 0916046409
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Table 96 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 997029348 9681302845 1202 0971014832B 103579558 1039736502 117 100380473C 975618104 9652179907 1174 0989339975D 099094639 1047989563 1186 1057564341E 100084829 1047120027 1186 1046232522F 100021942 1027134282 1185 1026908959G 10156504 9612163266 115 0946404712H 100142794 1000804551 1148 0999377496
Table 97 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033096997 518501178 1206 0501890122B 1033465548 7276930444 1168 0704128982C 1035728144 8600139369 1171 0830347174D 9981932702 8482630391 1196 008497984E 9880042315 5447287368 1184 0055134251F 9973570039 9041153475 1185 0090651125G 1003615011 4353607551 1152 043379259H 9486339671 5683679634 1154 0059914359
Table 98 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 1033097 3255083399 1202 0315080133B 103346555 6520607126 117 0630945767C 103572814 7637322674 1174 0737386806D 99819327 BDL 1186 NA E 988004231 BDL 1186 NA F 997357004 BDL 1185 NA G 100361501 3438150241 115 0342576606H 948633967 2530184962 1148 0026671878
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92 Data Tables for Vault 2
Table 99 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367044 0001733701 1101 0000163192 2573806
B 1065611835 000212538 1105 0000199452 2067996
C 1014798459 0001323578 1101 0000130428 3278433
D 1035694085 0001381959 1134 0001334331 3034426
E 1132618376 0001099997 1135 0000971199 4108091
F 1005505809 0001101291 114 0001095261 3686045
G 5364163602 0001194136 112 0000222614 178142
H 5370393851 0001095256 1123 0000203943 2029741
I 5494303637 0001659554 1125 000030205 1379743
Table 910 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1062367 00011705 1109 00001102 3812373 B 10656118 00008583 1111 8055E‐05 5121474 C 10147985 00007166 1109 7062E‐05 6055484 D 10356941 0000788 1126 00007609 5324505 E 11326184 00008703 1122 00007684 5193416 F 10055058 00005765 113 00005734 7045016 G 53641636 00007065 1119 00001317 3011367 H 53703939 00007858 1123 00001463 2829396 I 54943036 00008239 1128 000015 2779478
Table 911 Vault 2- neptunium after one day
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
921692635 0005957077 1101 0000646319 65041889170432784 000306662 1105 0000334403 12347769096163751 0002111663 1101 0000232149 18447190968314926 0000867507 1134 0000895894 45223520994314793 0000898163 1135 0000903298 44178520969777681 0000484972 114 0000500086 80796963929661216 0001578688 112 0000401736 98671723911007939 0001115352 1123 0000285183 14510144054091025 0001146601 1125 0000282826 1473233
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55
Table 912 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92169263 00043124 1109 00004679 8986273B 91704328 00012261 1111 00001337 3088793C 90961638 00008395 1109 9229E‐05 4640933D 09683149 0000481 1126 00004967 8159477E 09943148 00005631 1122 00005664 7048587F 09697777 00003397 113 00003503 115357G 39296612 0000686 1119 00001746 2271251H 39110079 00004796 1123 00001226 3374884I 4054091 00011432 1128 0000282 1477611
Table 913 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9256597482 8294548724 1101 0896068857 6565531 B 9220605132 8284935394 1105 0898524042 631461 C 9328322619 8280953522 1101 0887721604 7274366 D 1041945759 0974835903 1134 0935591795 2958653 E 1023734743 0961438092 1135 0939147663 2759052 F 097395176 0832434488 114 0854697864 7034554 G 4880291057 4145068165 112 0849348557 7809823 H 4837797242 4288579455 1123 0886473583 6107532 I 4738827116 3781772577 1125 0798039786 1137228
Table 914 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92565975 78650338 1109 08496679 9123867B 92206051 80394456 1111 08719 7715476C 93283226 8120385 1109 08705086 8226739D 10419458 09591407 1126 09205284 3667817E 10237347 09375635 1122 09158266 3841864F 09739518 08407776 113 08632641 6565308G 48802911 40565827 1119 08312174 8828343H 48377972 42645053 1123 08814973 6371143I 47388271 36819451 1128 07769739 1278797
SRNL-STI-2009-00636 Revision 0
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Table 915 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9946530213 668522424 1101 0644950246 219202 B 9842972041 6827479432 1105 0665719094 2079681 C 1370633906 128925931 1101 0899565656 4668908 D 9327895369 9578419326 1134 1022618541 lt01 E 9939172266 8563510014 1135 0857892433 6496328 F 9441369098 830634865 114 0876223604 5620694 G 4841170487 4341708968 112 0879296934 5525112 H 4828043618 4502906342 1123 0914490246 3871429 I 500263811 3959869628 1125 0775848285 1176974
Table 916 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99465302 84929996 1109 08193535 8778888B 9842972 84531183 1111 08242284 8832374C 13706339 12003449 1109 08375266 8112402D 93278954 90828797 1126 09697134 127742E 99391723 89516549 1122 08967768 4514156F 94413691 7623566 113 08041979 9687715G 48411705 41571485 1119 08419192 7557309H 48280436 42801299 1123 08692468 6227932I 50026381 38002219 1128 07445689 139756
Table 917 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1046580588 0026580976 1181 0002539793 1702263 B 104436762 0010478566 1183 0001003341 4259487 C 1049080459 0006700641 118 0000638716 6366025 D 113124665 0004242148 12 0003749977 1073492 E 1174037402 0003429046 1199 000292073 1345371 F 1101694915 0002227889 1198 0002022238 1940359 G 5448687281 0002419858 1186 0000444118 9389651 H 5342234695 0001490989 1188 0000279095 1478928 I 5388454776 0002074015 1189 00003849 1087042
SRNL-STI-2009-00636 Revision 0
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93 Data tables for saltstone TR545
Table 918 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10465806 00330348 1188 00031565 1368879B 10443676 00114086 1185 00010924 3911924C 10490805 00062925 1185 00005998 6779161D 11312466 00044912 1197 00039702 1013734E 11740374 00029871 12 00025443 1544978F 11016949 00040505 1206 00036766 1065501G 54486873 00020968 1196 00003848 1083704H 53422347 00019612 1196 00003671 1124225I 53884548 00017107 1194 00003175 1317955
Table 919 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9264165178 402285E‐05 1181 434238E‐06 9980817 B 9352537276 0000110618 1183 118276E‐05 3616813 C 9363541597 705331E‐05 118 753273E‐06 5401186 D 0993110568 BDL 12 NA NA E 0977247222 300794E‐05 1199 307797E‐05 1280331 F 0962441315 BDL 1198 NA NA G 4059128499 BDL 1186 NA NA H 4065161486 705198E‐05 1188 173473E‐05 2380003 I 4116819691 0000110748 1189 269014E‐05 1555864
Table 920 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92641652 NA 1188 NA NA B 93525373 00001935 1185 2069E‐05 2067199C 93635416 4119E‐05 1185 44E‐06 9247818D 09931106 BDL 1197 NA NA E 09772472 BDL 12 NA NA F 09624413 00066817 1206 00069424 562421G 40591285 00003289 1196 8103E‐05 5148274H 40651615 00025316 1196 00006228 6625737I 41168197 00001018 1194 2474E‐05 1692126
SRNL-STI-2009-00636 Revision 0
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Table 921 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9655146069 820460082 1181 0849764546 8998984 B 9356176321 7703053505 1183 0823312135 1051242 C 9114122586 7978297395 118 0875377451 7062663 D 1042349157 0853053814 12 0818395456 9099556 E 0983206046 0871198263 1199 0886079033 5196709 F 0905148405 0803451372 1198 0887646013 5098696 G 4950156706 4275082341 1186 0863625658 7213934 H 4889067068 4173762594 1188 0853693053 7687519 I 4854463762 4147024058 1189 0854270268 7771045
Table 922 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 96551461 80911855 1188 08380179 9713902B 93561763 74410368 1185 07953075 1234203C 91141226 75881085 1185 0832566 9452625D 10423492 08195966 1197 07862975 1111505E 0983206 08251481 12 08392422 7678853F 09051484 08066411 1206 089117 4923541G 49501567 44733496 1196 09036784 5072867H 48890671 43558824 1196 08909435 5665444I 48544638 43264547 1194 08912323 5739026
Table 923 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9712446639 8458491376 1181 0835627421 7856457 B 9921185946 8575189634 1183 0829335063 8520183 C 9955720475 9174749665 118 0884380649 5450116 D 1022494888 1054151374 12 1026487576 lt01 E 1003068795 9253307262 1199 0918551075 3480297 F 8952017188 8148352848 1198 0906576684 4096805 G 4940393083 4349637713 1186 0862852934 6406294 H 4840176398 4349559364 1188 0880930756 5580958 I 4991209221 4362736266 1189 0856667235 6817707
SRNL-STI-2009-00636 Revision 0
59
Table 924 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 97124466 81545995 1188 08056055 9637661B 99211859 79482276 1185 07686995 1245818C 99557205 83867718 1185 08084252 9879D 10224949 98946711 1197 09635008 154859E 10030688 86788315 12 08615244 63087F 89520172 75300141 1206 0837781 7697785G 49403931 41351764 1196 08203095 8828858H 48401764 39421041 1196 07984075 1042559I 49912092 40122049 1194 07878369 1097334
94 Data Tables for Saltstone TR547
Table 925 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1048950046 0002141023 1149 0000204111 2112281 B 1039943573 0001770549 1157 0000170254 2460487 C 1084651695 0001127533 1153 0000103953 4014918 D 1088686867 0001201087 1172 0001103244 3564524 E 1119673887 0000783288 1177 0000699568 5709897 F 1045722787 0000914861 1181 000087486 4495324 G 5387981131 0001444832 1169 0000268158 1494715 H 5412748988 0001143483 1169 0000211257 1965749 I 5373948758 00010003 1164 0000186139 2280472
SRNL-STI-2009-00636 Revision 0
60
Table 926 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 104895 NA 116 NA NA B 10399436 0001828 1165 00001758 2383132C 10846517 00010788 1164 9946E‐05 4196159D 10886869 00009131 1184 00008388 4689778E 11196739 00010624 1189 00009488 4208928F 10457228 00007967 1191 00007619 516258G 53879811 00007915 1173 00001469 2728993H 5412749 00008355 1175 00001544 2690641I 53739488 00006103 1174 00001136 3737892
Table 927 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772032 0000454463 1149 473903E‐05 9116335 B 9293228768 0000260081 1157 27986E‐05 1499475 C 1008725504 0000302018 1153 299405E‐05 1397125 D 0952173007 000019177 1172 0000201403 1954603 E 0992224074 BDL NA NA F 0967815522 402137E‐05 1181 41551E‐05 9474699 G 4068405786 0000222282 1169 546361E‐05 7336986 H 409543171 0000531619 1169 0000129808 3199152 I 4017406611 0000410123 1164 0000102086 4157807
Table 928 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9589772 NA 116 NA NA B 92932288 00002145 1165 2308E‐05 1818463C 10087255 00001628 1164 1614E‐05 2591215D 0952173 BDL 1184 NA NA E 09922241 BDL NA NA F 09678155 5107E‐05 1191 5277E‐05 7460375G 40684058 00001336 1173 3284E‐05 1220544H 40954317 8151E‐05 1175 199E‐05 2086795I 40174066 00001322 1174 3292E‐05 1289605
SRNL-STI-2009-00636 Revision 0
61
Table 929 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9466799266 8233850788 1149 0869760788 8220086 B 9439556236 817653394 1157 0866198975 8165745 C 9383493063 8086024379 1153 0861728604 8430884 D 1061939876 0919992065 1172 0866331594 6241759 E 0991827343 0836511397 1177 0843404251 7590958 F 0971981155 0839862696 1181 0864073024 6354378 G 4883337077 414858839 1169 0849539633 7903986 H 4691440077 3996173112 1169 0851800949 8038249 I 486993937 4291285586 1164 0881178442 6558707
Table 930 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94667993 NA 116 NA NA B 94395562 85812109 1165 09090693 5885474C 93834931 84622373 1164 09018217 6279204D 10619399 09580683 1184 09021869 4435663E 09918273 08881507 1189 08954691 4835506F 09719812 09036489 1191 0929698 3138862G 48833371 4490415 1173 09195382 4312104H 46914401 42054182 1175 08964024 5612948I 48699394 43843193 1174 09002821 5536503
Table 931 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9944920441 8813152965 1149 0886196427 738241 B 9956006121 8747156303 1157 0878580848 8007767 C 9822152291 8664470934 1153 0882135674 7988892 D 1002391846 9333490632 1172 0931121963 3368509 E 9918273427 6625075445 1177 0667966607 1551748 F 9918175056 8931364957 1181 0900504872 4773862 G 5166570628 4445386532 1169 0860413387 7961604 H 4847821413 410447427 1169 084666367 8664303 I 4850381381 4266693706 1164 0879661489 6413801
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Table 932 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 99449204 84078927 116 0845446 9304586B 99560061 84339692 1165 08471237 9547302C 98221523 82821547 1164 08432118 9915886D 10023918 89006508 1184 08879413 5357117E 99182734 84480287 1189 0851764 703665F 99181751 85844767 1191 08655299 6384908G 51665706 41857945 1173 08101688 1046071H 48478214 40068924 1175 08265347 9670412I 48503814 43218665 1174 08910364 5894162
95 Data Tables for Aged Cement
Table 933 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1049661917 000057716 1167 549853E‐05 7570833 B 1044676116 0000712674 1154 682196E‐05 634071 C 1040494422 0000659215 1163 633559E‐05 6857795 D 1069574815 0000501161 1181 0000468561 8743806 E 1119884926 0000459622 1182 0000410419 9611808 F 1132798521 0000428241 1184 0000378038 1056264 G 5494249954 0000427061 117 777287E‐05 5287854 H 5407466468 0000325564 1169 602064E‐05 6993736 I 53502419 0000692442 117 0000129423 3210102
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Table 934 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 10496619 00007248 1167 6905E‐05 6028735B 10446761 00005881 1161 5629E‐05 7683924C 10404944 00006194 1161 5953E‐05 7298549D 10695748 00005383 1184 00005033 8139848E 11198849 00005656 1187 0000505 7810696F 11327985 00003573 1188 00003154 1266063G 549425 00003353 1177 6103E‐05 6734657H 54074665 00003576 1176 6612E‐05 6367965I 53502419 00004411 1176 8244E‐05 5039541
Table 935 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9280093212 0007108181 1167 000076596 5439288 B 9320139831 0004011335 1154 0000430394 1006297 C 9508541493 000166325 1163 0000174922 248828 D 097028876 0000726172 1181 0000748408 547375 E 1081890779 0000520905 1182 0000481476 8194895 F 0994472941 0000224317 1184 0000225563 1770803 G 4062063373 0000183026 117 450574E‐05 9120486 H 4091295968 0000223825 1169 547076E‐05 7696036 I 4079362752 0000254574 117 624054E‐05 6657537
Table 936 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 92800932 00038179 1167 00004114 1013042B 93201398 00016426 1161 00001762 2458009C 95085415 00009139 1161 9611E‐05 452898D 09702888 00002133 1184 00002198 1864504E 10818908 00002982 1187 00002756 1431793F 09944729 00003267 1188 00003285 121583G 40620634 00001016 1177 2501E‐05 1642830H 4091296 00001998 1176 4884E‐05 8621078I 40793628 8206E‐05 1176 2012E‐05 2065348
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Table 937 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9416663483 7667114947 1167 0814207172 1117916 B 9465319299 7556377889 1154 0798322555 1266251 C 9569149292 7922749629 1163 0827947123 107987 D 1004295601 0866599278 1181 0862892635 6684472 E 1031694856 0865518891 1182 0838929152 7750351 F 0984134558 0828238515 1184 0841590724 7688585 G 4895111728 4051996638 117 0827763872 9366864 H 4862204917 4190616825 1169 0861875815 758057 I 4886868983 4145489943 117 0848291607 8251034
Table 938 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 94166635 82267024 1167 08736324 7702806B 94653193 85780661 1161 09062627 6210837C 95691493 85417433 1161 08926335 6996406D 10042956 09416563 1184 09376286 2898204E 10316949 09196854 1187 08914316 4979791F 09841346 0886981 1188 09012802 4545372G 48951117 43441484 1177 08874462 602818H 48622049 43653822 1176 08978195 5625012I 4886869 43948285 1176 08993138 5472433
Table 939 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9875081178 4782787653 1167 0484328945 4601018 B 9551280827 1917864389 1154 0020079657 2112282 C 9836817804 2850427319 1163 0028977128 1457909 D 9943520802 5354401206 1181 053848142 3530201 E 992014285 3303880468 1182 0033304767 1145599 F 1004016064 4562722289 1184 0045444714 8391729 G 4856028999 2981077404 117 061389201 266613 H 4871988025 2455078723 1169 0050391723 7941965 I 4877095245 17301515 117 0354750402 7638668
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Table 940 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH
Fraction Aq Kd
A 98750812 44961824 1167 04553059 5148943B 95512808 6813704 1161 07133812 1911392C 98368178 27708852 1161 02816851 1125817D 99435208 71523103 1184 07192935 1616758E 99201429 67909668 1187 06845634 1835712F 10040161 65826354 1188 06556305 2115061G 4856029 27420191 1177 05646628 3249713H 4871988 18538966 1176 03805216 6937195I 48770952 13893489 1176 02848722 1051135
96 Data Tables for Sorption to Vial Walls
Table 941 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 0110121 003628 3294558NS‐B 0110228 00268 2431335NS‐C 0110121 002735 2483632NS‐D 0010863 000335 3083863NS‐E 001065 00035 3286385NS‐F 0010757 000386 3588528NS‐G 0111719 001536 1374878NS‐H 0010544 000313 2968513
Table 942 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 009717 00121 124524NS‐B 009881 000345 3491549NS‐C 009799 00208 2122666NS‐D 0011562 000333 2880125NS‐E 0010004 000316 3158737NS‐F 0009758 000382 3914737NS‐G 0097744 004938 5051972NS‐H 000984 000559 5680894
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100 Appendix B Data Tables of Radionuclide Sorption to Saltstone Under Reducing Conditions
The following tables represent data collected for the no solids controls each cementitious solid and testing of radionuclide sorption to the vial walls The no solids controls tables include the concentration (ppb) of the radionuclide spiked into the sample along with the concentration of the radionuclide (ppb) measured in the aqueous phase after the given equilibration time The pH at the time the sample was taken is also recorded along with the fraction of the radionuclide which stayed in the aqueous phase The tables for the cementitious solidsrsquo data include the data above along with the addition of a Kd value The tables of the data for the radionuclides sorbed to the vial walls include the initial concentration (ppb) of the spike the concentration (ppb) of the radionuclide that had sorbed to the vial wall during the experiment and the percentage of the total concentration this represents Important Notes
BDL= Below Detection Limit lt01 denotes no notable sorption occurred
101 Data Tables for No-Solid Controls
Table 101 Plutonium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0583283525 1178 0059123469NS‐B 9899624212 0663485207 1176 0067021252NS‐C 9800690365 0539915704 1177 0055089558NS‐E 1082582721 0431846663 1166 0398904079NS‐F 1032892193 0000301866 1173 0000292253NS‐G 1052776412 0488809417 1171 0464305061
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Table 102 Plutonium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9865515956 0545394 1183 0055283NS‐B 9899624212 0468747 1179 004735NS‐C 9800690365 0439191 1180 0044812NS‐E 1082582721 0358897 1161 0331519NS‐F 1032892193 0000111 1171 0000107NS‐G 1052776412 455E‐05 1165 432E‐05
Table 103 Neptunium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 2227968645 1178 0227710733NS‐B 9774386849 3506033589 1176 0358696013NS‐C 9748642055 4599509164 1177 0471810242NS‐E 0990926695 0923435978 1166 0931891312NS‐F 1059013829 BDL 1173 NA NS‐G 1015695951 0920736194 1171 0906507694
Table 104 Neptunium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 9784205654 1843735 1183 018844NS‐B 9774386849 2360655 1179 0241514NS‐C 9748642055 440653 1180 0452015NS‐E 0990926695 0846694 1161 0854447NS‐F 1059013829 BDL 1171 NA NS‐G 1015695951 BDL 1165 NA
Table 105 Technetium no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8777467999 1178 0998073653NS‐B 9132734292 8531262277 1176 093414108NS‐C 8608231557 8553778159 1177 0993674264NS‐E 0907236499 0898199858 1166 0990039376NS‐F 0916275429 0000368379 1173 000040204NS‐G 0915720325 0925888607 1171 1011104135
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Table 106 Technetium no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 8794409081 8337459 1183 0948041NS‐B 9132734292 8065824 1179 0883177NS‐C 8608231557 8155761 1180 0947437NS‐E 0907236499 0877529 1161 0967255NS‐F 0916275429 0000146 1171 0000159NS‐G 0915720325 0000238 1165 000026
Table 107 Iodine no solids control after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8432881472 1178 0878675853NS‐B 959688424 8513714171 1176 0887133153NS‐C 9624703316 8757645753 1177 0909913321NS‐E 9624816906 8636792982 1166 0897346211NS‐F 9526296152 9198116117 1173 0965550091NS‐G 9616691794 8327792058 1171 0865972648
Table 108 Iodine no solids control after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
NS‐A 959726097 8650033 1183 0901302NS‐B 959688424 9343247 1179 9735709NS‐C 9624703316 9025099 1180 0937702NS‐E 9624816906 9418273 1161 0978541NS‐F 9526296152 1160028 1171 1217711NS‐G 9616691794 927704 1165 0964681
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102 Data Tables for Vault 2
Table 109 Vault 2- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 94058918 0002841681 1105 0000302117 1403936
B 9602498 0002282224 1110 000023767 1783252
C 9630618675 0002608744 1104 000027088 1571697
D 4945396384 0002082692 1125 0000421137 1009911
E 4964945192 0001703548 1128 0000343115 1202999
F 4441601383 000165649 1120 0000372949 127140
G 1079602045 0001250199 1129 0001158019 3739933
H 1031512133 0003222175 1132 0003123739 1317961
I 0939293925 0001224667 1133 0001303816 3632054
Table 1010 Vault 2- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9405892 0007019 111 0000746258 5681206 B 9602498 0003294 1117 0000342992 123554 C 9630619 0002936 1114 0000304893 1396318 D 4945396 0001795 113 0000363011 1171688 E 4964945 0001373 1131 0000276484 1493015 F 4441601 0001516 113 0000341219 1389674 G 1079602 0001109 1142 0001027508 4215519 H 1031512 0000883 1143 0000855983 4820576 I 0939294 0000978 1143 0001040992 4550255
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Table 1011 Vault 2- neptunium after one day
Sample ID Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq
A 9425042625 0001709054 1105 0000181331 B 9611386476 0001184125 1110 00001232 C 9579553607 0001155517 1104 0000120623 D 4974000414 0000672325 1125 0000135168 E 4916731623 0000675371 1128 0000137362 F 4373142817 0000570681 1120 0000130497 G 0943366414 0000389738 1129 0000413136 H 1011745587 0000565648 1132 0000559081 I 0865252712 0000379545 1133 0000438653
Table 1012 Vault 2- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9425043 0001341 111 0000142314 2985674B 9611386 0000792 1117 823889E‐05 5153394C 9579554 0000363 1114 379197E‐05 1124764D 4974 656E‐05 113 131798E‐05 3231076E 4916732 0000212 1131 43111E‐05 9584756F 4373143 0000252 113 575681E‐05 824464G 0943366 355E‐05 1142 375857E‐05 1153591H 1011746 353E‐05 1143 349083E‐05 1183195I 0865253 202E‐05 1143 233004E‐05 2035123
Table 1013 Vault 2- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1105 098889012 0476492 B 8638001423 7823321167 1110 0905686487 4413063 C 9323317745 925927516 1104 0993130923 0294664 D 442651005 4300859603 1125 0971614106 1242837 E 4426849405 4336992073 1128 0979701742 0855315 F 3929483125 3938204338 1120 100221943 lt01 G 0817864386 081693181 1129 0998859743 0049487 H 0878958929 0792412508 1132 0901535306 4510199 I 0772205665 0871436364 1133 1128502941 lt01
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Table 1014 Vault 2- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 111 0876676186 5966258B 8638001 7419385 1117 0858923768 6960547C 9323318 8036996 1114 0862031802 6818523D 442651 3962629 113 0895203859 4979995E 4426849 4090424 1131 092400338 3395329F 3929483 3698764 113 0941285083 2958172G 0817864 0742066 1142 0907321016 4428077H 0878959 0720997 1143 0820285656 9047228I 0772206 0788286 1143 1020823931 lt01
Table 1015 Vault 2- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849289 7649889866 1105 0873190442 6159384 B 8926622427 7158886295 1110 0801970326 1046384 C 8944822597 719172491 1104 0804009787 1037675 D 4667085975 4379235651 1125 093832333 2796427 E 4500417953 3331662008 1128 0740300577 144803 F 404412292 3051584708 1120 0754572689 1542407 G 1257756141 1042917052 1129 0829188598 8933914 H 9515163608 6458872226 1132 0678797811 1954128 I 8192282988 8640513157 1133 1054713707 lt01
Table 1016 Vault 2- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8760849 787583 111 0898980219 4765962B 8926622 5032039 1117 5637113657 lt01 C 8944823 7134714 1114 079763622 1079982D 4667086 4589269 113 0983326499 072138E 4500418 3745656 1131 0832290717 8317575F 4044123 3214176 113 0794777097 1224497G 1257756 1090023 1142 0866640978 6673619H 9515164 3181754 1143 3343877675 lt01 I 8192283 9333398 1143 1139291501 lt01
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103 Data Tables for TR545
Table 1017 TR545- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216275 0003211762 1178 0000423089 1014432 B 7220544548 0002476226 1181 0000342942 1361143 C 6931442863 0002424369 1184 0000349764 1382125 D 3679791021 0002216217 1187 0000602267 7789595 E 3700656669 0001909447 1184 0000515975 8824483 F 3870057311 0001930251 1179 0000498765 8930885 G 0733093687 0001371053 1188 0001870229 2520255 H 0714539864 0001661534 1187 0002325321 1926446 I 072348416 0001140936 1188 0001577002 2791027
Table 1018 TR545- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7591216 0001366 118 000017994 2385788B 7220545 0001296 1182 0000179541 2600341C 6931443 0000913 1183 0000131752 3669937D 3679791 0000811 1185 0000220318 213020E 3700657 0001047 1186 0000282847 1610155F 3870057 0000474 1183 0000122483 3638147G 0733094 0000602 1187 0000820842 5748256H 071454 0000498 1185 0000697618 6431762I 0723484 0000479 1184 0000662029 665452
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Table 1019 TR545- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194102 0008139809 1178 0008139809 4966049 B 8812043306 0003090249 1181 0003090249 1332911 C 8601491692 0002857833 1184 0002857833 145718 D 4494913172 0002431822 1187 0002431822 8678061 E 4357753634 0001442135 1184 0001442135 1376821 F 4723671527 0000789191 1179 0000789191 2668996 G 091531421 0000557461 1188 0000557461 7750198 H 0912530034 0000387691 1187 0000387691 1056587 I 0908158622 0000165863 1188 0000165863 2413715
Table 1020 TR545- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9407194 0000126 118 133952E‐05 3210587B 8812043 0000303 1182 34346E‐05 1361380C 8601492 0000156 1183 181841E‐05 2663305D 4494913 0000347 1185 772991E‐05 607659E 4357754 906E‐05 1186 207863E‐05 2192696F 4723672 0000207 1183 437691E‐05 1018911G 0915314 91E‐05 1187 99443E‐05 4749023H 091253 BDL 1185 NA NA I 0908159 BDL 1184 NA NA
Table 1021 TR545- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681063 7191335597 1178 0649811028 2313284 B 1042599825 7539402767 1181 0723134858 1787174 C 1016670487 8024108456 1184 0789253603 1291 D 533879659 2448368545 1187 0458599331 5540923 E 5359438061 2197371376 1184 041000033 6554461 F 5582261683 2335905009 1179 0418451363 6192481 G 0935831771 0069557071 1188 0074326469 5880414 H 1063230981 0071395625 1187 0067149685 623756 I 1087754 0052020649 1188 004782391 8777157
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Table 1022 TR545- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 1106681 0688024 118 0062170019 6475252B 10426 3454341 1182 0331319968 9420817C 101667 4315917 1183 0424514804 6554265D 5338797 0081828 1185 0015326992 3015309E 5359438 004523 1186 0008439386 5351528F 5582262 0050094 1183 0008973825 4920748G 0935832 0006073 1187 0006489588 7228512H 1063231 0006007 1185 0005649652 79025I 1087754 0004734 1184 0004352288 1008486
Table 1023 TR545- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 898113225 8487458671 1178 0945032145 2356428 B 9131823285 7621244902 1181 0834580857 8159034 C 9347636536 7457911897 1184 0797839311 1050404 D 4575756317 3594537413 1187 0785561373 1139171 E 4700103984 3660617077 1184 0778837466 1149527 I 496493275 3718275456 1179 0748907517 534887 F 8821518816 7805147159 1188 0884784959 1292627 G 9104387158 688000471 1187 0755680156 9609413 H 9116507166 7366395982 1188 0808028321 1360264
Table 1024 TR545- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8981132 8370881 118 0932051904 2953447B 9131823 7195504 1182 7879592346 lt01 C 9347637 7543793 1183 0807026787 9912517D 4575756 3638427 1185 0795153224 1075088E 4700104 4030471 1186 0857527944 6725678I 4964933 3830102 1183 0771430723 1202095F 8821519 8163764 1187 0925437469 3309513G 9104387 7374992 1185 0810048143 9375302H 9116507 9183809 1184 1007382399 lt01
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104 Data Tables for TR547
Table 1025 TR547- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081035 0001713462 1155 0000233726 2052086 B 7328043805 0000872426 116 0000119053 3978172 C 7071427186 0000766705 1162 0000108423 443366 D 3635696803 0000569848 1165 0000156737 2926072 E 3652534842 0000393375 1166 0000107699 4271111 F 3684343628 0000302746 1163 821708E‐05 5492984 G 0743960581 0000514945 1164 0000692167 6752787 H 0777698097 0000252938 1164 0000325239 1413999 I 0723194348 0000177006 1162 0000244756 1958505
Table 1026 TR547- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 7331081 0000518 1161 707249E‐05 6782639B 7328044 0000412 1164 562039E‐05 8427222C 7071427 0000332 1168 469813E‐05 1023256D 3635697 0000201 1171 553737E‐05 8283164E 3652535 0000192 1170 524331E‐05 8773459F 3684344 0000272 1172 738169E‐05 6114676G 0743961 96E‐05 1173 0000129031 3624479H 0777698 0000121 1170 0000155632 2955469I 0723194 0000187 1173 0000258316 1855673
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Table 1027 TR547- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321113 0000398128 1155 446666E‐05 1073986 B 8957071854 000032779 116 365957E‐05 1294283 C 8627854248 0000337955 1162 391703E‐05 1227315 D 4445064053 0000242059 1165 544558E‐05 8422798 E 4490502056 0000292509 1166 651396E‐05 7061975 F 4459268715 0000676132 1163 0000151624 2976655 G 0900219568 454363E‐05 1164 504725E‐05 9266533 H 0946539946 0000171998 1164 0000181712 2531222 I 0912956209 606879E‐05 1162 66474E‐05 7212463
Table 1028 TR547- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8913321 0000242 1161 271084E‐05 1769639B 8957072 0000116 1164 128974E‐05 3672542C 8627854 0000116 1168 134188E‐05 3582700D 4445064 BDL 1171 NA NA E 4490502 605E‐05 1170 13468E‐05 3415784F 4459269 806E‐05 1172 180709E‐05 2497898G 090022 152E‐05 1173 168369E‐05 2777954H 094654 605E‐05 1170 639353E‐05 7194887I 0912956 BDL 1173 NA NA
Table 1029 TR547- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779962734 1060834347 1155 108470183 0910195 B 9835835051 1050945992 116 10684868 1638845 C 9507654819 1027484967 1162 1080692333 0941248 D 4824820947 507820462 1165 10525167 1843339 E 4872457168 5239952738 1166 1075423048 0880238 F 4913611454 5328321311 1163 1084400214 0509761 G 0962090763 10672488 1164 1109301577 lt01 H 100515912 1062338104 1164 1056885505 1452343 I 0887794331 0990729562 1162 1115944907 lt01
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Table 1030 TR547- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9779963 8774052 1161 0897145797 108521B 9835835 9081111 1164 0923267955 9140247C 9507655 8622742 1168 0906926233 1008659D 4824821 3174345 1171 0657919842 3008172E 4872457 3023902 1170 0620611305 3477241F 4913611 3011782 1172 0612946765 3513874G 0962091 0511292 1173 0531438732 4885935H 1005159 0493115 1170 0490584261 5607747I 0887794 0473141 1173 0532939428 4965678
Table 1031 TR547- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222244 759657507 1155 089096611 5070018 B 8457478089 7831245583 116 0925955173 3298918 C 8454964361 7487755693 1162 0885604643 5222873 D 4263831311 3621172193 1165 0849276608 701438 E 4260937738 362895009 1166 0851678741 6966757 F 4294940694 3595565556 1163 0837163028 7672974 G 8554929637 7623627363 1164 0891138523 4941109 H 8819365709 7733611311 1164 0876889741 5728039 I 8300395228 7352643249 1162 0885818452 5240798
Table 1032 TR547- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8526222 7775594 1161 0911962405 3999451B 8457478 9568055 1164 113131301 lt01 C 8454964 8191721 1168 0968865194 1299343D 4263831 3716515 1171 087163741 5820501E 4260938 6299986 1170 1478544594 lt01 F 4294941 3667886 1172 0854001563 6743887G 855493 8268725 1173 0966545113 1400015H 8819366 9558545 1170 1083813162 lt01 I 8300395 7943227 1173 0956969779 1828191
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105 Data Tables for Aged Cement
Table 1033 Aged cement- plutonium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079224621 0001409021 1150 0000155192 2872173 B 8613004882 00008076 1155 937652E‐05 5131447 C 8541919589 0000863136 1153 0000101047 468296 D 4538279014 0000687826 1156 0000151561 3051697 E 4358905759 0000552396 1158 0000126728 3616109 F 4450334725 0000623348 1158 0000140068 3399577 G 0840653709 0000516994 1160 0000614991 7443306 H 0897570902 0000450005 1160 0000501358 9019731 I 0921814908 0000594538 1162 0000644965 6879445
Table 1034 Aged cement- plutonium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 9079225 0000712 1145 0000155192 5682151B 8613005 0000626 1146 937652E‐05 6617263C 854192 0000454 1146 0000101047 8904598D 4538279 0000394 1155 0000151561 5332446E 4358906 0000314 1156 0000126728 6368014F 4450335 0000237 1155 0000140068 8928327G 0840654 000038 1165 0000614991 1014119H 0897571 0000344 1162 0000501358 1179543I 0921815 0000268 1164 0000644965 1527065
Table 1035 Aged cement- neptunium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444124 0000306309 1150 346133E‐05 1289533 B 8447823057 0000150131 1155 177715E‐05 2711019 C 8590597085 0000199185 1153 231864E‐05 2044057 D 4491250244 517162E‐05 1156 115149E‐05 4020064 E 4391894479 204591E‐05 1158 465838E‐06 9846089 F 4210703646 204376E‐05 1158 485374E‐06 9816203 G 086381524 522216E‐06 1160 604546E‐06 7577764 H 0870501884 BDL 1160 NA NA I 0861953838 BDL 1162 NA NA
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Table 1036 Aged cement- neptunium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8849444 0000131 1145 148418E‐05 3007445B 8447823 0000111 1146 131529E‐05 3662996C 8590597 656E‐05 1146 76328E‐06 6209405D 449125 BDL 1155 NA NA E 4391894 BDL 1156 NA NA F 4210704 BDL 1155 NA NA G 0863815 BDL 1165 NA NA H 0870502 BDL 1162 NA NA I 0861954 BDL 1164 NA NA
Table 1037 Aged cement- technetium after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518355 833290075 1150 098889012 0476492 B 8638001423 7823321167 1155 0905686487 4413063 C 9323317745 925927516 1153 0993130923 0294664 D 442651005 4300859603 1156 0971614106 1242837 E 4426849405 4336992073 1158 0979701742 0855315 F 3929483125 3938204338 1158 100221943 lt01 G 0817864386 081693181 1160 0998859743 0049487 H 0878958929 0792412508 1160 0901535306 4510199 I 0772205665 0871436364 1162 1128502941 lt01
Table 1038 Aged cement- technetium after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8426518 7387328 1145 0876676186 5966258B 8638001 7419385 1146 0858923768 6960547C 9323318 8036996 1146 0862031802 6818523D 442651 3962629 1155 0895203859 4979995E 4426849 4090424 1156 092400338 3395329F 3929483 3698764 1155 0941285083 2958172G 0817864 0742066 1165 0907321016 4428077H 0878959 0720997 1162 0820285656 9047228I 0772206 0788286 1164 1020823931 lt01
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Table 1039 Aged cement- iodine after one day
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418563537 737977259 1150 0876607103 6272787 B 7971671977 6853215035 1155 0859696066 7850152 C 8049572051 705537908 1153 0876491202 6667104 D 4145684267 2980931093 1156 0719044409 1807023 E 4111069758 310676185 1158 075570643 1481422 F 4086431184 3226673231 1158 0789606648 1268657 G 7886778865 6617517673 1160 0839064691 8785091 H 8259334117 6970070149 1160 084390219 8368448 I 839926338 664029369 1162 0790580482 1176026
Table 1040 Aged cement- iodine after four days
Sample ID
Initial Aq Conc (ppb)
Equil Aq Conc (ppb) pH Fraction Aq Kd
A 8418564 76877 1145 0913184256 423658B 7971672 992224 1146 1244687434 lt01 C 8049572 7299231 1146 0906784993 4863719D 4145684 3116002 1155 0751625609 1528223E 411107 351634 1156 0855334565 7750838F 4086431 3293867 1155 0806049742 1145648G 7886779 7759404 1165 0983849604 0751874H 8259334 88239 1162 1068354932 lt01 I 8399263 711941 1164 0847623085 7981093
106 Data Tables for Sorption to Vial Walls
Table 1041 Plutonium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial (ppb)
Sorbed to Walls
NS‐A 8197769521 0082513388 100653462NS‐B 8221312733 00787687 095810368NS‐C 8126405694 0074648839 091859602NS‐E 0892430451 0003210839 035978593NS‐F 0851281521 0002677402 031451429NS‐G 0867134776 0002050021 023641316
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Table 1042 Neptunium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1001822029 0056017 0559151NS‐B 1000816271 0036572 0365421NS‐C 9982091832 0029872 0299253NS‐E 1005570326 0000511 0050771NS‐F 1074652687 000057 0053056NS‐G 1030704749 0000249 0024193
Table 1043 Technetium sorbed to vial wall in no solids control
Sample ID
Initial Conc (ppb)
Conc In Wash of Vial
Sorbed to Walls
NS‐A 1179928939 555806E‐05 000047105NS‐B 12253209 774746E‐05 000063228NS‐C 115498292 485721E‐05 000042054NS‐E 1206356364 490926E‐06 000040695NS‐F 1218363059 399779E‐06 000032813NS‐G 1217636322 381518E‐06 000031333
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110 Appendix C Dixon et al (2009) FY09 PACA Maintenance Program Additional Saltstone Property Testing SRNL L3100-2009-00019 Rev 0
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SRNL L3100-2009-00019 Rev 0
December 16 2008
Keywords Performance Permeability Modulus
L B Romanowski
Waste Determinations From K L Dixon M A Phifer and J R Harbour
FY09 PACA Maintenance Program Additional Saltstone Property Testing
BACKGROUND
Additional tests have been identified for measurement of important hydraulic and physical properties of saltstone The initial phase of this work [1] was completed last year and the results were detailed in an internal report [2] The proposed testing for FY09 includes measurement of saturated hydraulic conductivity porosity bulk density particle density water retention and Youngrsquos modulus of simulated Saltstone grouts For completeness the bleed volumes and gel times for each mix will also be measured
The testing will be based on a projected salt solution composition for the ARPMCU stream that will be fed to the Saltstone Production Facility over the next few years The scope for FY09 will include testing to determine the impact of (1) admixtures (2) organics (3) wcm ratio (4) aluminate concentration and (5) temperature of curing on the hydraulic properties of saltstone mixes Samples of selected batches prepared as part of this task will be provided to Dan Kaplan for measurement of Kd through leaching tests The eleven mixes that will be batched and tested are detailed in Table 1
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Table 1 The Eleven Mixes That will be Batched and Tested
Mix
Simulant Descriptor wcm Aluminate BFS FA PC
Type ratio molarity wt wt wt
1 ARPMCU Control - BFSPC 060 0054 90 0 10 2 ARPMCU Baseline 060 0054 45 45 10 3 ARPMCU Baseline with Admixtures 060 0054 45 45 10 4 ARPMCU Baseline with Organics 060 0054 45 45 10 5 ARPMCU Baseline Combo -Organics and Admixtures 060 0054 45 45 10 6 ARPMCU wcm ratio impact 055 0054 45 45 10 7 ARPMCU wcm ratio impact 065 0054 45 45 10 8 ARPMCU Impact of Aluminate 055 0280 45 45 10 9 ARPMCU Impact of Aluminate 065 0280 45 45 10 10 ARPMCU Baseline Combo and Aluminate 060 0280 45 45 10 11 ARPMCU Baseline Combo at 60 oC Cure Temp 060 0054 45 45 10
BFS is Blast Furnace Slag FA is Fly Ash and PC is Portland Cement
TEST DETAILS
Test 1 Control (Mix 1)
A control mix will be based on the baseline mix modified by exclusion of the Class F fly ash Consequently the cementitious materials premix will be a mixture of 90 blast furnace slag and 10 portland cement The degree of reaction will be much greater than with the normal premix and therefore should result in a lower porosity and a lower permeability This bounding test at 060 wcm ratio is expected to yield a hydraulic conductivity at or below the detection limit for the Mactec permeameter measurement system Therefore this test should demonstrate the lowest level of detection of the Mactec system as well as show a resolvable difference between measurements of the control mix and the control mix with the normal premix composition
Test 2 ndashImpact of Admixtures (Mixes 2 and 3)
Recent saltstone batches have required both a set retarder (Daratard 17) and an antifoam agent (Q2) for processing of the saltstone Therefore the baseline mix will be prepared with and without nominal levels of these two admixtures to determine whether these admixtures appreciably affect the hydraulic and physical properties of saltstone at these nominal concentrations
Test 3ndashImpact of Organics (Mixes 2 and 4)
The solvent extraction process is expected to result in some carryover of organics [3]
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Consequently a test will be performed on the impact of Caustic Side Solvent Extraction (CSSX) organics at 100 microliters per 1600 gram batch The CSSX solvent consists of 075 M 1-(2233-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) and 0003 M tri-n-octylamine (TOA) in an Isoparreg L diluent Test 4ndashImpact of Combination of Admixtures and Organics (Mixes 2 5 10 and 11)
This test will determine the impact of a combination of admixtures (Test 2) and organics (Test 3) together in the mix vs the baseline case without admixtures and organics
Test 5ndash Impact of wcm Ratio (Mixes 2 6 and 7)
It is well known that decreasing the wcm ratio in a mix will improve permeability in normal portland cement water mixes This test will measure the variation in permeability for the case of the MCU salt solution at three different wcm ratios The initial selection of wcm ratios is 055 060 and 065 However if the mix at an as-batched 065 wcm ratio has significant bleed water and the resulting actual wcm ratio is close to 060 then the three ratios will be adjusted to provide a more evenly spaced set of values However the baseline mix at 060 will be included as one of the three mixes
Test 6 ndash Impact of Aluminate Concentration (Mixes 8 9 and 10)
The DWPF has modified its process flowsheet to include a caustic washing of HLW sludge to remove some of the aluminum from the HLW prior to vitrification The resulting aluminate stream will then be blended with tank 50 material and fed to the SPF This increased aluminate concentration in the salt solution has significant impact on heat of hydration and set times and consequently it is likely that it will also impact permeability Therefore a set of three samples will be made at wcm ratios of 055 060 and 065 (as in Test 3) with a higher level of aluminate (028 M) for testing
Test 7 ndash Impact of Increased Curing Temperature (Mix 11)
In an ongoing task there is evidence that Youngrsquos modulus (a performance indicator) [4] is reduced by increasing the curing temperature of the mix Since the vault temperature increases during curing as a result of the exothermic hydration reactions one of the baseline mixes with a combination of admixtures and organics will be cured at 60
o
C rather than the normal 22
o
C to determine the impact of curing temperature on the permeability
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SCHEDULE
The schedule for the task of batching and testing of the samples is provided in Table 2 This schedule is based on the fact that the cementitious materials will be available for the testing as needed
Table 2 Additional Saltstone Hydraulic and Physical Property Tests
Item Schedule Start Work 12108 Test Plan Complete 1509 Preparation of 1st set of Samples Complete 11909 90-Day Cure Period for 1st set of Samples Complete 42009
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DISTRIBUTION Savannah River Site
A B Barnes 999-W Rm 336 H H Burns 999-W Rm 381 B T Butcher 773-43A Rm 212 A D Cozzi 999-W Rm 337 D A Crowley 773-43A Rm 216 M E Denham 773-42A Rm 218 J C Griffin 773-A Rm A-231 J R Harbour 999-W Rm 348 C A Langton 773-43A Rm 219 M H Layton 705-1C Rm 14 D I Kaplan (3 copies) 773-43A Rm 215 S L Marra 773A Rm A-230 A M Murray 773-A Rm 229 K A Roberts 773-43A Rm 225 T C Robinson 705-1C Rm 13 L B Romanowski 705-1C Rm 19 K H Rosenberger 705-1C Rm 16 F M Smith 705-1C Rm 24 RPA File (2 copies) 773-43A Rm 213
Clemson University Environmental Engineering and Earth Sciences 372 Computer Court LG Rich Environmental Laboratory Anderson SC 29625
M S Lilley (3 Copies) B A Powell (3 Copies)