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Nick Beresford (CEH) Slide 2 Give an overview of what may impact on assessment results using the available approaches In part based on things we know are being done Consider chronology of development, misuse of default values, double accounting, screening tier application Not considering dispersion modelling and sampling strategies www.ceh.ac.uk/PROTECT Slide 3 Environmental Radiological assessment approaches have developed rapidly over the last 10 y A number of approaches have been made freely available Some of these have been superseded But they are still available & are being used www.ceh.ac.uk/PROTECT Slide 4 UK Environment Agency R&D128 - 2001 Spreadsheet model for limited number of radionuclides Comparatively limited review to derive CR values Dosimetry methods similar to later approaches Environment Agency Sp1a 2003 Supports R&D128 including derivation of complete CR data sets using a guidance approach (can be extremely conservative) www.ceh.ac.uk/PROTECT Slide 5 Europe FASSET (EC) 2001-2004 Establish a framework for radiological environmental protection from source characterisation interpretation, including: Tabulated CR and DCC values for: radionuclides of 20 elements circa 30 reference organism in 7 ecosystems Developed the on-line FASSET Radiation Effects Database www.ceh.ac.uk/PROTECT Slide 6 Europe EPIC (EC) 2000-2003 Establish a framework for radiological environmental protection for the Arctic Ran concurrent to FASSET and shared CR database Although presented differently and for only 12 radionuclides DCCs derived by a different method Allowed participation of Russian institutes leading to EPIC effects database www.ceh.ac.uk/PROTECT Slide 7 Europe ERICA (EC) 2004-2007 Developed the CR and effects (FREDERICA) databases from FASSET & EPIC Developed FASSET dosimetry methodology Adapted guidance for selecting missing CRs from EA SP1a Output - the ERICA Tool implementing the ERICA Integrated Approach More generic ecosystem types (because of lack of data) than FASSET and adapted reference organism list (to encapsulate European protect species & remove some unjustified sub-categories) Derived 10 Gy/h screening dose rate (by SSD) Being maintained and updated www.ceh.ac.uk/PROTECT Slide 8 Europe ERICA (EC) 2004-2007 Developed the CR and effects (FREDERICA) databases from FASSET & EPIC Developed FASSET dosimetry methodology Adapted guidance for selecting missing CRs from EA SP1a Output - the ERICA Tool implementing the ERICA integrated approach More generic ecosystem types (because of lack of data) than FASSET and adapted reference organism list (to encapsulate European protect species & remove some unjustified sub-categories) Being maintained and updated www.ceh.ac.uk/PROTECT ERICA supersedes both FASSET and EPIC outputs & EA state intention to move to ERICA (parameters) rather than develop R&D128 EC PROTECT supported the 10Gy/h screening dose rate using additional data and improved data selection Slide 9 International IAEA (2009-) Developing wildlife transfer parameter handbook and associated on-line database Database will be maintained and updates released annually www.ceh.ac.uk/PROTECT Slide 10 International IAEA (2009-) Developing wildlife transfer parameter handbook and associated on-line database Database will be maintained and updates released annually ICRP Committee 5 (2005-) Developing a framework (ICRP-108) Currently provided tabulated DCC values (using ERICA methodology) and summarised effects information Draft report presenting CR values for RAPs currently with main Commission www.ceh.ac.uk/PROTECT Will be used to update the ERICA Tool CR values (and recalculate EMCLs) Slide 11 USA USDOE Graded Approach (2002) Initially supported by BCG-Calculator spreadsheet model. Still available but replaced by: RESRAD-BIOTA Limited and conservative CR values for generic organisms RESRAD-BIOTA v1.5 (2009) includes values from the ERICA CR database in supporting documentation for application in uncertainty analysis www.ceh.ac.uk/PROTECT Slide 12 Use out of date approaches unless you can justify why they have been used, e.g.: OK to use R&D128 for noble gases Not OK to use FASSET CR values because they offer more refined reference organism list/ecosystem range (theres a reason these were not included in ERICA) www.ceh.ac.uk/PROTECT Slide 13 To serve the purpose for which they were intended RESRAD-BIOTA, R&D128(SP1a) and the ERICA Tool give a complete list of radionuclide-organism transfer parameters. ERICA Tool and R&D128 missing values derived using guidance approaches. These should not be blindly used in higher tier assessments nor should they be picked out for use in other models/recommendations without being clearly identified as such RESRAD-BIOTA Biv values very generic and conservative www.ceh.ac.uk/PROTECT Slide 14 ERICA and R&D128 both clearly identify values which have been derived via guidance approach rather than data But have been taken as values www.ceh.ac.uk/PROTECT Slide 15 Some scope for double accounting associated with daughter product half-life cut-offs e.g. R&D128 includes all 234 Th and 234 U in DCCs for 238 U Entering both 234 Th and 238 U activity concentrations would over estimate dose rates RESRAD-BIOTA and ERICA both offer the user the opportunity to do similar www.ceh.ac.uk/PROTECT Slide 16 Slide 17 Aim - to enable sites of negligible concern to be identified and removed from need for further assessment with a high degree of confidence Envisaged that most sites will only need this level of assessment [i.e. be screened out] www.ceh.ac.uk/PROTECT Slide 18 Input media concentrations compared to predefined concentrations = media concentration giving rise to screening dose rate ERICA: environmental media concentration limits EMCLs RESRAD-BIOTA: biota concentration guidelines BCGs Slide 19 Estimated assuming: Habitat assumption to maximise exposure Probability distributions associated with the default CR and K d databases were used to determine 5th percentile EMCL No conservatism applied to dosimetry For aquatic ecosystems EMCL for water includes consideration of external dose from sediment and that for sediment includes external dose from water and biota-water transfer Slide 20 Estimated assuming: Infinitely large (internal) and small (external) geometries for dose calculations Daughter T 1/2 s up to 100 y included All terrestrial organisms 100% in soil; aquatic 100% water-sediment interface Maximum CR values or 95th percentile CR values predicted using a kinetic-allometric approach Slide 21 Estimated assuming: Infinitely large (internal) and small (external) geometries for dose calculations Daughter T 1/2 s up to 100 y included All terrestrial organisms 100% in soil; aquatic 100% water-sediment interface Maximum CR values or 95th percentile CR values predicted using a kinetic-allometric approach Slide 22 www.ceh.ac.uk/PROTECT Run RESRAD-BIOTA, ERICA Tool and EA R&D128 against 10 Gy/h screening dose rate Data suitable for application in screening tier assessment report maximum media activity concentrations for Four freshwater Three terrestrial scenarios Taken from SENES-WNA report 2007 Slide 23 Activity concentration (Bq l -1 or Bq kg -1 ) FW1FW2FW3FW4 NuclideWaterSedimentWaterSedimentWater Sediment 3H3H5.60x10 4 2.78x10 3 14 C 4.81x10 -1 60 Co2.52x10 -2 1.59x10 2 8.51x10 -2 90 Sr1.60x10 -1 6.00x10 2 7.50x10 -3 9.60x10 -1 2.74x10 -1 106 Ru2.602.32x10 3 8.14x10 -1 131 I1.10x10 -1 1.10 1.44x10 -1 137 Cs8.80x10 -2 2.08x10 3 8.50x10 -3 8.504.44x10 -3 210 Po5.00x10 -2 3.70x10 2 3.70x10 -2 1.51x10 3 234 U ** 8.00x10 -2 2.05x10 1 2.001.00x10 2 3.05x10 -1 2.15x10 4 234 Th *** 8.00x10 -2 1.00x10 2 1.809.10x10 1 3.05x10 -1 2.15x10 4 238 U8.00x10 -2 1.00x10 2 1.809.10x10 1 3.05x10 -1 2.15x10 4 239 Pu9.50x10 -5 5.06x10 1 241 Am5.00x10 -3 5.00x10 1 Slide 24 NuclideT1T2T3 Soil (Bq kg -1 )Air (Bq m -3 )Soil (Bq kg -1 )Groundwater (Bq m -3 ) Soil (Bq kg -1 ) 3H3H6.59x10 2 4.81x10 7 7.00x10 9 14 C4.81x10 -1 2.16x10 3 2.37x10 6 60 Co4.52x10 2 90 Sr1.85 137 Cs1.80x10 2 2.85x10 1 234 U ** 6.09x10 4 6.08 234 Th *** 9.40x10 3 6.08 238 U9.40x10 3 6.08 239 Pu7.00 Slide 25 EA R&D128RESRAD-BIOTAERICA Tool Radionuclide Most exposed groupRQ Most exposed groupRQ Most exposed groupRQ FW1 3H3HAll organisms5.5x10 -2 Riparian animal2.3x10 -2 Phytoplankton1.6x10 -1 60 CoBacteria9.5x10 -3 Aquatic animal1.9x10 -2 Insect larvae1.3 90 Sr Amphibian, Duck4.5x10 -2 Riparian animal1.7x10 -1 Insect larvae4.9x10 -2 106 RuDuck1.8x10 1 n/iInsect larvae2.0x10 1 137 CsDuck4.2x10 -1 Riparian animal3.0x10 -1 Insect larvae1.7 131 IDuck9.1x10 -4 Riparian animal8.9x10 -4 Phytoplankton5.3x10 -3 210 Po Large benthic crustacean, Small benthic crustacean, Benthic mollusc8.5x10 1 Aquatic animal1.5x10 -1 Bivalve mollusc1.8x10 1 234 Un/aAquatic animal4.3x10 -1 Vascular plant6.4x10 1 234 Thn/a Insect larvae8.6x10 1 238 U Amphibian, Duck1.3x10 2 Aquatic animal3.9x10 -1 Vascular plant2.7x10 2 239 PuAmphibian3.0x10 -1 Riparian animal9.5x10 -4 Phytoplankton8.0x10 -2 241 Am Amphibian, Duck2.5Aquatic animal1.2x10 -2 Phytoplankton1.9 SUM2.4x10 2 1.54.6x10 2 Slide 26 EA R&D128 + RESRAD-BIOTAERICA Tool Radionuclide Most exposed groupRQ Most exposed groupRQ Most exposed groupRQ FW2 90 SrDuck5.7x10 -4 Riparian animal3.1x10 -3 Insect larvae2.1x10 -3 137 CsDuck1.7x10 -3 Riparian animal4.3x10 -2 Insect larvae1.1x10 -3 234 Un/aAquatic animal1.1x10 1 Vascular plant3.1x10 2 234 Thn/a Insect larvae1.9x10 3 238 UDuck1.2x10 2 Aquatic animal8.7Vascular plant2.4x10 2 SUM1.2x10 2 1.9x10 1 2.5x10 3 Slide 27 EA R&D128 + RESRAD-BIOTAERICA Tool Radionuclide Most exposed groupRQ Most exposed groupRQ Most exposed groupRQ FW3 3H3HAll organisms2.7x10 -3 Riparian animal1.1x10 -3 Phytoplankton8.1x10 -3 14 CDuck1.0x10 -2 Riparian animal8.5x10 -2 Bird3.1x10 -2 60 CoBacteria2.6x10 -2 Aquatic animal3.1x10 -2 Insect larvae4.6 90 SrDuck2.1x10 -2 Riparian animal1.1x10 -1 Insect larvae7.8x10 -2 106 RuDuck6.2x10 -1 n/iInsect larvae6.4 131 IDuck1.2x10 -3 Riparian animal1.2x10 -3 Phytoplankton6.9x10 -3 137 CsDuck8.9x10 -4 Riparian animal1.1x10 -2 Insect larvae8.7x10 -2 SUM6.9x10 -1 2.4x10 -1 1.1x10 1 Slide 28 EA R&D128RESRAD-BIOTAERICA Tool Radionuclide Most exposed groupRQ Most exposed groupRQ Most exposed groupRQ FW4 210 Po Large benthic crustacean, Small benthic crustacean, Benthic mollusc3.5x10 2 Aquatic animal1.1x10 -1 Bivalve mollusc1.4x10 1 234 Un/aAquatic animal1.6Vascular plant6.7x10 4 234 Thn/a Insect larvae3.3x10 2 238 UDuck2.9x10 4 Aquatic animal2.0Vascular plant5.7x10 4 SUM2.9x10 4 4.61.3x10 5 Slide 29 EA R&D128RESRAD-BIOTAERICA Tool Radionuclide Most exposed groupRQ Most exposed groupRQ Most exposed groupRQ FW4 210 Po Large benthic crustacean, Small benthic crustacean, Benthic mollusc3.5x10 2 Aquatic animal1.1x10 -1 Bivalve mollusc1.4x10 1 234 Un/aAquatic animal1.6Vascular plant6.7x10 4 234 Thn/a Insect larvae3.3x10 2 238 UDuck2.9x10 4 Aquatic animal2.0Vascular plant5.7x10 4 SUM2.9x10 4 4.61.3x10 5 U-238 ERICA Tool and EA R&D128 RQ estimated from input sediment; kd value used estimates much higher water activity concentration than observed; RESRAD- BIOTA uses water and sediment inputs separately Slide 30 EA R&D128 + RESRAD-BIOTAERICA Tool Radionuclide Most exposed groupRQ Most exposed groupRQ Most exposed groupRQ FW3 3H3HAll organisms2.7x10 -3 Riparian animal1.1x10 -3 Phytoplankton8.1x10 -3 14 CDuck1.0x10 -2 Riparian animal8.5x10 -2 Bird3.1x10 -2 60 CoBacteria2.6x10 -2 Aquatic animal3.1x10 -2 Insect larvae4.6 90 SrDuck2.1x10 -2 Riparian animal1.1x10 -1 Insect larvae7.8x10 -2 106 RuDuck6.2x10 -1 n/iInsect larvae6.4 131 IDuck1.2x10 -3 Riparian animal1.2x10 -3 Phytoplankton6.9x10 -3 137 CsDuck8.9x10 -4 Riparian animal1.1x10 -2 Insect larvae8.7x10 -2 SUM6.9x10 -1 2.4x10 -1 1.1x10 1 Co-60 (& Ru-106) ERICA Tool k d values >> than values in other two models Slide 31 EA R&D128RESRAD-BIOTAERICA Tool Radionuclide Limiting organismRQ Limiting organismRQ Limiting organismRQ T1 137 CsCarnivorous mammal 3.6x10 -2 Terrestrial animal 9.4x10 -1 Mammal (Deer)5.8x10 -2 234 Un/aTerrestrial animal 1.3Lichen & bryophytes 3.7x10 1 234 Thn/a Grasses & Herbs5.9x10 -2 238 UFungi1.4x10 2 Terrestrial plant6.5x10 -1 Lichen & bryophytes 6.2 239 PuFungi5.8x10 -2 Terrestrial plant6.0x10 -4 Lichen & bryophytes 6.4x10 -3 SUM1.4x10 2 2.94.3x10 1 Slide 32 T2EA R&D128RESRAD-BIOTAERICA Tool 3H3HFungi1.4x10 -1 Terrestrial animal 3.3x10 1 Detritivorous invertebrate 2.5x10 -1 14 CSeed6.3x10 -3 Terrestrial animal 6.0x10 -2 Mammal (Deer)5.8x10 -3 60 CoFungi5.3x10 -2 Terrestrial plant8.0x10 -2 Mammal (Rat)6.1x10 -2 90 SrCarnivorous mammal 5.9x10 -4 Terrestrial animal 8.9x10 -3 Reptile4.9x10 -3 137 CsCarnivorous mammal 5.7x10 -3 Terrestrial animal 1.5x10 -1 Mammal (Deer)9.1x10 -3 SUM2.0x10 -1 3.4x10 1 3.3x10 -1 Slide 33 EA R&D128RESRAD-BIOTAERICA Tool Radionuclide Limiting organismRQ Limiting organismRQ Limiting organismRQ T3 226 RaFungi1.8Terrestrial plant1.1x10 -1 Lichen & bryophytes 1.3x10 -1 234 Un/aTerrestrial animal 1.3x10 -4 Lichen & bryophytes 3.6x10 -3 234 Thn/a Grasses & Herbs3.8x10 -5 238 UFungi8.8x10 -2 Terrestrial plant4.2x10 -4 Lichen & bryophytes 4.0x10 -3 SUM1.91.1x10 -1 1.4x10 -1 Slide 34 T2EA R&D128RESRAD-BIOTAERICA Tool 3H3HFungi1.4x10 -1 Terrestrial animal 3.3x10 1 Detritivorous invertebrate 2.5x10 -1 14 CSeed6.3x10 -3 Terrestrial animal 6.0x10 -2 Mammal (Deer)5.8x10 -3 60 CoFungi5.3x10 -2 Terrestrial plant8.0x10 -2 Mammal (Rat)6.1x10 -2 90 SrCarnivorous mammal 5.9x10 -4 Terrestrial animal 8.9x10 -3 Reptile4.9x10 -3 137 CsCarnivorous mammal 5.7x10 -3 Terrestrial animal 1.5x10 -1 Mammal (Deer)9.1x10 -3 SUM2.0x10 -1 3.4x10 1 3.3x10 -1 H-3 Difference in input options RESRAD-BIOTA = soil (+ groundwater) other two models = air. Soil concentrations in excess of what would be anticipated from air. Slide 35 EA R&D128RESRAD-BIOTAERICA Tool Radionuclide Limiting organismRQ Limiting organismRQ Limiting organismRQ T1 137 CsCarnivorous mammal 3.6x10 -2 Terrestrial animal 9.4x10 -1 Mammal (Deer)5.8x10 -2 234 Un/aTerrestrial animal 1.3Lichen & bryophytes 3.7x10 1 234 Thn/a Grasses & Herbs5.9x10 -2 238 UFungi1.4x10 2 Terrestrial plant6.5x10 -1 Lichen & bryophytes 6.2 239 PuFungi5.8x10 -2 Terrestrial plant6.0x10 -4 Lichen & bryophytes 6.4x10 -3 SUM1.4x10 2 2.94.3x10 1 Organism ERICA Tool and EA R&D128 include organisms with comparatively high CR values (Lichen&Bryophytes, fungi) not included in RESRAD-BIOTA Guidance values Fungi U (& Ra) CR values in R&D128 are guidance values. Values used 10x higher than data for fungi Slide 36 Can be considerable variation in screening tier results Some of variation can be understood: CR and k d (including if 95%ile, maximum, best estimate used) Organism How sediment and water inputs used Input options Exposure geometry Other Tier 1 type approaches being developed Need to compare & understand before application www.ceh.ac.uk/PROTECT Slide 37 Do not use/accept out of date approaches unless justified Ensure no misuse of default values provided by various approaches There are differences between approaches Dosimetric methods tend to give similar results Transfer parameters can add significant variation Screening tiers www.ceh.ac.uk/PROTECT