UST Release Investigation Report · 2009. 11. 1. · The treatment system operated until February...

UST Release Investigation Report

ML&P Operations and Dispatch Center 1201 East First Avenue

Anchorage, Alaska

November 2009

UST Release Investigation Report

ML&P Operations and Dispatch Center 1201 East First Avenue

Anchorage, Alaska

November 2009

Prepared by: Hoefler Consulting Group 3401 Minnesota Drive Suite 300 Anchorage, Alaska 99503 (Project Manager: Bret Berglund, Environmental Scientist: Brent Veltkamp)

Prepared for: Anchorage Municipal Light and Power 1200 E. 1st Avenue Anchorage, Alaska 99501

UST Release Investigation Report ML&P Operations and Dispatch Center

Prepared for Municipal Light & Power i November 2009

TABLE OF CONTENTS

1 INTRODUCTION ............................................................................................................. 1-1

1.1 Site Background...............................................................................................................1-1 1.2 Previous Spills and Investigations ...................................................................................1-2

1.2.1 Gasoline UST Release .....................................................................................................1-2 1.2.2 Used Oil UST Release .....................................................................................................1-2

1.3 Current Regulatory Status................................................................................................1-3 1.4 Site Description and Regional Setting .............................................................................1-3

1.4.1 Geology............................................................................................................................1-3 1.4.2 Hydrogeology ..................................................................................................................1-3 1.4.3 Land Use ..........................................................................................................................1-4

2 UST RELEASE, REMOVAL AND CORRECTIVE ACTIONS...................................... 2-1 2.1 Initial Reported Release and Actions (Water Line Excavation)......................................2-1 2.2 UST Removal...................................................................................................................2-1 2.3 Sampling and Analysis ....................................................................................................2-7 2.4 Data Reporting .................................................................................................................2-8

3 SAMPLE RESULTS ......................................................................................................... 3-1 3.1 Waste Characterization Results .......................................................................................3-1

3.1.1 Product and Water Samples .............................................................................................3-1 3.1.2 Soil Stockpile Results ......................................................................................................3-1

3.2 Site Characterization Results ...........................................................................................3-2 3.2.1 Water Line Excavation Area............................................................................................3-2 3.2.2 UST Excavation Area ......................................................................................................3-2

3.3 Results Discussion ...........................................................................................................3-3 4 SUMMARY AND CONCLUSIONS ................................................................................ 4-1 5 REFERENCES .................................................................................................................. 5-5


Prepared for Municipal Light & Power ii November 2009

LIST OF FIGURES

Figure 1-1 Vicinity Map .............................................................................................................1-5 Figure 1-2 Site Plan ....................................................................................................................1-7 Figure 1-3a Historical Aerial Photographs, 1964 and 1968 .......................................................1-9 Figure 1-3b Historical Aerial Photographs, 1970 and 2002 .....................................................1-11 Figure 2-1 Detailed Site Map with Sample Results....................................................................2-3 Figure 2-2 Cross Section of UST Excavation After Backfilling ................................................2-5

LIST OF TABLES

Table 3-1 Summary of Waste Characterization Samples ...........................................................3-5 Table 3-2 Soil Stockpile Log and Sample Results......................................................................3-7 Table 3-3 Water Line Excavation Laboratory Results, September 4, 2009 ...............................3-9 Table 3-4 UST Excavation Laboratory Results, September 14, 2009......................................3-13

LIST OF APPENDICES

Appendix A 1953 Operations Building Schematic Drawing Appendix B Photograph Log Appendix C ADEC Site Assessment and Release Investigation Summary Form ADEC Underground Storage Tanks Post Closure Notice Appendix D On Compact Disc:

Data Quality Assessment ADEC Laboratory Data Review Checklists

Laboratory Analytical Reports


Prepared for Municipal Light & Power iii November 2009

LIST OF ACRONYMS

AAC Alaska Administrative Code ADEC Alaska Department of Environmental Conservation amsl above mean sea level bgs below ground surface BTEX benzene, toluene, ethylbenzene, and total xylenes COCs contaminants of concern DRO diesel range organics EPA U.S. Environmental Protection Agency GRO gasoline range organics HCG Hoefler Consulting Group mg/Kg milligrams per Kilogram mg/L milligrams per Liter MDL method detection limit ML&P Municipal Light and Power MOA Municipality of Anchorage NA not analyzed/not applicable ND not detected at or above the method reporting limit OBS Oil Burning Specifications PAH polynuclear aromatic hydrocarbons PCB polychlorinated biphenyls PCE tetrachloroethene PID photoionization detector ppm parts per million PQL practical quantitation limit RCRA Resource Conservation and Recovery Act RRO residual range organics TCE trichloroethene TRPH total recoverable petroleum hydrocarbons TSCA Toxic Substances Control Act TSDF Treatment, Storage, and Disposal Facility USCS United Soil Classification System UST underground storage tank VOC volatile organic compound


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Prepared for Municipal Light & Power 1-1 November 2009

1 INTRODUCTION

This report describes the results of a limited release investigation and corrective actions performed during the removal of an inactive underground storage tank (UST) located next to the Anchorage Municipal Light and Power (ML&P) Operations and Dispatch Center Building (Operations Building). The Operations Building is located at 1201 E. 1st Avenue, Anchorage, Alaska (Figure 1-1, Vicinity Map). The UST removal and reporting was performed in September 2009, in accordance with Alaska Department of Environmental Conservation’s (ADEC) UST regulations (18 Alaska Administrative Code [AAC] 78), and applicable sections of the UST Procedures Manual (ADEC 2002).

1.1 Site Background The UST site is located on a parcel of land owned by the Municipality of Anchorage and operated by ML&P. The legal description of the property is Lot 5a, Block 39D, East Addition Anchorage Townsite. It encompasses the street addresses of 1201 and 1121 E. 1st Avenue, and is 238,274 square feet (ft2) in size. A small parcel of land adjacent to the north side of the property is leased by ML&P from the Alaska Railroad. The location of the UST, along with the approximate property fence line boundaries are shown on Figure 1-2, Site Plan. The site is located in an industrial area between 1st Avenue and Ship Creek. The property was developed in the 1960s and has been used by ML&P for storage and support facilities. In addition to the Operations Building, the parcel includes the Vehicle Maintenance Building (garage), built around 1984. The site also contains a warehouse annex north of the Operations Building. The parcel formerly contained a Municipality of Anchorage (MOA) Paint and Sign Shop, which was demolished in 1997. The concrete slab and foundation of this building remain. Historical aerial photographs of the site, dating from 1964 until 2002, are shown in Figures 1-3a and 1-3b. The UST north of the Operations Building was inactive in 2009 and there is limited information regarding its history. The buried tank apparently supplied fuel to a boiler previously located in the northwest corner of the Operations Building. The UST is shown on a facility drawing from 1953, included in Appendix A (M.L. Taylor and P.W. Kilpatrick, Architects 1953). Documentation regarding when the tank was taken out of active service has not been located. In 2009, the area above the UST was a parking lot, and was paved over with asphalt. No piping or access points were visible. A concrete pad believed to have been the base of an electrical transformer is located next to the Operations Building, adjacent to the former UST (see Appendix B, Photograph Log). The original dates of service for the transformer in this location are not known. However, there are maintenance records from 1974 indicating that a transformer was replaced at this location (Matthews 2009, pers. com.). The transformer installed in 1974 did not contain oil with polychlorinated biphenyls (PCBs), and was removed in the mid 1980s. On August 31, 2009, during a construction project to install water lines for a fire suppression system, a dark oil-like fluid began flowing into the project excavation next to the Operations



Building. Upon review of old facility drawings, the inactive UST was identified as the most likely source of the product. The investigations and removal actions described in this report followed soon thereafter.

1.2 Previous Spills and Investigations There have been no previous investigations directly related to the UST or the immediate area prior to 2009. There have been, however, environmental investigations and cleanup of other portions of the land parcel, primarily focused on UST releases. In addition to the inactive UST next to the Operations Building, there were formerly three other USTs located on the property (see Figure 1-2 for locations). These include the following:

� One 4,000-gallon gasoline and one 4,000-gallon diesel UST located beneath a dispensing island on the southeast corner of the Vehicle Maintenance Building (1121 E. 1st Ave); and

� One 500-gallon used oil UST located on the east side of the Vehicle Maintenance Building approximately 100 feet to the north.

1.2.1 Gasoline UST Release On March 29, 1989, a leak was discovered in the 4,000 gallon unleaded gasoline UST. The UST and adjacent diesel UST were subsequently removed. During the UST removals, approximately 400 yd3 of impacted soil were removed from the excavation. In addition, approximately 167,790 gallons of oily water and 850 gallons of fuel were recovered during and after the initial excavation (Shannon & Wilson 2003). In the fall of 1989, nine groundwater monitoring wells, one product recovery well, a groundwater air stripper, and a soil vapor extraction system were installed. The treatment system operated until February 1996. Groundwater monitoring was continued until 2002, when ADEC granted the site No Further Action status based on decreasing groundwater hydrocarbon concentrations. The groundwater well network was left in place at ADEC’s request for future confirmation and closure sampling.

1.2.2 Used Oil UST Release On October 26, 1990, a used oil UST was removed from the east side of the garage. Soil samples collected during the UST removal indicated significantly elevated petroleum hydrocarbons (5,700 milligrams per Kilogram [mg/Kg] total recoverable petroleum hydrocarbons [TRPH]) and low levels of trichloroethene (TCE) and tetrachloroethene (PCE) at the excavation limits. In 1992, additional sampling showed similar soil contamination and chlorinated solvents in the groundwater at concentrations ranging from 4.7 �g/L to 9.0 �g/L for PCE and 27 �g/L to 48 �g/L for TCE (Shannon & Wilson 2003). In October 1993, three additional monitoring wells (B-1, B-2, and B-3) were installed at locations surrounding the former UST to further define the extent of PCE and TCE in the groundwater (Shannon & Wilson 1993). The highest concentrations were detected in well B-2, located nearest the former UST, with PCE concentrations of 0.025 milligrams per Liter (mg/L) and TCE at 0.043 mg/L. These concentrations exceeded ADEC groundwater cleanup levels. Quarterly sampling and analysis of well B-2 for TCE and PCE was initiated in 2002. Both compounds have continued to exceed the ADEC groundwater cleanup levels (18 AAC 75.345, Table C). There is no clear indication that concentrations are significantly decreasing and



approaching cleanup levels. In July 2009 (the most recently reported sampling event), the groundwater sample from well B-3 contained 0.0159 mg/L TCE and 0.0356 mg/L of PCE. The ADEC groundwater cleanup level for these two compounds is 0.005 mg/L. Cis-1,2-dichloroethene (cis-1,2-DCE) was also detected in July 2009, but below the associated cleanup level. Cis-1,2-DCE is a daughter product of the reductive dechlorination of TCE and PCE (Hoefler Consulting Group [HCG] 2009a). In a separate investigation, an Environmental Protection Agency (EPA) contractor installed well points west of the former waste oil tank to evaluate the former tanks contribution to vinyl chloride contamination detected downgradient (west) of the UST site. The results of the investigation indicated the solvent contamination from the waste oil tank degrades rather quickly and the contaminant plume is generally attenuated a short distance from the source area and is not responsible for the chlorinated solvent plume (CH2M HILL 2008). This site is still an active site in the ADEC contaminated sites database (Hazard ID 23606).

1.3 Current Regulatory Status The Operations Building UST site was recently added (9/16/09) as an active site in the ADEC contaminated sites database. The Hazard ID is 25453.

1.4 Site Description and Regional Setting The site lies adjacent to Ship Creek, approximately one mile upstream from its outlet into the Knik Arm of Cook Inlet. The site is relatively flat with an elevation of approximately 35 feet above mean sea level (amsl). Surface drainage at the site is generally to the northwest toward Ship Creek. However, direct runoff to the creek is impeded by an earthen embankment along the north edge of the property (see Figure 1-2, “Pole Yard” area). At its nearest point, Ship Creek is located approximately 300 feet from the northern edge of the UST excavation site; the creek elevation is approximately 10 feet below the average surface elevation of the site. No other surface water bodies are present in the vicinity of the site.

1.4.1 GeologyThe facility is underlain stratigraphically by glacial, glaciofluvial, and glacial lacustrine sediments. Nearest the ground surface, varying thicknesses of fill associated with plant construction are present. Based on the regional geology, underlying the fill is approximately 15 feet of alluvial material deposited by Ship Creek (META 1994). The Bootlegger Cove Formation, made up of predominately silty clays and clayey silts, immediately underlies the alluvial sand and clay. This formation is estimated to be approximately 160 feet thick based on well logs. During excavations for this project, the soils in the immediate excavation areas were observed to be fairly uniform, consisting of well-graded gravels and sand mixtures with little fines. Occasional silt lenses were present. Semi-rounded coarse gravel and small cobbles were common, with a diameter up to 4 inches.

1.4.2 HydrogeologyGroundwater at the site consists of a shallow water table aquifer and a deep confined aquifer. The aquifers are separated by the fine-grained Bootlegger Cove Formation which has a low permeability and acts as an aquitard, or confining unit. The shallow unconfined aquifer underlies the entire site and ranges from 4 to 20 feet below ground surface (bgs). The shallow aquifer is



recharged primarily by precipitation and groundwater flow from areas upgradient from the site. Groundwater in this shallow aquifer discharges to Ship Creek and seeps, and also discharges by evapotranspiration. The general groundwater flow direction is west toward Cook Inlet (The RETEC Group 2008). Shallow groundwater measurements from monitoring wells 2A1, B-1 and B-3 (Figure 1-2) by HCG on October 8, 2009 found the depth to groundwater ranged from 4.01 to 5.71 feet bgs (report pending). The groundwater elevation data from this monitoring event and others indicate the groundwater flow direction is to the west, parallel to Ship Creek (see Figure1-2). The estimated hydraulic conductivity is anticipated to be in the range for coarse sand and gravel, 3.29x10-4 to 3.29x10-2 ft/s (Freeze and Cherry 1979). However, the numerous utilities and structures installed in the subsurface at the facility and the associated fill may have local effects on both groundwater flow direction and velocity. A web search was conducted using the Alaska Department of Natural Resources Well Log Tracking System (WELTS) to determine water supply wells located within 0.75 miles of the site. Several deep water supply wells, installed by the MOA and located near Merrill Field, were identified. Merrill Field is approximately 0.75 miles southwest and hydraulically upgradient from the site. No shallow water supply wells were positively identified in the shallow aquifer within 0.75 miles of the site. Several wells on the north side of Ship Creek were identified; however, these wells are on the opposite side of a hydrologic boundary (Ship Creek) and are not hydrologically connected to the site.

1.4.3 Land UseThe area in the vicinity of the Operations Building and the lowland area along Ship Creek have historically been, and will likely continue to be used for commercial and industrial purposes. The area is zoned for heavy or light industry, and the area immediately adjacent to the UST site, and most of the surrounding area, is covered by buildings, concrete, asphalt, and gravel fill. The site is fully developed and there is little remaining natural habitat.



2 UST RELEASE, REMOVAL AND CORRECTIVE ACTIONS

2.1 Initial Reported Release and Actions (Water Line Excavation) As stated in Section 1.1, on August 31, 2009, a dark fuel oil-like fluid was observed flowing into an excavation on top of the water table next to the Operations Building during a construction project to install water lines. The area is referred to as the Water Line Excavation on Figure 2-1. Photos of the excavation are provided in Appendix A, Photograph Log. The excavation was approximately 6 to 7 feet deep and extended below the water table. The water table had been temporarily lowered by pumping to support the excavation activities, and the oil-like product was not observed until this dewatering occurred. A review of old facility drawings identified the inactive UST as the most likely source of the product. Upon discovery of the suspected fuel release, oily water in the excavation was pumped into a vacuum truck for offsite disposal. Soil suspected of being contaminated was also removed from the lower portion of the excavation and placed on a lined containment. An oil-water separator system was installed to enable dewatering to continue and completion of the construction project. Dewatering was performed by installing a slotted culvert vertically as a sump next to the UST and pumping water to the surface for treatment and discharge. Water was run through an oil-water separator, and discharged to a secondary treatment tank where any remaining sheen was removed with sorbent pads. Treated water was discharged to the municipality’s sewer system in accordance with ML&Ps discharge permit. A Cleanup Plan was submitted by ML&P and approved by ADEC for site characterization and soil management during the remainder of the construction project (HCG 2009b). On September 4, the base of the excavation was expanded slightly to remove soil along the base of the excavation that may have become contaminated from contact with infiltrating product. The excavated soil was stockpiled on a liner. Three stockpiles of potentially contaminated soil were generated during the Water Line excavation, with a total volume of 11 yd3. Based on sample results, the stockpiled soil was either disposed offsite or determined to be suitable for onsite reuse (see Section 3.1.2). After soil removal was complete, soil samples for laboratory analysis were collected along the excavation bottom and sidewalls to characterize the site conditions prior to backfilling. Sample results are discussed in Section 3. Following sampling, the water lines were installed, the excavation was backfilled, and the project was completed. Backfill material consisted of clean fill from offsite; sewer rock was used to backfill the excavation to approximately 4 feet bgs, and gravel was used above the sewer rock.

2.2 UST Removal Following a review of old facility drawings, the likely source of the product was attributed to be the inactive UST. On September 1, 2009, the UST was emptied of approximately 425 gallons of fuel and 1,475 gallons of water. The fluids were sampled for the purpose of waste characterization and sent to an offsite Treatment, Storage and Disposal Facility (TSDF), Emerald Services in Anchorage, AK.



The UST was subsequently removed on September 14, 2009. A release investigation was conducted concurrently with the removal action, as a release was suspected. The removal action and release investigation were conducted in accordance with a project Work Plan (HCG 2009c) approved by ADEC. Photos of the UST removal and excavation are provided in Appendix A, Photograph Log. For reference, Appendix C includes the ADEC Site Assessment and Release Investigation Summary Form and ADEC UST Post Closure Notice, summarizing information included in this report. During the removal action, ground water dewatering continued because the UST removal required excavation below the water table. Initially, the upper 3 feet of soil, stockpile SP04, was removed from around the UST and placed on the adjacent asphalt (see Table 3-2). A concrete vault and cover, located directly on top of the UST, was removed. Dark staining was evident on the top surface of the concrete, especially in the vault area. The concrete was placed on a liner for eventual cleaning and testing. After the concrete cover was removed, soil around the sides of the UST was excavated. Soil excavated below 3 feet bgs (stockpile SP05) was placed on a liner pending the results of sampling and analysis. An excavation depth of approximately 6 feet bgs was required to remove the UST. The steel tank was approximately 11 feet long and 6 feet 2 inches in diameter with an estimated capacity of approximately 2,500 gallons. There were numerous (40-60) holes up to one inch in diameter along the lower half of the tank, estimated to be at the approximate water table level prior to dewatering. Fluids, primarily water with a small quantity of fuel, were still present in the UST on the date of its removal, and were pumped from the tank prior to the final excavation. Water in the tank was likely ground water that had infiltrated the tank through the numerous holes since the previous pumping on September 1. The oily water (508 gallons total) was sent to an offsite TSDF for disposal (Emerald Services, Anchorage, AK). After the UST was removed, visible product and sheening was present on groundwater at the bottom of the excavation. Product was removed with sorbent boom and pads. The most visibly-contaminated soils around the base and edges of the excavation were removed and combined with SP05 stockpiled soil. Following excavation, soil sampling was conducted along the perimeter of the excavation on all four sidewalls at multiple depth intervals to characterize the site conditions. The sample results are presented in Section 3. The excavation was backfilled after the completion of soil sampling. Backfill material consisted of three types: (1) From the bottom of the excavation to the estimated water table depth (4 feet bgs), backfill material consisted of approximately 40 yd3 of clean sewer rock (coarse gravel with no sand or fines); (2) Stockpile SP04 soil was placed over the sewer rock to a depth of 0.5 to 1 foot bgs. The SP004 soil (approximately 60 yd3) was originally removed from the upper 3 feet of soil within the excavation; (3) Approximately 12 yd3 of surface soil (0-3 bgs) from the Water Line excavation area was used to fill the remainder of the UST excavation. The area was paved approximately one week later. A cross section of the backfilled excavation is shown on Figure 2-2.



The UST was cleaned to remove any residual product and sent to Alaska Metal Recycling for disposal. The cleaning generated two 55-gallon drums of oily sludge. Nineteen drums of oily sorbent pads and boom were generated during cleanup activities at the Water Line and UST excavation. The drums, including the oily sludge, were sent to an offsite TSDF for disposal (Emerald Services, Anchorage, AK) with ultimate disposal in the lower 48 States. These wastes were characterized based on the product sample recovered from the UST (see Section 3.1). Groundwater pumping and treatment, as described in Section 2.1.1, was continued until September 21 to remove as much residual product as possible from soil and groundwater at the site. At the conclusion of groundwater treatment, no sheening was observed and no product was recovered in the oil-water separator over a 3-day period (Matthews 2009, pers. com.).

2.3 Sampling and Analysis Samples of soil, water and fuel product were collected for the purposes of site and waste characterization throughout the project using standardized methods according to the project Work Plans (HCG 2009b and 2009c) and ADEC guidance documents (ADEC 2002). Sampling was performed by HCG environmental scientists (Brent Veltkamp and Bret Berglund). All site characterization and most waste characterization samples were analyzed by SGS Environmental Services, Inc. in Anchorage, Alaska. Several waste characterization samples were analyzed by Columbia Analytical Services (CAS) in Kelso, Washington. Specific analyses for each sample type are detailed on tables 3-1 through 3-4 in Section 3. Site characterization samples were soil grab samples collected from discrete depth intervals in excavations and from soil stockpiles. Soil samples were collected by hand using clean disposable stainless steel sampling spoons, while wearing disposable nitrile sampling gloves. Soil collected for field duplicates for semi-volatiles analysis was homogenized in a decontaminated stainless steel bowl prior to filling sample jars. To aid in sample location selection, soil stockpiles were screened for volatiles using the headspace method as described in the ADEC UST Procedures Manual, Section 4.4.2 (ADEC 2002). Using this procedure, a photoionization detector (PID) headspace sample was collected and screened at a rate of at least one sample per 10 yd3. Samples were randomly distributed throughout the stockpile and collected at a depth of at least 18 inches below the surface. The screening locations and results were recorded in a field log book, and on stockpile screening logs. For soils contaminated or potentially contaminated, analytical samples were collected from the locations with the highest PID reading at a rate of at least two samples for the first 50 yd3 and 1 per every additional 50 yd3 (or portion thereof). The analyses were focused on the contaminants of concern based on the site history and results of the product sample from the UST (see Table 3-1), and included petroleum hydrocarbons (diesel range organics/residual range organics [DRO/RRO] and gasoline range organics/benzene, toluene, ethylbenzene, and total xylenes [GRO/BTEX]) and PCBs. Petroleum hydrocarbons were not analyzed if it was decided beforehand that stockpiled soil would be sent offsite for disposal based on PID-screening and visual observations. In stockpile SP04, consisting of cover soil from the UST excavation, PID readings were all less than 25 parts per million (ppm) and the soil was classified as clean and reused as excavation backfill without laboratory analysis.



Soil descriptions, field observations, PID results, and sample information was documented in the field logbook. Soil sample locations were documented by swing tying measurements from fixed reference points (buildings). Soils were classified using the Unified Soil Classification System (USCS) and recording observations of color, odor, and staining. Observations, descriptions, and other pertinent sample information were recorded in the field notebook.

2.4 Data Reporting Analytical data was provided in Level II hardcopy and electronic format. Lab reports are included on CD in Appendix D, along with a Data Quality Assessment and ADEC Laboratory Data Review Checklists. A Data Quality Assessment was performed in accordance with ADEC quality assurance procedures for laboratory data (ADEC 2009) to ensure that the data set met project data quality objectives. An ADEC Laboratory Data Review Checklist was completed for each laboratory work order. The data assessment did not include samples collected for waste characterization. The data review included an evaluation of the following and did not indicate any concerns limiting the usefulness of the data:

� chain-of-custody forms (CoCs), custody seals on coolers, and internal cooler arrival temperatures to ensure that the samples were securely transported and properly preserved;

� hold times (not applicable to PCBs);

� trip blanks;

� continuous calibration verifications;

� instrument and method/extraction and blanks;

� surrogate recoveries;

� laboratory control sample and laboratory control sample duplicate recovery (as percent recovery) and precision (as relative percent difference);

� matrix spike and matrix spike duplicate recovery (as percent recovery) and precision (as relative percent difference); and

� laboratory detection and reporting limits.

The data review indicated the reported laboratory data was of good quality. The following tabulated data qualifiers were added to the laboratory-provided data where applicable based on the evaluation.



Qualifier Description

FThe analyte was positively identified but the associated concentration was estimated above the method detection limit (MDL) and below the practical quantitation limit (PQL).

JThe analyte was positively identified, the quantitation was an estimate. Where applicable a “+” or “-” was appended to indicate positive or negative bias, respectively.

ND The analyte was analyzed for, but not detected. The associated numerical value was at or below the MDL.

M A matrix effect was present. Where applicable a “+” or “-” was appended to indicate positive or negative bias, respectively.

BThe compound was positively identified in the method blank and/or trip blank. The reported concentration was less than 5X that of the blank, or less than 10X for common laboratory contaminants, methylene chloride and acetone.

The rationale for applying qualifiers to specific data sets is described in the Data Quality Assessment. There were several volatile analytes identified where the MDL were higher than migration to groundwater cleanup levels. The MDLs reported with the data are typical for the methodology applied. For those analytes, it is not possible to state with certainty that the affected analytes are not present in the samples above migration to groundwater cleanup levels. The data set was 100% complete with no omissions or rejections with respect to analysis.



3 SAMPLE RESULTS

3.1 Waste Characterization Results The types and results of waste characterization samples are listed in Table 3-1, with the exception of soil stockpile sample results, listed on Table 3-2. Sample result tables are included at the end of this section. In addition to sample results, the tables also summarize the disposition of the various wastes. A description of the most relevant results is presented below. Analytical data reports are included in Appendix D (on CD).

3.1.1 Product and Water Samples A sample of the product removed from the UST was collected for laboratory analysis of oil burn specifications (total halogens, PCBs, Resource Conservation and Recovery Act [RCRA] metals, and flash point) and volatile organic compounds (VOCs). In addition, a product sample was collected from the Water Line Excavation in the sump area within building. The product results met the RCRA oil burn specification, except for PCBs (Table 3-1). PCBs were detected at 3.4 mg/Kg in the sample from the UST (PS03) and 17 mg/Kg in the product sample from the Water Line excavation (PS02). Based on the oil burn specifications results and visual observations, the product had the characteristics of a light fuel oil or diesel fuel. Chlorinated solvents were not present based on total halogen and VOC analysis. CAS also performed testing on product sample PS03 from the UST in order to provide additional information regarding the nature of the fuel. The testing included a hydrocarbon identification screen, specific gravity (0.85), and viscosity (2.90 centipoise [cP] @ 24.8 ºC). Based on the results, the laboratory concluded that the sample was composed primarily of an unknown slightly weathered diesel, potentially with some lighter fuels (Appendix D, CAS K0909082). A sample of the water recovered from the excavation was also analyzed for VOCs. (Table 3-1, Sample Water 1). No chlorinated solvents were detected, although some fuel components were present in low concentrations (less than 18 AAC 75.345, Table C, Groundwater Cleanup Levels).

3.1.2 Soil Stockpile Results Water Line ExcavationThe soil stockpiles from the Water Line Excavation (SP01, SP02 and SP03) all contained detectable PCBs (Table 3-2). However, no samples exceeded the ADEC Method Two cleanup level of 1 mg/Kg. Based on the petroleum levels, the soil was either classified for onsite reuse or sent offsite for disposal as a non-hazardous waste. The stockpile results were consistent with results for sample ES02, a sample collected from the bottom of the excavation prior to conducting the final soil removal. This composite sample was collected for planning purposes, with the intention of characterizing the contaminated soil prior to its removal. The sample was analyzed for PCBs and VOCs. Chlorinated solvents were not detected in the soil; however, PCBs were detected at 0.165 mg/Kg (Table 3-1). UST Excavation



Two stockpiles were generated during the UST removal. The first stockpile, designated SP04, consisted of sandy gravel soil from approximately 0-3 feet bgs, above the top level of the UST. The stockpile was approximately 60 yd³, and was not visibly contaminated. Six PID headspace screening samples were collected from the stockpile; the maximum reading was 7.8 ppm. No analytical samples were collected. The stockpile was designated suitable for reuse based on PID readings and visual observations, and was ultimately used as backfill in the excavation (at the time, PCB contamination was not suspected). Soil removed from the deeper portion of the excavation, designated stockpile SP05, was visibly contaminated with petroleum hydrocarbons. Four PID headspace screening samples were collected, all had elevated readings over the range of the instrument (>15,000). Laboratory analysis detected PCBs up to 114 mg/kg and DRO to 2,550 mg/Kg. The PCB concentration in the stockpile exceeded the Toxic Substances Control Act (TSCA) regulatory level of 50 mg/Kg. This required the soil to be disposed offsite as a TSCA regulated waste in a RCRA hazardous waste landfill.

3.2 Site Characterization Results

3.2.1 Water Line Excavation Area The soil sample results from the completed Water Line Excavation are presented on Table 3-3 and Figure 2-1. Analytical data reports are included in Appendix D (on CD). Samples were collected prior to installation of the water line and backfill of the excavation. Ten samples and one replicate were collected in locations distributed along the bottom of the excavation and sidewalls. The samples were analyzed for GRO/BTEX, DRO/ RRO, and PCBs; two samples from the most likely areas of contamination were analyzed for VOCs. No sample concentrations exceeded the ADEC Method Two cleanup level for the under 40-inch zone. However, DRO and two chlorinated solvents (tetrachloroethene and trichloroethene) exceeded the most stringent ADEC Method Two cleanup level (Migration to Groundwater). DRO exceeded this cleanup level in two locations along the floor of the excavation. The highest concentration (2,140 mg/Kg) was detected within a small excavation within the building (Sample ES07-6.5). This is the same location were the two chlorinated solvents exceeded the Migration to Groundwater cleanup level. PCBs were detected in 5 of 10 samples but no sample concentrations exceeded the ADEC Method Two cleanup level of 1 mg/Kg. Aroclor 1260 was the only PCB detected.

3.2.2 UST Excavation Area After the UST and soil removal was complete, soil samples were collected from the excavation to characterize the remaining soils. Samples were collected from twelve locations on the perimeter sidewalls of the excavation; at the bottom (6.0-6.5 feet bgs) and 4 feet bgs along all four sidewalls, and at 0.5 and 1.5 feet bgs on the southern and western sidewalls (Figure 2-1). Soil samples could not be collected directly below the former tank due to the presence of groundwater in the excavation. The soil samples were analyzed primarily for GRO/BTEX, DRO/RRO and PCBs, with some additional selective analyses for polynuclear aromatic hydrocarbons (PAHs).



Soil sample results are presented in Table 3-4 and summarized on Figure 2-1. Analytical data reports are included in Appendix D (on CD). DRO and PCBs exceeded the ADEC Method Two cleanup level for the under 40-inch zone (direct contact or ingestion). DRO exceeded the cleanup standard in two locations with a maximum concentration of 17,700 mg/kg. The more stringent Migration to Groundwater Cleanup standard was exceeded in 6 of 12 locations. PCBs were detected in all 12 sample locations, and exceeded 1 mg/Kg in 8 of 12 locations. The maximum PCB concentration was 112 mg/Kg. Three of the 12 samples were above 50 mg/Kg. Aroclor 1260 was the only PCB detected. Several PAH compounds (1-Methylnaphthalene and 2-methylnaphalene) slightly exceeded the ADEC Method Two Migration to Groundwater cleanup standard. Petroleum contamination was generally highest at the deepest sample point on a given sidewall. Near surface samples (0.5 and 1.5 feet bgs) contained relatively low levels of petroleum contamination. This suggests there may have been minor spills at the surface (perhaps during tank filling), but the primary point of release was in the subsurface near the water table. The highest concentrations of DRO tended to be on the south and west portions of the excavation. This southwest corner is the down gradient edge of the excavation based on the general groundwater flow in the area (Figure 2-1). In addition, alteration of the normal groundwater flow direction during dewatering of the Water Line Excavation may have inadvertently contributed to contaminant migration in this area. With respect to PCBs, the sampling indicated that contamination was generally highest in the surface soil next to the Operations Building. However, there were also some fairly elevated PCB concentrations in the subsurface at 4 to 6 feet bgs. The detected concentrations tended to decrease to the north. It is assumed PCBs are also present in the soil in the 1 to 4 feet bgs depth range within the backfilled excavation. PCBs were detected in all four sidewall samples from 0.5 and 1.5 feet bgs. Therefore, it is probable that the surface soil between these points contained PCBs. This surface soil was originally removed, and then placed back in the UST excavation at a depth of 1 to 4 feet bgs. Clean backfill was used below and above this material to fill the remainder of the excavation (see Section 2.2, and Figure 2-2).

3.3 Results Discussion A review of the data and site history suggests that there were probably two separate sources for the contaminants detected at the site.

� Spills/Leaks of diesel fuel from the UST, and � Spills/leaks of dielectric fluids with PCBs from the adjacent transformer.

The petroleum contamination at the site is attributed to leaks from the UST. The tank had numerous corrosion holes in its lower half indicating that leaks may have been occurring for some time. However, the current information indicates the release was relatively limited with respect to volume and area of impact. If there had been a long-term release consisting of multiple tank volumes, soils in the nearby Water Line excavation would likely have exhibited more extensive and higher concentrations of petroleum in the subsurface. In addition, it is likely the presence of a large, historical release would have been suspected or confirmed in the



groundwater sampling conducted as part of the Gasoline and Used Oil UST investigations in the 1990s (see Section 1.2). These sites and associated monitoring wells are located cross- or downgradient of the Operations Building UST. These circumstances suggest the leaks may have developed after the tank became inactive which limited the release to less than one tank volume. Assuming this is the case, the maximum volume of the release would be 1,975 gallons (original tank volume [2,500 gallons], minus recovered product [425 gallons], minus tank sludge [100 gallons]). In addition, there does not appear to have been significant migration in the direction of the Water Line Excavation until the groundwater in the area was artificially lowered by pumping in 2009. The most likely explanation for the presence of PCBs in the soil is a historical release or spill of dielectric fluids containing PCBs from the transformer originally located on the adjacent concrete pad. This release(s) likely occurred prior to 1974, when the transformer was replaced with a non-PCB containing transformer (see Section 1.1). The PCBs were most likely released at the ground surface and initially moved no farther than the immediate dielectric fluid spill area. PCBs have low water solubility, generally bind to fine grained soils, and do not migrate unless the soils are moved through human activity or natural processes (e.g., erosion). The presence of fuel leaking from the UST has probably contributed to the subsequent migration of PCBs from their initial point of release. PCBs are soluble in petroleum products such as fuel and oil, and can therefore be mobilized if light non-aqueous phase liquid (LNAPL) is present and migrating. These conditions were present in the vicinity of the UST and could account for the PCBs being detected in the subsurface at depths of 6 feet bgs. It could also account for the PCBs being detected at low concentrations (3.4 mg/Kg) in the fuel contained in the tank and in the product sampled from the Water Line Excavation. This appears to be more probable than the alternate explanation that fluids containing PCBs were disposed intentionally into the UST. The extent of PCB and petroleum hydrocarbon contamination in the soil or groundwater cannot be quantified with the available data set. However, as discussed above, the limited information available suggests impacts are relatively localized. Furthermore, the extent of PCB contamination should be limited to the extent of migration of the LNAPL phase (fuel or dielectric fluid), unless the PCBs were originally dispersed prior to the area being covered by asphalt. It is likely that petroleum and PCB-contaminated soil extends below the foundation of the Operations Building. On October 10, 2009, three monitoring wells downgradient of the UST excavation were sampled for DRO/RRO and PCBs (Figure 1-2, Wells 2A1, B-1 and B-2). When available, this data set will help define the extent of contaminant migration from the site, particularly dissolved components. A preliminary review of the data set indicates contaminants associated with the UST site have not caused elevated concentrations of contaminants at these locations (HCG 2009d).

Tabl

e 3-

1 Su

mm

ary

of W

aste

Cha

ract

eriz

atio

n Sa

mpl

esM

LP O

pera

tions

and

Dis

patc

h C

ente

r

Oth

er A

naly

ses

Ars

enic

Cad

miu

mC

hrom

ium

Lead

Lim

its:

37.8

°C

4,00

05

210

100

2N

A

PS

029/

1/20

09Li

quid

Pro

duct

col

lect

ed fr

om w

ater

line

ex

cava

tion,

sum

p ar

ea in

side

bu

ildin

g.

9324

6N

D (0

.4)

ND

(0.0

3)0.

2 F

ND

(0.4

)17

ND

(7.0

)R

ecov

ered

pro

duct

sen

t offs

ite to

TS

DF

(Em

eral

d S

ervi

ces)

PS

039/

1/20

09Li

quid

Pro

duct

sam

ple

from

US

T pr

ior t

o re

mov

al.

OB

S, V

OC

s61

ND

(100

)N

D (0

.4)

0.03

F0.

2 F

1.1

3.4

ND

(14)

Rec

over

ed p

rodu

ct s

ent o

ffsite

to T

SD

F (E

mer

ald

Ser

vice

s)

Wat

er1

9/1/

2009

Liqu

idO

ily w

ater

col

lect

ed fr

om v

acuu

m

truck

follo

win

g re

mov

al fr

om W

ater

Li

ne E

xcav

atio

n.

VO

Cs

NA

NA

NA

NA

NA

NA

NA

ND

(0.0

062)

3

Som

e fu

el c

ompo

unds

wer

e de

tect

ed

belo

w 1

8 A

AC

75

Tabl

e C

crit

eria

. S

ampl

e w

as ru

n at

a 2

0 fo

ld d

ilutio

n,

som

e M

DLs

are

ele

vate

d.

Oily

wat

er s

ent o

ffsite

to T

SD

F (E

mer

ald

Ser

vice

s)

Con

019/

17/2

009

Sol

id

(con

cret

e ch

ips)

Sam

ple

of c

oncr

ete

cove

r on

the

top

of U

ST.

Sam

ple

colle

cted

usi

ng

ham

mer

dril

l fro

m a

rea

of d

ark

stai

ning

on

conc

rete

insi

de s

urfa

ce o

f pi

ping

vau

lt af

ter t

ank

conc

rete

was

cl

eane

d.

PC

Bs

NA

NA

NA

NA

NA

NA

0.72

5N

A

Sam

ple

dept

h 0-

1.0

inch

es.

Con

cret

e w

as d

ark-

stai

ned

at th

e su

rface

, and

ligh

t gr

ey u

nder

neat

h su

rface

(uns

tain

ed).

Con

cret

e se

nt o

ffsite

for d

ispo

sal

(Anc

hora

ge R

egio

nal L

andf

ill).

Sta

ined

w

ood

arou

nd th

e va

ult w

as d

ispo

sed

with

so

il in

SP

05 (s

ee T

able

3-2

)

ES

029/

2/20

09S

olid

(s

oil)

Soi

l fro

m w

ater

line

exc

avat

ion.

R

epre

sent

ativ

e co

mpo

site

sam

ple

of

soil

that

was

to b

e ex

cava

ted

(col

lect

ed fr

om th

e co

ntam

inat

ed

zone

). P

urpo

se w

as to

exp

edite

w

aste

cha

ract

eriz

atio

n of

the

soil

for

disp

osal

.

PC

Bs,

VO

Cs

NA

NA

NA

NA

NA

NA

0.16

5N

D (0

.072

8)3

No

chlo

rinat

ed s

olve

nts

dete

cted

; som

e fu

el c

ompo

nent

s be

low

Met

hod

2 M

igra

tion

to G

roun

dwat

er.

Soi

l exc

avat

ed o

n 9/

4/20

09.

See

st

ockp

ile S

P03

, Tab

le 3

-2, S

oil S

tock

pile

Lo

g an

d S

ampl

e R

esul

tsN

otes

:1

- PC

B-1

260

was

the

cong

ener

det

ecte

d in

all

sam

ples

.2

- Sam

ples

wer

e an

alyz

ed fo

r Chl

oroe

than

e, V

inyl

Chl

orid

e, 1

-1-D

ichl

oroe

then

e, tr

ans-

1,2-

Dic

hlor

oeth

ene,

cis

-1,2

-Dic

hlor

oeth

ene,

1,2

-Dic

hlor

oeth

ane,

Tric

hlor

oeth

ene,

1,1

,2-T

richl

oroe

than

e,

T

etra

chlo

roet

hene

, 1,1

,2,2

-Tet

rach

loro

etha

ne.

For n

onde

tect

s ("

ND

"), t

he h

ighe

st m

etho

d de

tect

ion

limit

is s

how

n in

par

enth

eses

.3

- The

se s

ampl

es w

ere

anal

yzed

for f

ull l

ist v

olat

ile o

rgan

ic c

ompo

unds

. N

o ch

lorin

ated

sol

vent

s w

ere

dete

cted

. S

cree

ning

Crit

eria

are

18

AA

C 7

5 Ta

ble

C fo

r wat

ers

and

Tabl

es B

1 an

d B

2 fo

r soi

ls.

T

here

fore

, the

se w

aste

s w

ere

assu

med

to h

ave

PC

Bs

< 50

mg/

Kg.

Dat

a Fl

ags

Fre

porte

d va

lue

was

bet

wee

n th

e la

bora

tory

MD

L an

d P

QL

ND

nond

etec

t, m

etho

d de

tect

ion

limit

is p

rese

nted

in b

rack

ets

to th

e le

ft

Abb

revi

atio

nsA

AC

Ala

ska

Adm

inis

trativ

e C

ode

PC

BP

olyc

hlor

inat

ed B

iphe

nyl

MD

LM

etho

d D

etec

tion

Lim

itP

QL

Pra

ctic

al Q

uant

itatio

n Li

mit

mg/

Kg

mill

igra

ms

per k

ilogr

amTS

DF

Trea

tmen

t, S

tora

ge, a

nd D

ispo

sal F

acili

tyN

AN

ot A

naly

zed

VO

CV

olat

ile O

rgan

ic C

ompo

und

OB

SO

il B

urni

ng S

peci

ficat

ion

Bol

d an

d Sh

aded

= S

ampl

e re

sults

exc

eed

the

scre

enin

g cr

iteria

.

4- T

he p

rodu

ct s

ampl

es (P

S02

and

PS

03) w

ere

also

use

d to

cha

ract

eriz

e th

e 2

drum

s of

oil

slud

ge, a

nd 1

9 dr

ums

of o

iled

sorb

ent p

ads,

boo

m, a

nd P

PE

gen

erat

ed d

urin

g th

e cl

eanu

p.

Chl

orin

ated

Solv

ents

2

(mg/

L)

Com

men

ts a

nd D

ispo

sitio

n of

A

pplic

able

Was

te

OB

S, V

OC

s

Ana

lysi

sSa

mpl

e ID

Sam

ple

Dat

eSa

mpl

e Ty

peLo

catio

n/D

escr

iptio

n

Sum

mar

y of

Ana

lytic

al R

esul

tsO

il B

urn

Spec

ifica

tions

(OB

S)

Met

als

(mg/

Kg)

Flas

hPo

int

(°C

)

Tota

lH

alog

ens

(mg/

L)

PCB

s(m

g/K

g)1

3-5

Tabl

e 3-

2. S

oil S

tock

pile

Log

and

Sam

ple

Res

ults

MLP

Ope

ratio

ns a

nd D

ispa

tch

Cen

ter

PCB

sD

RO

RR

OG

RO

BTE

X

SP

01

Wat

er L

ine

Exc

avat

ion:

Firs

t soi

l fro

m p

oten

tially

-co

ntam

inat

ed s

oil r

emov

ed w

ith

vacu

um tr

uck

39/

1/20

099/

4/20

0995

in

-situ

SP

010.

0696

87.8

36.5

4.04

ND

[0.0

141]

No

cont

amin

ants

det

ecte

d ab

ove

regu

lato

ry c

lean

up le

vels

(AD

EC

or

TSC

A).

Soi

l is

stor

ed o

nsite

in th

e P

ole

Yar

d on

the

grou

nd s

urfa

ce.

In

2010

, soi

l will

be

used

for r

e-gr

adin

g no

rthw

est o

f the

Veh

icle

Mai

nten

ance

B

uild

ing

and

pave

d w

ith a

spha

lt.

AD

EC

not

ified

of p

lan

and

conc

urre

d in

S

ept.

2009

.

SP

025

9/1/

2009

9/4/

2009

1500

0+in

-situ

SP

02A

0.22

3N

AN

AN

AN

A

1500

0+in

-situ

SP

02B

0.38

0N

AN

AN

AN

A

SP

033

9/4/

2009

9/4/

2009

191

in-s

ituS

P03

A0.

121

NA

NA

NA

NA

337

in-s

ituS

P03

B0.

0619

NA

NA

NA

NA

SP

04U

ST

Exc

avat

ion:

su

rface

soi

l 0-3

' bgs

609/

11/2

009

9/14

/200

97.

8he

adsp

ace

Scr

eeni

ng

Onl

yN

AN

AN

AN

AN

AU

sed

to b

ackf

ill U

ST

exca

vatio

n fro

m

appr

oxim

atel

y 4.

0 to

0.7

feet

bgs

.

SP

0512

9/14

/200

99/

14/2

009

1500

0+he

adsp

ace

SP

05A

114

2550

351

NA

NA

1500

0+he

adsp

ace

SP

05B

94.1

2420

350

NA

NA

Not

es:

1) S

oil P

ID-s

cree

ned

from

mul

tiple

loca

tions

; are

a of

hig

hest

PID

read

ing

was

sam

pled

for l

abor

ator

y an

alys

is. P

ID re

adin

gs w

ere

both

in-s

itu, a

nd b

agge

d he

adsp

ace

read

ings

as

show

n.

2) S

oil f

rom

sto

ckpi

les

SP

02, S

P03

, and

SP

05 w

as s

ent o

ffsite

to E

mer

ald

Ser

vice

s (A

ncho

rage

AK

) and

then

to th

e lo

wer

48

Sta

tes

for d

ispo

sal.

S

oil w

ith P

CB

s >

50 m

g/K

g w

as d

ispo

sed

in a

RC

RA

haz

ardo

us w

aste

land

fill (

Sub

title

C la

ndfil

l).

The

othe

r soi

ls w

ere

disp

osed

in a

non

-haz

ardo

us w

aste

land

fill (

RC

RA

Sub

title

D).

3) P

CB

-126

0 w

as th

e co

ngen

er id

entif

ied.

Dat

a Fl

ags

ND

nond

etec

t, m

etho

d de

tect

ion

limit

is p

rese

nted

in b

rack

ets

to th

e le

ft

Abb

revi

atio

nsA

AC

Ala

ska

Adm

inis

trativ

e C

ode

NA

not a

naly

zed

AD

EC

Ala

ska

Dep

artm

ent o

f Env

ironm

enta

l Con

serv

atio

nP

CB

Pol

ychl

orin

ated

Bip

heny

lbg

sbe

low

gro

und

surfa

ceP

IDph

otoi

oniz

atio

n de

tect

orB

TEX

benz

ene,

tolu

ene,

eth

ylbe

nzen

e, a

nd to

tal x

ylen

esP

QL

Pra

ctic

al Q

uant

itatio

n Li

mit

DR

Odi

esel

rang

e or

gani

csR

CR

AR

esou

rce

Con

serv

atio

n an

d R

ecov

ery

Act

GR

Oga

solin

e ra

nge

orga

nics

RR

Ore

sidu

al ra

nge

orga

nics

MD

Lm

etho

d de

tect

ion

limit

TSC

ATo

xic

Sub

stan

ces

Con

trol A

ctm

g/K

gm

illig

ram

s pe

r kilo

gram

TSD

FTr

eatm

ent,

Sto

rage

and

Dis

posa

l Fac

ility

Stoc

kpile

N

umbe

rO

rigin

of S

oil

App

roxi

mat

e Si

ze o

f St

ockp

ile in

C

ubic

Yar

ds

Exca

vatio

n D

ate

US

T E

xcav

atio

n:so

ils 3

-6.5

' bgs

nex

t to

tank

Dis

posi

tion

of S

oil

Sen

t offs

ite fo

r dis

posa

l at T

SD

F2

Sen

t offs

ite fo

r dis

posa

l at T

SD

F2

Sen

t offs

ite fo

r dis

posa

l at T

SD

F

(TS

CA

regu

late

d w

aste

, P

CB

s>50

mg/

Kg)

2

Ana

lytic

al R

esul

ts (m

g/K

g)PI

D

Rea

ding

(p

pm)

Lab

Sam

ple

Num

ber

Wat

er L

ine

Exc

avat

ion:

Rem

oved

with

vac

uum

truc

k du

ring

final

exc

avat

ion

clea

nup

Sam

ple

Dat

e

Wat

er L

ine

Exc

avat

ion:

Sec

ond

batc

h of

soi

l rem

oved

fro

m m

ain

exca

vatio

n w

ith

vacu

um tr

uck

3-7

Tabl

e 3-

3. W

ater

Lin

e E

xcav

atio

n S

oil S

ampl

e R

esul

ts, S

epte

mbe

r 4, 2

009

(Pos

t Rem

oval

Act

ion)

MLP

Ope

ratio

ns a

nd D

ispa

tch

Cen

ter

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Con

cFl

agSample Dep

th(feet b

gs)

‐‐--

----

----

Fuel

s ( A

K10

2, A

K10

2, a

nd A

K10

3)

Gasoline Ra

nge Organics

1,40

030

0[1.3]

ND

[0.831

]ND

1.35

J[0.889

]ND

0.74

6J

7.06

=[0.873

]ND

[0.675

]ND

[0.832

]ND

[0.762

]ND

[0.803

]ND

[0.743

]N

D7.06

=3/

100/

10N

oDiesel Range Organics

10,2

5025

027

2=

9.85

J[6.96]

ND

[6.83]

ND

8.17

J2,14

0=

[6.76]

ND

15.3

J[6.68]

ND

37.8

J45

.3=

‐‐--

2,14

0=

7/10

0/10

No

Residu

al Range Organics

10,0

0010

,000

175

.2J

37.8

=[6.96]

ND

[6.83]

ND

[6.8]

ND

78.4

J9.55

J12

0=

44.3

=34

7=

7.4

J‐‐

--34

7=

8/10

0/10

No

Ben

zene

, Eth

ylbe

nzen

e, T

olue

ne, a

nd X

ylen

es (S

W80

21B

)Be

nzen

e11

0.02

5[0.006

94]

ND

[0.004

43]

ND

[0.005

47]

ND

[0.004

74]

ND

0.00

608

J[0.003

08]

ND

[0.004

65]

ND

[0.003

6]ND

[0.004

44]

ND

[0.004

07]

ND

[0.004

28]

ND

[0.003

96]

ND

0.00

608

J1/

100/

10N

oEthylben

zene

110

6.9

[0.026

]ND

[0.016

6]ND

[0.020

5]ND

[0.017

8]ND

[0.012

4]ND

0.01

25J

[0.017

5]ND

[0.013

5]ND

[0.016

6]ND

[0.015

2]ND

[0.016

1]ND

[0.014

9]N

D0.01

25J

1/10

0/10

No

Toluen

e22

06.5

[0.026

]ND

[0.016

6]ND

[0.020

5]ND

[0.017

8]ND

[0.012

4]ND

[0.011

5]ND

[0.017

5]ND

[0.013

5]ND

[0.016

6]ND

[0.015

2]ND

[0.016

1]ND

[0.014

9]N

D[0.026

]ND

0/10

0/10

No

o‐Xylene

--‐‐

[0.026

]ND

[0.016

6]ND

[0.020

5]ND

[0.017

8]ND

0.01

92J

0.15

6=

[0.017

5]ND

[0.013

5]ND

[0.016

6]ND

[0.015

2]ND

[0.016

1]ND

[0.014

9]N

D0.15

6=

2/10

0/10

No

P & M

‐Xylen

e--

--[0.026

]ND

[0.016

6]ND

[0.020

5]ND

[0.017

8]ND

0.02

18J

0.2

=[0.017

5]ND

[0.013

5]ND

[0.016

6]ND

[0.015

2]ND

[0.016

1]ND

[0.014

9]N

D0.2

=2/

100/

10N

oTo

tal Xylen

es63

63[0.026

]ND

[0.016

6]ND

[0.020

5]ND

[0.017

8]ND

0.04

1J

0.35

6=

[0.017

5]ND

[0.013

5]ND

[0.016

6]ND

[0.015

2]ND

[0.016

1]ND

[0.014

9]N

D0.35

6=

2/10

0/10

No

1,1,1,2‐Tetrachloroe

thane

----

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,1,1‐Trichloroe

thane

360

0.82

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,1,2,2‐Tetrachloroe

thane

5.5

0.01

7--

----

----

----

--[0.012

4]ND

[0.011

5]ND

----

----

----

----

----

----

[0.012

4]ND

0/2

0/2

No

1,1,2‐Trichloroe

thane

110.01

8--

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,1‐Dichloroe

thane

900

25--

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,1‐Dichloroe

then

e0.85

0.03

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,1‐Dichlorop

rope

ne--

----

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,2,3‐Trichlorob

enzene

----

----

----

----

----

[0.012

4]ND

[0.011

5]ND

----

----

----

----

----

----

[0.012

4]ND

0/2

0/2

No

1,2,3‐Trichlorop

ropane

0.17

0.00

053

----

----

----

----

[0.012

4]ND

[0.011

5]ND

----

----

----

----

----

----

[0.012

4]ND

0/2

0/2

No

1,2,4‐Trichlorob

enzene

410.85

----

----

----

----

[0.012

4]ND

[0.011

5]ND

----

----

----

----

----

----

[0.012

4]ND

0/2

0/2

No

1,2,4‐Trim

ethylben

zene

4923

----

----

----

----

[0.006

47]

ND

0.78

3=

----

----

----

----

----

----

0.78

3=

1/2

0/2

No

1,2‐Dibromo‐3‐chloroprop

ane

----

----

----

----

----

[0.025

7]ND

[0.023

8]ND

----

----

----

----

----

----

[0.025

7]ND

0/2

0/2

No

1,2‐Dibromoe

thane

0.6

0.00

016

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,2‐Dichlorob

enzene

455.1

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,2‐Dichloroe

thane

4.8

0.01

6--

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,2‐Dichlorop

ropane

5.3

0.01

8--

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,3,5‐Trim

ethylben

zene

4223

----

----

----

----

[0.006

47]

ND

0.21

1=

----

----

----

----

----

----

0.21

1=

1/2

0/2

No

1,3‐Dichlorob

enzene

6928

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,3‐Dichlorop

ropane

----

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

1,4‐Dichlorob

enzene

300.64

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

2,2‐Dichlorop

ropane

----

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

2‐Bu

tano

ne (M

EK)

23,300

59--

----

----

----

--[0.064

7]ND

[0.06]

ND

----

----

----

----

----

----

[0.064

7]ND

0/2

0/2

No

2‐Ch

lorotoluen

e--

----

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

2‐Hexanon

e--

----

----

----

----

--[0.064

7]ND

[0.06]

ND

----

----

----

----

----

----

[0.064

7]ND

0/2

0/2

No

4‐Ch

lorotoluen

e--

----

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

4‐Isop

ropylto

luen

e--

----

----

----

----

--[0.006

47]

ND

0.11

4=

----

----

----

----

----

----

0.11

4=

1/2

0/2

No

4‐Methyl‐2

‐pen

tano

ne (M

IBK)

8.1

----

----

----

----

[0.064

7]ND

[0.06]

ND

----

----

----

----

----

----

[0.064

7]ND

0/2

0/2

No

Benzen

e0.02

5--

----

----

----

--[0.004

15]

ND

[0.003

84]

ND

----

----

----

----

----

----

[0.004

15]

ND

0/2

0/2

No

Brom

oben

zene

----

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Brom

ochlorom

ethane

----

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Brom

odichlorom

ethane

100.04

4--

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Brom

oform

420

0.34

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Brom

omethane

140.16

----

----

----

----

[0.051

4]ND

[0.047

7]ND

----

----

----

----

----

----

[0.051

4]ND

0/2

0/2

No

Carbon

disulfid

e25

012

----

----

----

----

[0.025

7]ND

[0.023

8]ND

----

----

----

----

----

----

[0.025

7]ND

0/2

0/2

No

Carbon

tetrachloride

3.1

0.02

3--

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Chlorobe

nzen

e20

00.63

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Chloroethane

2358

0--

----

----

----

--[0.051

4]ND

[0.047

7]ND

----

----

----

----

----

----

[0.051

4]ND

0/2

0/2

No

Chloroform

3.2

0.46

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Chloromethane

250.21

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

cis‐1,2‐Dichloroe

then

e13

00.24

----

----

----

----

[0.006

47]

ND

0.04

31=

----

----

----

----

----

----

0.04

31=

1/2

0/2

No

cis‐1,3‐Dichlorop

rope

ne27

0.03

3--

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Dibromochlorom

ethane

140.03

2--

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Dibromom

ethane

370

1.1

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Dichlorod

ifluo

romethane

380

140

----

----

----

----

[0.012

4]ND

[0.011

5]ND

----

----

----

----

----

----

[0.012

4]ND

0/2

0/2

No

Ethylben

zene

110

6.9

----

----

----

----

[0.006

47]

ND

0.01

5J

----

----

----

----

----

----

0.01

5J

1/2

0/2

No

Hexachlorob

utadiene

3.8

0.12

----

----

----

----

[0.012

4]ND

[0.011

5]ND

----

----

----

----

----

----

[0.012

4]ND

0/2

0/2

No

Freq

uenc

y A

bove

Pr

imar

y Sc

reen

ing

Crit

eria

5,6

Con

tam

inan

t of

Con

cern

(C

OC

)7

ES05

‐2.5

04‐Sep

‐09

1094

6980

11

2.5

ES06

‐204

‐Sep

‐09

1094

6980

12

ES07

‐2.5

04‐Sep

‐09

1094

6980

13

‐‐

Sam

ple

Loca

tions

3

Max

imum

C

once

ntra

tion4

Freq

uenc

y of

D

etec

tion5

2.5

2

ES06

‐5.5

04‐Sep

‐09

1094

6980

06

ES07

‐6.5

04‐Sep

‐09

1094

6980

08

6.5

ES03

‐2.5

04‐Sep

‐09

1094

6980

09

ES04

‐2.5

04‐Sep

‐09

1094

6980

10

2.5

2.5

Trip Blank

04‐Sep

‐09

1094

6980

19

ES03

‐704

‐Sep

‐09

1094

6980

01

ES04

‐6.5

04‐Sep

‐09

1094

6980

02

76.5

6

Prim

ary

ES05

‐604

‐Sep

‐09

1094

6980

03

65.5

Replicate

ES09

5‐6

04‐Sep

‐09

1094

6980

07

Vola

tile

Org

anic

Com

poun

ds (S

W82

60B

)

Met

hod

Two

(und

er 4

0-in

ch

zone

)1

Met

hod

Two

Mig

ratio

n to

G

roun

dwat

er2

Compo

und:

milligrams pe

r kilogram

(mg/Kg

)

3-9

UST

Rel

ease

Inve

stig

atio

n Re

port

M

L&P

Ope

ratio

ns a

nd D

ispa

tch

Cen

ter

Prep

ared

for M

unic

ipal

Lig

ht &

Pow

er

1-

7

N

ovem

ber 2

009

This

pag

e in

tent

iona

lly le

ft bl

ank.

sheiges

Text Box

3-10

Tabl

e 3-

3. W

ater

Lin

e E

xcav

atio

n S

oil S

ampl

e R

esul

ts, S

epte

mbe

r 4, 2

009

(Pos

t Rem

oval

Act

ion)

MLP

Ope

ratio

ns a

nd D

ispa

tch

Cen

ter

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Conc

Flag

Con

cFl

agSample Dep

th(feet b

gs)

‐‐--

----

----

Freq

uenc

y A

bove

Pr

imar

y Sc

reen

ing

Crit

eria

5,6

Con

tam

inan

t of

Con

cern

(C

OC

)7

ES05

‐2.5

04‐Sep

‐09

1094

6980

11

2.5

ES06

‐204

‐Sep

‐09

1094

6980

12

ES07

‐2.5

04‐Sep

‐09

1094

6980

13

‐‐

Sam

ple

Loca

tions

3

Max

imum

C

once

ntra

tion4

Freq

uenc

y of

D

etec

tion5

2.5

2

ES06

‐5.5

04‐Sep

‐09

1094

6980

06

ES07

‐6.5

04‐Sep

‐09

1094

6980

08

6.5

ES03

‐2.5

04‐Sep

‐09

1094

6980

09

ES04

‐2.5

04‐Sep

‐09

1094

6980

10

2.5

2.5

Trip Blank

04‐Sep

‐09

1094

6980

19

ES03

‐704

‐Sep

‐09

1094

6980

01

ES04

‐6.5

04‐Sep

‐09

1094

6980

02

76.5

6

Prim

ary

ES05

‐604

‐Sep

‐09

1094

6980

03

65.5

Replicate

ES09

5‐6

04‐Sep

‐09

1094

6980

07

Met

hod

Two

(und

er 4

0-in

ch

zone

)1

Met

hod

Two

Mig

ratio

n to

G

roun

dwat

er2

Compo

und:

milligrams pe

r kilogram

(mg/Kg

)

Isop

ropylben

zene

(Cum

ene)

6251

----

----

----

----

[0.006

47]

ND

0.02

56=

----

----

----

----

----

----

0.02

56=

1/2

0/2

No

Methylene

chloride

160

0.01

6--

----

----

----

--[0.025

7]ND

[0.023

8]ND

----

----

----

----

----

----

[0.025

7]ND

0/2

0/2

No

Methyl‐t‐butyl ether

290

1.3

----

----

----

----

[0.009

96]

ND

[0.009

23]

ND

----

----

----

----

----

----

[0.009

96]

ND

0/2

0/2

No

Naphthalene

2820

----

----

----

----

0.02

09J

3.9

=--

----

----

----

----

----

--3.9

=2/

20/

2N

on‐Bu

tylben

zene

4215

----

----

----

----

0.00

726

J0.17

8=

----

----

----

----

----

----

0.17

8=

2/2

0/2

No

n‐Prop

ylbe

nzen

e42

15--

----

----

----

--0.01

04J

0.03

88=

----

----

----

----

----

----

0.03

88=

2/2

0/2

No

o‐Xylene

----

----

----

----

----

[0.012

4]ND

0.12

4=

----

----

----

----

----

----

0.12

4=

1/2

0/2

No

P & M

‐Xylen

e--

----

----

----

----

--[0.012

4]ND

0.22

2=

----

----

----

----

----

----

0.22

2=

1/2

0/2

No

sec‐Bu

tylben

zene

4112

----

----

----

----

[0.006

47]

ND

0.07

27=

----

----

----

----

----

----

0.07

27=

1/2

0/2

No

Styren

e20

00.96

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

tert‐Butylbe

nzen

e70

12--

----

----

----

--[0.006

47]

ND

0.00

673

J--

----

----

----

----

----

--0.00

673

J1/

20/

2N

oTetrachloroe

then

e10

0.02

4--

----

----

----

--[0.006

47]

ND

0.03

09=

----

----

----

----

----

----

0.03

09=

1/2

0/2

No

Toluen

e22

06.5

----

----

----

----

[0.012

4]ND

[0.011

5]ND

----

----

----

----

----

----

[0.012

4]ND

0/2

0/2

No

trans‐1,2‐Dichloroe

then

e16

00.37

----

----

----

----

[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

trans‐1,3‐Dichlorop

rope

ne27

0.03

3--

----

----

----

--[0.006

47]

ND

[0.006

]ND

----

----

----

----

----

----

[0.006

47]

ND

0/2

0/2

No

Trichloroe

then

e0.57

0.02

----

----

----

----

[0.006

47]

ND

0.07

38=

----

----

----

----

----

----

0.07

38=

1/2

0/2

No

Trichlorofluorom

ethane

990

86--

----

----

----

--[0.012

4]ND

[0.011

5]ND

----

----

----

----

----

----

[0.012

4]ND

0/2

0/2

No

Vinyl chloride

4.3

0.00

85--

----

----

----

--[0.009

96]

ND

[0.009

23]

ND

----

----

----

----

----

----

[0.009

96]

ND

0/2

0/2

No

Xylene

s (total)

6363

----

----

----

----

[0.024

9]ND

0.34

6=

----

----

----

----

----

----

0.34

6=

1/2

0/2

No

Aroclor‐101

6--

--[0.016

8]ND

[0.016

3]ND

[0.016

8]ND

[0.016

5]ND

[0.016

5]ND

[0.016

]ND

[0.016

3]ND

[0.016

]ND

[0.016

2]ND

[0.016

]ND

[0.015

3]ND

‐‐--

[0.016

8]ND

0/10

0/10

No

Aroclor‐122

1--

--[0.016

8]ND

[0.016

3]ND

[0.016

8]ND

[0.016

5]ND

[0.016

5]ND

[0.016

]ND

[0.016

3]ND

[0.016

]ND

[0.016

2]ND

[0.016

]ND

[0.015

3]ND

‐‐--

[0.016

8]ND

0/10

0/10

No

Aroclor‐123

2--

--[0.016

8]ND

[0.016

3]ND

[0.016

8]ND

[0.016

5]ND

[0.016

5]ND

[0.016

]ND

[0.016

3]ND

[0.016

]ND

[0.016

2]ND

[0.016

]ND

[0.015

3]ND

‐‐--

[0.016

8]ND

0/10

0/10

No

Aroclor‐124

2--

--[0.016

8]ND

[0.016

3]ND

[0.016

8]ND

[0.016

5]ND

[0.016

5]ND

[0.016

]ND

[0.016

3]ND

[0.016

]ND

[0.016

2]ND

[0.016

]ND

[0.015

3]ND

‐‐--

[0.016

8]ND

0/10

0/10

No

Aroclor‐124

8--

--[0.016

8]ND

[0.016

3]ND

[0.016

8]ND

[0.016

5]ND

[0.016

5]ND

[0.016

]ND

[0.016

3]ND

[0.016

]ND

[0.016

2]ND

[0.016

]ND

[0.015

3]ND

‐‐--

[0.016

8]ND

0/10

0/10

No

Aroclor‐125

4--

--[0.016

8]ND

[0.016

3]ND

[0.016

8]ND

[0.016

5]ND

[0.016

5]ND

[0.016

]ND

[0.016

3]ND

[0.016

]ND

[0.016

2]ND

[0.016

]ND

[0.015

3]ND

‐‐--

[0.016

8]ND

0/10

0/10

No

Aroclor‐126

0--

--0.28

2=

[0.016

3]ND

[0.016

8]ND

[0.016

5]ND

[0.016

5]ND

0.42

7=

[0.016

3]ND

0.49

2=

0.06

96=

0.44

5=

[0.015

3]ND

‐‐--

0.49

2=

5/10

0/10

No

Total PCB

s1.

01.

00.28

2=

[0.016

3]ND

[0.016

8]ND

[0.016

5]ND

[0.016

5]ND

0.42

7=

[0.016

3]ND

0.49

2=

0.06

96=

0.44

5=

[0.015

3]ND

‐‐--

0.49

2=

5/10

0/10

No

Perc

ent S

olid

s (S

M25

40G

)To

tal Solids

----

89=

90.1

=88

.9=

90.4

=90

.9=

92.6

=90

.7=

93.2

=91

.9=

92.2

=96

.8=

‐‐--

----

----

--N

otes

:1

- Prim

ary

Scr

eeni

ng C

riter

ia:

the

clea

nup

leve

l cor

resp

onds

to th

e lo

wes

t val

ue fo

r dire

ct c

onta

ct o

r inh

alat

ion

of s

oil a

s lis

ted

in 1

8 A

AC

75.

341,

Tab

les

B1

and

B2,

(Met

hod

Two

clea

nup

leve

ls) f

or th

e un

der 4

0 in

ch z

one

(Oct

ober

9, 2

008)

. 2

- Sec

onda

ry S

cree

ning

Crit

eria

: th

e va

lue

corr

espo

nds

to th

e va

lue

liste

d in

18

AA

C 7

5.34

1, T

able

s B

1 an

d B

2, M

igra

tion

to G

roun

dwat

er (O

ctob

er 9

, 200

8).

3 - T

he fi

eld

sam

ple

iden

tific

atio

n nu

mbe

r, da

te c

olle

cted

and

labo

rato

ry s

ampl

e id

entif

icat

ion

num

ber a

re p

rovi

ded.

The

sam

ple

dept

h in

feet

is li

sted

afte

r the

hyp

hen

at th

e en

d of

the

sam

ple

iden

tific

atio

n nu

mbe

r.4

- The

max

imum

con

cent

ratio

n of

a d

etec

ted

anal

yte

is s

how

n. I

f an

anal

yte

was

not

det

ecte

d, th

en th

e hi

ghes

t MD

L is

sho

wn.

Trip

bla

nks

are

not i

nclu

ded.

5 - A

par

ent a

nd d

uplic

ate

sam

ple

are

coun

ted

as o

ne s

ampl

e. T

he h

ighe

r of t

he tw

o va

lues

are

use

d fo

r the

pur

pose

of c

ount

ing

dete

ctio

ns a

nd e

xcee

danc

es.

Trip

bla

nks

are

not i

nclu

ded.

6 - S

cree

ning

crit

eria

val

ues

are

from

18

AA

C 7

5.34

1 M

etho

d Tw

o U

nder

40-

inch

Zon

e. T

otal

val

ues

are

the

sum

mat

ion

of d

etec

ted

com

poun

ds o

nly.

If a

ll va

lues

are

non

dete

ctab

le, t

he h

ighe

st M

DL

is s

how

n.7

- A c

ompo

und

is c

onsi

dere

d a

CO

C if

it e

xcee

ds th

e pr

imar

y sc

reen

ing

crite

ria.

8 - T

otal

val

ues

wer

e th

e su

mm

atio

n of

det

ecte

d co

mpo

unds

onl

y. I

f com

poun

ds w

ere

not d

etec

ted,

then

the

high

est M

DL

was

list

ed.

Dat

a Fl

ags

ND

nond

etec

t, m

etho

d de

tect

ion

limit

is p

rese

nted

in b

rack

ets

to th

e le

ftJ

estim

ated

val

ue, a

"+" o

r "-"

indi

cate

s a

posi

tive

or n

egat

ive

bias

Fre

porte

d va

lue

was

bet

wee

n th

e la

bora

tory

MD

L an

d P

QL

=A

det

ecte

d co

mpo

und

(con

cent

ratio

n lis

ted

in c

olum

n to

the

left)

Bco

mpo

und

was

det

ecte

d in

the

met

hod

blan

k or

trip

bla

nk

Abb

revi

atio

ns--

Not

app

licab

le o

r scr

eeni

ng c

riter

ia d

oes

not e

xist

for t

his

com

poun

dm

g/K

gm

illig

ram

s pe

r kilo

gram

AA

CA

lask

a A

dmin

istra

tive

Cod

eP

CB

Pol

ychl

orin

ated

Bip

heny

lbg

sbe

low

gro

und

surfa

ceP

QL

Pra

ctic

al Q

uant

itatio

n Li

mit

CO

CC

onta

min

ant o

f Con

cern

MD

LM

etho

d D

etec

tion

Lim

it

bold

and

sha

ded

- val

ue e

xcee

ds p

rimar

y sc

reen

ing

crite

ria (M

etho

d Tw

o C

lean

up L

evel

s)sh

aded

- va

lue

exce

eds

Met

hod

Two

mig

ratio

n to

gro

undw

ater

cle

anup

leve

ls.

Poly

chlo

rinat

ed B

iphe

nyls

(SW

8082

)

3-9

sheiges

Text Box

3-11

UST

Rel

ease

Inve

stig

atio

n Re

port

M

L&P

Ope

ratio

ns a

nd D

ispa

tch

Cen

ter

Prep

ared

for M

unic

ipal

Lig

ht &

Pow

er

1-

7

N

ovem

ber 2

009

This

pag

e in

tent

iona

lly le

ft bl

ank.

sheiges

Text Box

3-12

Tabl

e 3-

4. U

ST

Exc

avat

ion

Soi

l Sam

ple

Res

ults

, Sep

tem

ber 1

4, 2

009

(Pos

t Rem

oval

Act

ion)

MLP

Ope

ratio

ns a

nd D

ispa

tch

Cen

ter

Con

cFl

agC

onc

Flag

Con

cFl

agC

onc

Flag

Con

cFl

agC

onc

Flag

Con

cFl

agC

onc

Fla g

Con

cFl

agC

onc

Flag

Con

cFl

agC

onc

Flag

Con

cFl

agC

onc

Flag

Con

cFl

agC

onc

Flag

Sam

ple

Dep

th (f

eet b

gs)

----

--Fu

els

( AK

102,

AK

102,

and

AK

103)

Gas

olin

e R

ange

Org

anic

s1,

400

300

----

----

[0.7

67]

ND

0.69

2F

----

----

----

----

8.46

J1.

68F,

J10

.4=

----

----

----

[2.5

4]N

D10

.4=

3/4

0/4

No

Die

sel R

ange

Org

anic

s10

,250

250

946

=64

6=

93.5

=13

.1F

12,8

00=

17,7

00=

127

=21

6=

7,74

0=

8,50

0=

183

=41

9J

250

J26

7=

----

17,7

00=

12/1

22/

12Y

esR

esid

ual R

ange

Org

anic

s10

,000

11,0

0045

7=

103

=37

.8=

7.59

F1,

570

=5,

300

=27

8=

654

=60

7=

642

=36

7=

1,24

0J

596

J2,

550

=--

--5,

300

=12

/12

0/12

No

Ben

zene

110.

025

----

----

[0.0

0409

]N

D[0

.003

63]

ND

----

----

----

----

[0.0

057]

ND

[0.0

0494

]N

D[0

.004

64]

ND

----

----

----

[0.0

0406

]N

D[0

.005

7]N

D0/

40/

4N

oE

thyl

benz

ene

110

6.9

----

----

[0.0

153]

ND

[0.0

136]

ND

----

----

----

----

[0.0

214]

ND

[0.0

185]

ND

[0.0

174]

ND

----

----

----

[0.0

152]

ND

[0.0

214]

ND

0/4

0/4

No

Tolu

ene

220

6.5

----

----

0.02

97F

[0.0

136]

ND

----

----

----

----

[0.0

214]

ND

[0.0

185]

ND

[0.0

174]

ND

----

----

----

[0.0

152]

ND

0.02

97F

1/4

0/4

No

o-X

ylen

e--

----

----

--[0

.015

3]N

D[0

.013

6]N

D--

----

----

----

--0.

157

=0.

027

F0.

109

=--

----

----

--[0

.015

2]N

D0.

157

=2/

40/

4N

oP

& M

-Xyl

ene

----

----

----

[0.0

153]

ND

[0.0

136]

ND

----

----

----

----

[0.0

214]

ND

[0.0

185]

ND

0.03

58F

----

----

----

[0.0

152]

ND

0.03

58F

1/4

0/4

No

Tota

l Xyl

ene

6363

----

----

[0.0

153]

ND

[0.0

136]

ND

----

----

----

----

0.15

7=

0.02

7F

0.14

5F

----

----

----

[0.0

152]

ND

0.15

7=

2/4

0/4

No

1-M

ethy

lnap

htha

lene

280

6.2

----

----

0.02

01=

----

7.42

=--

----

----

--9.

56=

9.79

=--

----

----

----

----

--9.

79=

3/3

0/3

No

2-M

ethy

lnap

htha

lene

280

6.1

----

----

0.02

66=

----

9.66

=--

----

----

--[0

.016

4]N

D[0

.016

7]N

D--

----

----

----

----

--9.

66=

2/3

0/3

No

Ace

naph

then

e2,

800

180

----

----

[0.0

0171

]N

D--

--0.

427

=--

----

----

--0.

678

=0.

511

=--

----

----

----

----

--0.

678

=2/

30/

3N

oA

cena

phth

ylen

e2,

800

180

----

----

[0.0

0171

]N

D--

--[0

.016

7]N

D--

----

----

--[0

.016

4]N

D[0

.016

7]N

D--

----

----

----

----

--[0

.016

7]N

D0/

30/

3N

oA

nthr

acen

e20

,600

3,00

0--

----

--[0

.001

71]

ND

----

0.57

4=

----

----

----

0.29

2=

0.26

3=

----

----

----

----

----

0.57

4=

2/3

0/3

No

Ben

zo(a

)Ant

hrac

ene

4.9

3.6

----

----

[0.0

0171

]N

D--

--0.

0674

=--

----

----

--0.

051

F0.

0558

=--

----

----

----

----

--0.

0674

=2/

30/

3N

oB

enzo

[a]p

yren

e0.

492.

1--

----

--[0

.001

71]

ND

----

0.08

44=

----

----

----

0.05

56=

0.06

07=

----

----

----

----

----

0.08

44=

2/3

0/3

No

Ben

zo[b

]Flu

oran

then

e4.

912

----

----

0.00

437

F--

--0.

052

F--

----

----

--0.

0314

F0.

0329

F--

----

----

----

----

--0.

052

F3/

30/

3N

oB

enzo

[g,h

,i]pe

ryle

ne1,

400

38,7

00--

----

--[0

.001

71]

ND

----

0.05

37F

----

----

----

0.04

63F

0.04

15F

----

----

----

----

----

0.05

37F

2/3

0/3

No

Ben

zo[k

]fluo

rant

hene

4912

0--

----

--[0

.001

71]

ND

----

[0.0

167]

ND

----

----

----

[0.0

164]

ND

[0.0

167]

ND

----

----

----

----

----

[0.0

167]

ND

0/3

0/3

No

Chr

ysen

e49

036

0--

----

--[0

.001

71]

ND

----

0.11

8=

----

----

----

0.08

46=

0.09

77=

----

----

----

----

----

0.11

8=

2/3

0/3

No

Dib

enzo

[a,h

]ant

hrac

ene

0.49

4--

----

--[0

.001

71]

ND

----

0.01

77F

----

----

----

[0.0

164]

ND

[0.0

167]

ND

----

----

----

----

----

0.01

77F

1/3

0/3

No

Fluo

rant

hene

1,90

01,

400

----

----

[0.0

0171

]N

D--

--[0

.016

7]N

D--

----

----

--0.

0581

=0.

0468

F--

----

----

----

----

--0.

0581

=2/

30/

3N

oFl

uore

ne2,

300

220

----

----

0.00

312

F--

--2.

11=

----

----

----

1.84

=1.

77=

----

----

----

----

----

2.11

=3/

30/

3N

oIn

deno

[1,2

,3-c

,d] p

yren

e4.

941

----

----

[0.0

0171

]N

D--

--0.

0269

F--

----

----

--[0

.016

4]N

D[0

.016

7]N

D--

----

----

----

----

--0.

0269

F1/

30/

3N

oN

apht

hale

ne28

20--

----

--0.

0072

2=

----

1.99

=--

----

----

--[0

.016

4]N

D[0

.016

7]N

D--

----

----

----

----

--1.

99=

2/3

0/3

No

Phe

nant

hren

e20

,600

3,00

0--

----

--[0

.001

71]

ND

----

0.62

8=

----

----

----

1.74

=1.

8=

----

----

----

----

----

1.8

=2/

30/

3N

oP

yren

e1,

400

1,00

0--

----

--[0

.001

71]

ND

----

0.16

6=

----

----

----

0.18

2=

0.20

4=

----

----

----

----

----

0.20

4=

2/3

0/3

No

Aro

clor

-101

6--

--[0

.016

1]N

D[0

.017

1]N

D[0

.016

8]N

D[0

.015

6]N

D[0

.016

7]N

D[0

.016

2]N

D[0

.015

7]N

D[0

.015

8]N

D[0

.016

5]N

D[0

.167

]N

D[0

.16]

ND

[0.1

6]N

D[0

.079

2]N

D[0

.158

]N

D--

--[0

.167

]N

D0/

120/

12N

oA

rocl

or-1

221

----

[0.0

161]

ND

[0.0

171]

ND

[0.0

168]

ND

[0.0

156]

ND

[0.0

167]

ND

[0.0

162]

ND

[0.0

157]

ND

[0.0

158]

ND

[0.0

165]

ND

[0.1

67]

ND

[0.1

6]N

D[0

.16]

ND

[0.0

792]

ND

[0.1

58]

ND

----

[0.1

67]

ND

0/12

0/12

No

Aro

clor

-123

2--

--[0

.016

1]N

D[0

.017

1]N

D[0

.016

8]N

D[0

.015

6]N

D[0

.016

7]N

D[0

.016

2]N

D[0

.015

7]N

D[0

.015

8]N

D[0

.016

5]N

D[0

.167

]N

D[0

.16]

ND

[0.1

6]N

D[0

.079

2]N

D[0

.158

]N

D--

--[0

.167

]N

D0/

120/

12N

oA

rocl

or-1

242

----

[0.0

161]

ND

[0.0

171]

ND

[0.0

168]

ND

[0.0

156]

ND

[0.0

167]

ND

[0.0

162]

ND

[0.0

157]

ND

[0.0

158]

ND

[0.0

165]

ND

[0.1

67]

ND

[0.1

6]N

D[0

.16]

ND

[0.0

792]

ND

[0.1

58]

ND

----

[0.1

67]

ND

0/12

0/12

No

Aro

clor

-124

8--

--[0

.016

1]N

D[0

.017

1]N

D[0

.016

8]N

D[0

.015

6]N

D[0

.016

7]N

D[0

.016

2]N

D[0

.015

7]N

D[0

.015

8]N

D[0

.016

5]N

D[0

.167

]N

D[0

.16]

ND

[0.1

6]N

D[0

.079

2]N

D[0

.158

]N

D--

--[0

.167

]N

D0/

120/

12N

oA

rocl

or-1

254

----

[0.0

161]

ND

[0.0

171]

ND

[0.0

168]

ND

[0.0

156]

ND

[0.0

167]

ND

[0.0

162]

ND

[0.0

157]

ND

[0.0

158]

ND

[0.0

165]

ND

[0.1

67]

ND

[0.1

6]N

D[0

.16]

ND

[0.0

792]

ND

[0.1

58]

ND

----

[0.1

67]

ND

0/12

0/12

No

Aro

clor

-126

0--

--0.

195

=0.

132

=96

.9=

10.1

=24

.8=

89.1

=0.

153

=11

2=

0.66

1=

0.67

=3.

36=

30.8

=24

.7=

45=

----

112

=12

/12

8/12

Yes

Tota

l PC

Bs8

1.0

1.0

0.19

5=

0.13

2=

96.9

=10

.1=

24.8

=89

.1=

0.15

3=

112

=0.

661

=0.

67=

3.36

=30

.8=

24.7

=45

=--

--11

2=

12/1

28/

12Y

esPe

rcen

t Sol

ids

(SM

2540

G)

Tota

l Sol

ids

--92

.4=

86.2

=87

.5=

95.3

=89

.6=

91.3

=93

.5=

93.9

=89

.9=

88.8

=92

.9=

93.8

=93

.4=

94.1

=--

----

----

Not

es:

1 - P

rimar

y S

cree

ning

Crit

eria

: th

e cl

eanu

p le

vel c

orre

spon

ds to

the

low

est v

alue

for d

irect

con

tact

or i

nhal

atio

n of

soi

l as

liste

d in

18

AA

C 7

5.34

1, T

able

s B

1 an

d B

2, (M

etho

d Tw

o cl

eanu

p le

vels

) for

the

unde

r 40

inch

zon

e (O

ctob

er 9

, 200

8).

3 - T

he fi

eld

sam

ple

iden

tific

atio

n nu

mbe

r, da

te c

olle

cted

and

labo

rato

ry s

ampl

e id

entif

icat

ion

num

ber a

re p

rovi

ded.

The

sam

ple

dept

h in

feet

is li

sted

afte

r the

hyp

hen

at th

e en

d of

the

sam

ple

iden

tific

atio

n nu

mbe

r.

5 - A

par

ent a

nd d

uplic

ate

sam

ple

are

coun

ted

as o

ne s

ampl

e. T

he h

ighe

r of t

he tw

o va

lues

are

use

d fo

r the

pur

pose

of c

ount

ing

dete

ctio

ns a

nd e

xcee

danc

es.

Trip

bla

nks

are

not i

nclu

ded.

6 - S

cree

ning

crit

eria

val

ues

are

from

18

AA

C 7

5.34

1 M

etho

d Tw

o U

nder

40-

inch

Zon

e. T

otal

val

ues

are

the

sum

mat

ion

of d

etec

ted

com

poun

ds o

nly.

If a

ll va

lues

are

non

dete

ctab

le, t

he h

ighe

st M

DL

is s

how

n.

Dat

a Fl

ags

ND

nond

etec

t, m

etho

d de

tect

ion

limit

is p

rese

nted

in b

rack

ets

to th

e le

ftJ

estim

ated

val

ue, a

"+" o

r "-"

indi

cate

s a

posi

tive

or n

egat

ive

bias

Fre

porte

d va

lue

was

bet

wee

n th

e la

bora

tory

MD

L an

d P

QL

=A

det

ecte

d co

mpo

und

(con

cent

ratio

n lis

ted

in c

olum

n to

the

left)

Bco

mpo

und

was

det

ecte

d in

the

met

hod

blan

k or

trip

bla

nk

Abb

revi

atio

ns--

Not

app

licab

le o

r scr

eeni

ng c

riter

ia d

oes

not e

xist

for t

his

com

poun

dm

g/K

gm

illig

ram

s pe

r kilo

gram

AA

CA

lask

a A

dmin

istra

tive

Cod

eP

CB

Pol

ychl

orin

ated

Bip

heny

lbg

sbe

low

gro

und

surfa

ceP

QL

Pra

ctic

al Q

uant

itatio

n Li

mit

CO

CC

onta

min

ant o

f Con

cern

SIM

Sel

ectiv

e Io

n M

onito

ring

MD

LM

etho

d D

etec

tion

Lim

it

bold

and

sha

ded

- val

ue e

xcee

ds p

rimar

y sc

reen

ing

crite

ria (M

etho

d Tw

o C

lean

up L

evel

s)sh

aded

- va

lue

exce

eds

Met

hod

Two

mig

ratio

n to

gro

undw

ater

cle

anup

leve

ls.

Rep

licat

eTE

W-9

.814

-Sep

-09

1094

8730

10

--

Trip

Bla

nk

--6.

04.

01.

50.

51.

5--

TEW

-4.0

14-S

ep-0

910

9487

3011

4.0

6.0

6.5

4.0

1.5

0.5

6.0

TES

-6.5

14-S

ep-0

910

9487

3005

TES

-4.0

14-S

ep-0

910

9487

3006

TES

-1.5

14-S

ep-0

910

9487

3007

TES

-0.5

14-S

ep-0

910

9487

3008

Prim

ary

TEW

-6.0

14-S

ep-0

910

9487

3009

6.5

TEN

-6.0

14-S

ep-0

910

9487

3002

TEE

-6.5

14-S

ep-0

910

9487

3003

TEE

-4.0

14-S

ep-0

910

9487

3004

4.0

Con

tam

inan

t of

Con

cern

(C

OC

)7

Com

poun

d m

illig

ram

s pe

r kilo

gram

(m

g/K

g)

Met

hod

Two

(und

er 4

0-in

ch

zone

)1

Met

hod

Two

Mig

ratio

n to

G

roun

dwat

er2

Sam

ple

Loca

tions

3

Max

imum

C

once

ntra

tion4

Freq

uenc

y of

Det

ectio

n5

Rep

licat

eTE

W-9

.914

-Sep

-09

1094

8730

13

TEW

-0.5

14-S

ep-0

910

9487

3014

Trip

Bla

nk14

-Sep

-09

1094

8730

17

4 - T

he m

axim

um c

once

ntra

tion

of a

det

ecte

d an

alyt

e is

sho

wn.

If a

n an

alyt

e w

as n

ot d

etec

ted,

then

the

high

est M

DL

is s

how

n. T

rip b

lank

s ar

e no

t inc

lude

d.

7 - A

com

poun

d is

con

side

red

a C

OC

if it

exc

eeds

the

prim

ary

scre

enin

g cr

iteria

.8

- Tot

al v

alue

s w

ere

the

sum

mat

ion

of d

etec

ted

com

poun

ds o

nly.

If c

ompo

unds

wer

e no

t det

ecte

d, th

en th

e hi

ghes

t MD

L w

as li

sted

.

Freq

uenc

y A

bove

Pr

imar

y Sc

reen

ing

Crit

eria

5,6

Ben

zene

, Eth

ylbe

nzen

e, T

olue

ne, a

nd X

ylen

es (S

W80

21B

)

Poly

nucl

ear A

rom

atic

Hyd

roca

rbon

s (S

W82

70D

SIM

)

Poly

chlo

rinat

ed B

iphe

nyls

(SW

8082

)

2 - S

econ

dary

Scr

eeni

ng C

riter

ia:

the

valu

e co

rres

pond

s to

the

valu

e lis

ted

in 1

8 A

AC

75.

341,

Tab

les

B1

and

B2,

Mig

ratio

n to

Gro

undw

ater

(Oct

ober

9, 2

008)

.

Prim

ary

TEW

-1.5

14-S

ep-0

910

9487

3012

TEN

-4.0

14-S

ep-0

910

9487

3001

3-1

3

UST

Rel

ease

Inve

stig

atio

n Re

port

M

L&P

Ope

ratio

ns a

nd D

ispa

tch

Cen

ter

Prep

ared

for M

unic

ipal

Lig

ht &

Pow

er

1-

7

N

ovem

ber 2

009

This

pag

e in

tent

iona

lly le

ft bl

ank.

sheiges

Text Box

3-14



4 SUMMARY AND CONCLUSIONS

Visual observations and sampling and analysis have confirmed a release of diesel fuel occurred from an inactive UST next to the ML&P Operations Building (1121 E. 1st Ave, Anchorage, AK). The duration of the release(s) or the total quantity of fuel released is unknown. However, the site history and sample results (both current and past) suggest the release was less than 2,000 gallons and the impacts are localized. The UST was emptied of product and removed from the ground in September of 2009, stopping the potential for future releases. Sampling indicated that there was also a PCB spill located in the same approximate location as the UST. The source of the PCBs is assumed to be spills or leaks of dielectric fluids from a transformer that was located a few feet from the UST prior to 1974. The fuel release appears to have enabled the PCBs to migrate within the fuel-saturated zone and in some areas the contaminants are commingled. Limited soil removal was performed in combination with the UST removal and the associated water line installation project. After the removal action was complete, soil sampling and analysis detected contaminants above ADEC regulatory cleanup levels (18 AAC 75.341) along the edges of the excavation. Based on these results, the primary contaminants of concern (COCs) at the site are DRO and PCBs. PAHs are also potential COCs. Along the edges of the UST excavation, DRO and PCBs exceeded the ADEC Method Two cleanup level for the under 40-inch zone (direct contact or ingestion). The maximum detected DRO concentration was 17,700 mg/Kg, and the maximum detected PCB concentration was 112 mg/Kg. Two PAH compounds (1-methylnaphthalene and 2-methylnaphalene) slightly exceeded the Method Two Migration to Groundwater cleanup standard. It is also suspected that a portion of the soil used to backfill the excavation contained PCBs above 1 mg/Kg, and possibly above 50 mg/Kg, as soil from the excavation was used for backfill before it was known PCBs were present. The soil removed from the UST excavation for disposal (12 yd3) had a maximum detected PCB concentration of 114 mg/Kg and DRO of 2,550 mg/Kg. At the nearby Water Line Excavation, no sample concentrations exceeded the ADEC Method Two cleanup level for the under 40-inch zone after the removal action was complete. However, DRO and two chlorinated solvents (tetrachloroethene and trichloroethene) exceeded the most stringent ADEC Method Two cleanup level (Migration to Groundwater). The highest DRO concentration detected was 2,140 mg/Kg. This sample was located at a depth of 6.5 feet bgs in the small excavation within the Operations Building. The two chlorinated solvents exceeded the Migration to Groundwater Cleanup Level at this location as well. PCBs were detected but no sample concentrations exceeded 1 mg/Kg. The contaminated soil detected at the Water Line Excavation is attributed to migration from adjacent sources areas, the dominant source being the UST area. Product (fuel) was observed flowing into the excavation from the UST area in September 2009. It is also possible some of the detected petroleum hydrocarbons on the west side of the Water Line Excavation originated from the Gasoline UST site to the west. The low levels of chlorinated solvents detected in the soils



are likely the result of transport from offsite locations. There is documented contamination of chlorinated solvents in the ground water in the region (e.g., The RETEC Group 2008; BGES 2007; CH2MHill 2008). Groundwater sampling was not performed as part of this investigation. However, based on visual observations and soil sampling results, impacts to ground water are likely, at least in the immediate area. Potentially, some free product is still present. However, given the dewatering and product recovery efforts conducted for several weeks during and after UST removal, it is likely most if not all residual product is relatively immobile and localized. Current information, albeit limited, does not indicate there are current exposure pathways between the COCs and human or ecological receptors. Contamination appears to be localized and confined within the subsurface of the facility boundaries. The contaminated soil is covered by concrete or asphalt, preventing contact between potential receptors and the soil. Volatile components are low, indicating vapors are unlikely to pose a significant risk. There are no drinking water wells on the property or adjacent properties, and surface water bodies are not present. These circumstances suggest the site poses a low risk to human health or the environment given the current site conditions. As a result of this release investigation, several recommendations are offered for consideration:

• Appropriate institutional controls should be put in place and maintained to prevent the exposure to contaminants at adverse concentrations.

• Additional site characterization should be performed to define the extent of contamination, evaluate the potential for offsite migration, and determine the appropriate management strategy for the site. At a minimum, groundwater monitoring of existing groundwater wells should be performed to confirm that contaminants are not migrating beyond the immediate area and potentially reaching downgradient receptors. This sampling was initiated in October 2009 and results are pending. Soil sampling for PCBs and DRO beyond the boundaries of the UST excavation is also advisable.

• PCB concentrations in excess of 50 mg/Kg were detected and remain in the soil at the site. Therefore, the cleanup and disposal of the PCB-contaminated soil must comply with applicable TSCA regulations (40 CFR 761.61) unless the EPA approves alternative requirements as part of a risk-based disposal under 40 CFR 761.61(c). Under 40 CFR 761.61(a), self-implementing onsite cleanup and disposal of PCB remediation waste, the EPA has established cleanup levels and associated institutional controls for PCB remediation waste (contaminated soil). Under these regulations, the PCB cleanup level for soil varies from 1 to 100 mg/Kg depending upon the site use (occupancy). The cleanup levels and institutional controls applicable to a “low occupancy area” are probably appropriate for the site and could be implemented fairly readily. Under these regulations, soil with PCBs greater than 100 mg/Kg must be removed unless risk-based disposal is approved in accordance with 40 CFR 761.61(c). The site management strategy should consider whether removal of the PCB-contaminated soil to some threshold level (e.g., 100, 50 or 25 mg/Kg) is preferred over the implementation of more restrictive institutional controls. Removal actions will be complicated by the existing infrastructure (utilities and buildings) and shallow water table. Therefore, the most



practical approach may be a combination of removal actions and institutional controls, contingent upon regulator approval.



5 REFERENCES

Alaska Department of Environmental Conservation (ADEC). 2002. Underground Storage

Tanks Procedures Manual. November 7. ADEC. 2009. Environmental Laboratory Data and Quality Assurance Requirements. Technical

Memorandum. March. BGES, Inc. (BGES). 2007. Forth Avenue and Gambell Street, Anchorage Alaska. Additional Site

Assesment. December. CH2M HILL. 2008. Area GW 2/3 Supplemental Groundwater Investigation in the Vicinity of

the Alaska Railroad Corporation, Anchorage Terminal Reserve. Prepared for the U.S. EPA. November.

Freeze, Allan R. and Cherry, John A. 1979. Groundwater, Prentice-Hall Englewood Cliffs,

New Jersey. 604 pp. Hoefler Consulting Group (HCG). 2009a. Letter to ML&P entitled: Re: July 2009 Groundwater

Monitoring at 1121 E. 1st Avenue, Anchorage, Alaska, File #2100.26.301, Fac. ID #73, Event ID #78, Reckey #1989210008601. August 25.

HCG. 2009b. Cleanup Plan for Petroleum Contaminated Soil in the “Water Line Excavation,”

ML&P Operations and Dispatch Center, 1201 E. 1st Ave, Anchorage, Alaska. September.

HCG. 2009c. Work Plan for Limited Release Investigation and Soil Removal Action During UST

Removal at ML&P Operations and Dispatch Center, 1201 E. 1st Ave, Anchorage, Alaska. September.

HCG. 2009d. Data Report for October 2009 Groundwater Sample Results, ML&P Operations

and Dispatch Center, 1201 E. 1st Ave, Anchorage, Alaska. (In Progress). Anticipated November.

META Environmental. 1994. Site Characterization and Remediation Alternatives Study at

ML&P Power Plant No. 1. November. M.L. Taylor and P.W. Kilpatrick, Architects. 1953. Schematic drawing: Floor Plan, Sheet 16 of

18, Heating. June 4. Matthews, Jerry. 2009. Personal communication between Mr. Mathews, ML&P Distribution

Transformer Shop/Facility Maintenance, and HCG staff, September through November.



Shannon & Wilson. 1993. Document Review and Groundwater Monitoring Results. 1121 East First Avenue, Anchorage, Alaska. September.

Shannon & Wilson. 2003. ML&P Property Review and Status, East First and Third Avenues,

Anchorage, Alaska. Jul The RETEC Group, Inc. 2008. Remedial Investigation, Alaska Railroad Corporation,

Anchorage Terminal Reserve, U.S. EPA Docket No. CERCLA 10-2004-0065. May 12.


Prepared for Municipal Light & Power November 2009

Appendix A

1953 Operations Building Schematic Drawing

UST Release Investigation Report · 2009. 11. 1. · The treatment system operated until February...

Documents

Transcript of UST Release Investigation Report · 2009. 11. 1. · The treatment system operated until February...