Project No.: October 10, Ed Jones, Department of Ecology, NWRO

Transcription

1 MEMORANDUM Project No.: -012 October 10, 2014 To: Ed ones, Department of Ecology, NWRO cc: Blaser Die-Casting, Inc. and Pacific Groundwater Group Burlington Environmental, LLC and Pacific Crest Consulting, LLC Capital Industries, Inc. and Farallon Consulting, LLC Art Brass Plating, Inc. From: Re: Aspect Consulting, LLC Draft Site Conceptual Model Technical Memorandum W4 oint Deliverable This draft Site Conceptual Model Technical Memorandum was prepared on behalf of the four potentially liable parties (PLPs) [Art Brass Plating (ABP), Blaser Die Casting (BDC), Capital Industries (CI), and PSC Environmental Services, LLC (PSC)] identified by the Washington State Department of Ecology (Ecology) in Agreed Order (AO) No. DE10402 for the West of 4 th (W4) Site. The AO requires the four PLPs (the W4 Group) to complete a Feasibility Study (FS) and prepare a draft Cleanup Action Plan (dcap) for the W4 Site. The environmental consultants addressing technical aspects of the FS and dcap on behalf of the W4 Group (W4 Consultants) are: Aspect Consulting (Aspect) for ABP; Farallon Consulting (Farallon) for CI; Pacific Groundwater Group (PGG) for BDC; and Pacific Crest Environmental (Pacific Crest) for PSC. Overview The Site Conceptual Model has been developed to identify: Sources of constituents of concern (COCs); Nature and extent of contamination; and nown and potential exposure pathways and receptors. The Preliminary Site Cleanup Standards memorandum (Farallon, 2014) identified Site COCs, media of potential concern, preliminary site cleanup standards, and exposure pathways. This Site Conceptual Model memorandum is a continuation of that analysis. The source of data used for this analysis is a compilation of data that has been collected by ABP, BDC, CI, and PSC. Data are compiled in the separate Remedial Investigations (RIs) reports completed by ABP (Aspect, 2012), e a r t h + w a t e r Aspect Consulting, LLC 401 2nd Avenue S. Suite 201 Seattle, WA

2 MEMORANDUM October 10, 2014 Project No.: -012 CI (Farallon, 2012), BDC (PGG, 2012), and PSC (PSC, 2003). Data collected subsequent to issuing the RI reports, primarily groundwater, have been reported to Ecology quarterly in progress reports. The Site Conceptual Model identifies critical assumptions to be used in the FS and during contaminant fate and transport analysis. A summary of these critical assumptions is provided in Table 1 with a more detailed discussion provided below. COCs by Site Unit are identified in the Preliminary Site Cleanup Standards memorandum (Farallon, 2014). Sources of COCs Three known facilities located in the Site area have been identified as sources of contamination: ABP Facility located at rd Avenue South; BDC Facility located at rd Avenue South; and CI Facility located at rd Avenue South. The PSC Facility is located at 734 Lucile Street, on the east side of 4 th Avenue South. PSC is included as a PLP for the W4 Site due to the migration of COCs in groundwater from the East of 4th area into the Site. Figure 1 illustrates the location of these facilities. The following provides a summary of the sources of COCs from these facilities. Art Brass Plating The ABP Facility is the property located at rd Avenue South. Since 1983, the Facility has been operated exclusively for metal plating and related work (e.g., metal polishing and powder coating). Metal plating has included nickel, chrome, brass (an alloy of copper and zinc), copper, and gold. The chlorinated solvent trichloroethene (TCE) was formerly used at the ABP Facility for vapor degreasing from approximately 1983 to February Since 1983, the vapor degreaser has been located at its current location just south of the polishing area, labeled Former TCE Degreaser No. 1 on Figure 2. A second vapor degreaser, located in what is now the Time-Saver Room, was temporarily used between 1988 and 1993, labeled Former TCE Degreaser No. 2 on Figure 2. Environmental investigations confirm the release of chlorinated solvents and plating metals from the ABP Facility to soil and groundwater. The investigation data show the downgradient migration of TCE and its degradation products DCE and vinyl chloride via groundwater flow. These data also indicate the historical release of plating solutions resulting in depressed p and elevated concentrations of cadmium, copper, nickel, and zinc in soil and groundwater beneath, and in close proximity to, the ABP Facility. In September 2008, ABP installed an air sparging (AS) and soil vapor extraction (SVE) system to remove chlorinated COCs from soil and groundwater at and around the Facility. The AS/SVE system has operated continuously (except for periodic shutdowns for monitoring and maintenance) since being installed until In late 2011, the AS portion of the system has been switched to a pulsed operation where it is on for six months then off for six months for more efficient removal. The system has removed approximately 85 pounds of TCE from the subsurface, and groundwater concentrations of TCE have declined 90 to 99 percent at wells in and around the treatment area. As reported in ABP RI, residual soil contamination remains on the property that exceeds preliminary soil cleanup standards for protective of groundwater (Aspect, 2012). Page 2

3 MEMORANDUM October 10, 2014 Project No.: -012 Blaser Die Casting The BDC Facility is the property located at rd Avenue South. BDC has occupied its present location since 1962 and performed die casting until 2010 when the building was converted to a storage and distribution facility. BDC s processes did not change substantively since The review of site processes, materials, waste oil testing, and interviews of key employees provided no records that TCE has ever been used by BDC or that TCE was ever used at the property. Nevertheless, a release of TCE occurred sometime before 1996 when a building addition was constructed at BDC. The building is currently used as warehouse and temporary storage space. Soil and groundwater data indicated a TCE release to on-site soils that are now beneath the southwest corner of the BDC addition (Figure 3). BDC completed a soil source control action at the building in anuary The source control action included removal of 1,200 tons of contaminated soil and 7,250 gallons of contaminated groundwater from the excavation at the southwest corner of the building. The action excavated soil below the water table by dewatering to about ~8 feet below ground surface. The excavation was extended laterally until confirmation samples indicated that the source was removed or existing structures or utilities impeded further excavation. Some residual soil located on the property exceeds soil screening levels protective of groundwater at the north end of the excavation where excavation was not feasible. Subsequent groundwater monitoring has demonstrated a more than 98% decrease in source area groundwater concentrations. Capital Industries Former operations at the CI Facility that may have resulted in releases of TCE and/or tetrachloroethene (PCE) to soil and groundwater include use of a vapor degreaser formerly located in Capital Plant 4, and use of a solvent-based parts cleaner formerly located in Capital Plant 2. There is no documented record of a significant release of solvents from either of these units. Nevertheless, concentrations of PCE and/or TCE have been confirmed present in soil, groundwater, and/or soil gas at the CI Facility. A site plan of the CI Facility is provided on Figure 4. Plant 4 The nature and extent of TCE, PCE, and related chlorinated volatile organic compounds (CVOCs) in soil and groundwater in the Water Table Interval suggest that a release(s) of TCE and/or PCE may have occurred from degreasing operations that formerly took place in the Capital Plant 4 building. Sufficient sampling was performed to estimate the distribution of CVOCs in the affected media during the RI. No interim action was performed due to the relatively low concentrations and limited distribution of CVOCs in soil. Plant 2 The nature and extent of CVOCs in groundwater in the Water Table Interval suggest that a release(s) of TCE may have occurred from a degreaser formerly located at the southwest corner of Capital Plant 2, and from the former storage of chemicals at the Capital Plant 2 Canopy. The results of the pre-ri investigations, soil gas monitoring, and soil sampling conducted during the excavation and reconstruction of the Capital Plant 2 building following a fire that destroyed the building, and during the RI did not detect residual concentrations of CVOCs in soil that suggested an extensive or significant release of CVOCs at the Capital Plant 2 building or the Capital Plant 2 Canopy. Nevertheless, the Water Table Interval groundwater reconnaissance and monitoring well data indicate a source of CVOCs is likely present. Page 3

4 MEMORANDUM October 10, 2014 Project No.: -012 Soil beneath Capital Plant 2 was excavated for the foundation and utility trenches for reconstruction of Capital Plant 2 in 2004 following the destruction of the building by a fire. Although the excavation activities resulted in removal of soil in the Capital Plant 2 and Canopy area, soil testing performed on the excavated materials did not detect concentrations of CVOCs suggesting the source(s) at Capital Plant 2 and the associated Capital Plant 2 Canopy were not removed during reconstruction activities. The Water Table Interval groundwater data indicate the source(s) of CVOCs likely persists but appears to be attenuating, confirming the RI conclusions that significant sources of TCE are not present at the Capital Plant 2 and Capital Plant 2 Canopy areas. PSC PSC operated the former hazardous waste management facility at 734 South Lucile Street, east of 4 th Avenue South. The dangerous waste facility consists of two adjacent and contiguous parcels of property, the original permitted parcel consisting of approximately two (2) acres located at 734 Lucile Street and an unpermitted parcel of approximately four (4) acres (the former Amalgamated Sugar Company or TASCO property) located at 5400 Denver Avenue. PSC closed the operating portion of the facility effective December During the RI, PSC performed soil, soil gas, and groundwater sampling on and in the vicinity of their property. Concentrations exceeding applicable cleanup levels, due to facility releases, have been detected on and to the north and east of the 734 South Lucile Street property. azardous substances due to releases have also contaminated groundwater. azardous substances in groundwater migrate in the direction of regional groundwater flow which is generally westerly-tosouthwesterly. This has resulted in contaminated groundwater located east and west of 4th Avenue South. The eastern area of the PSC site, east of 4th Avenue South, is being addressed under a May 2010 Cleanup Action Plan and Agreed Order DE #7347. PSC has implemented interim actions, which have included construction of a subsurface barrier wall (also known as the hydraulic containment interim measure - CIM) that surrounds most of the 734 Lucile Street and 5400 Denver Avenue South properties. The CIM was constructed to minimize or eliminate the downgradient migration of hazardous substances in groundwater. Environmental Setting The environmental setting for the Site has been discussed in detail in the RI reports prepared by ABP (Aspect, 2012), BDC (PGG, 2012), CI (Farallon, 2012), and PSC (PSC, 2003). This section provides a brief overview to support the nature and extent discussion below. The hydrogeologic units encountered in borings completed at the Site include a Younger Alluvium and Older Alluvium. The upper portion of the Younger Alluvium has been modified and is referred to as the Fill Unit. A description of these units is provided below. Fill Unit consists of heterogeneous layers of gravelly sand, silt, and silty sand with scattered bits of inert debris such as glass shards or brick fragments. This unit extends up to a depth of 8 feet however the boundary between the Fill Unit and the Younger Alluvium is difficult to distinguish. Page 4

5 MEMORANDUM October 10, 2014 Project No.: -012 Younger Alluvium (Qyal) represents channel and overbank/floodplain deposits from the Duwamish River (Booth and erman, 1998). At the Site, the Younger Alluvium consists of two subunits, a sandy silt or silty sand unit overlying slightly silty fine-medium sand unit. Scattered bits of wood and organic debris are also present. This unit is typically found within a few feet above or below the current sea level and extends to a depth of approximately 25 to 30 feet. Moving westward towards the Duwamish Waterway (Waterway), the Younger Alluvium extends to a depth of approximately 55 feet. Older Alluvium (Qoal) represents materials deposited in an estuarine and deltaic environment. The Older Alluvium consists of interbedded sequences of silty fine sand and sandy silt. A silt aquitard, likely a subunit of the Older Alluvium, and bedrock have been identified in deeper borings east of 4th Avenue (PSC, 2003). These additional units were not encountered in the borings located at the Site. Based on a review of the Duwamish Valley cross sections available in Booth and erman (1998), it is expected that the silt aquitard and bedrock are present at a depth greater than 150 feet. The lithologic units discussed above correspond to the hydrogeologic units encountered at the Site. PLPs use a standardized nomenclature for groundwater monitoring and sampling intervals which are: Water Table Interval. This interval includes monitoring wells screened above 20 feet below ground surface (bgs) and reconnaissance groundwater samples collected above 20 feet bgs. Shallow Interval. This interval includes monitoring wells screened below 20 feet and above 40 feet bgs, and reconnaissance groundwater samples collected between 21 feet and 40 feet bgs. Intermediate Interval. This interval includes monitoring wells and reconnaissance groundwater samples screened below 40 feet bgs. Groundwater Flow and Tidal Variability Groundwater flow at the Site is to the west and southwest. Little seasonal variability in flow direction is observed. Vertical gradient between the Water Table and Shallow Intervals are typically downward. Vertical gradients between the Shallow and Intermediate Intervals fluctuate between upward and downward except in the well clusters close to the Waterway, west of East Marginal Way. Upward gradient were typical in these well pairs. Tidal studies are detailed in RI reports from ABP (Aspect, 2012) and CI (Farallon, 2012). Water levels in the Waterway are influenced by river flow and tidal effects from Puget Sound. igh tides result in localized groundwater flow gradient reversal, although the time-averaged net groundwater flow direction is still toward the Waterway. The occurrence of localized and transient flow reversals is consistent with site characterization data collected at other similar sites in the Waterway, and with the Site RI data. Tidal influences on water levels diminish to 0.5 feet or less approximately 800 feet east/northeast (upgradient) of the Waterway. Nature and Extent of Contamination This section provides an overview of the Site data compared to the preliminary cleanup standards (Table 2). The PLP RIs for the four facilities provide a detailed discussion of Site investigation data Page 5

6 MEMORANDUM October 10, 2014 Project No.: -012 as well as tabulated results. Exploration locations are illustrated on Figure 5. Attachment A provides a summary of the available data relative to the cleanup standards including sample counts and number of exceedances. Soil Soil data are discussed in this section, by exposure pathway. Soil data from the vadose zone was used in creating the figures. The vadose zone was defined as soils from the ground surface to a depth of 8 feet, based on a conservative water table depth at the Site. Protection of Direct Contact One soil sample for TCE was the only COC exceedance for direct contact cleanup levels for unrestricted land use. As illustrated in Figure 6, the soil sample is located under the ABP Facility near the source area. No data exceeded direct contact standards for industrial land use. Protection of Surface Water PCE, TCE, and vinyl chloride are the CVOCs that have exceedances for the protection of surface water pathway. Exceedances for PCE (Figure 7) are located near the southeast corner of the CI property. Exceedances for TCE (Figure 8) are located on ABP, BDC, and CI property. For vinyl chloride, two boring locations, one on ABP property and one on CI property, exceed cleanup levels for the protection of surface water (Figure 9). For plating metals (), copper, nickel and zinc exceed the protection of surface water cleanup standards (Figures 10, 11, 12, respectively). 1 1,4-Dioxane soil data is illustrated on Figure 13. Protection of Air PCE, TCE, and vinyl chloride were the three COCs with exceedances (Figures 14, 15, and 16, respectively). Exceedances for PCE are located near the southeast corner of the CI property. TCE exceedances are located on ABP, BDC, and CI properties. Vinyl chloride exceedances are located beneath the ABP and CI Facilities. 1,4-Dioxane soil data is illustrated on Figure 17. Groundwater Nature and extent figures for groundwater illustrate both well data and groundwater grab samples. Well data provides a quantitative measure of groundwater quality conditions. For a given well, the groundwater data illustrated in the figures depicts the most recent available data. Groundwater grab sample data provide a qualitative measure for plume lateral and vertical extent. Probe data are from between 2000 and Where multiple grab samples were collected within a given sampling interval, the highest reported value for that interval is depicted on the figure. Since BDC did an excavation removal action in 2008, data in close proximity to that removal action from before 2009 are not displayed on maps as they do not illustrate current conditions. 1 The partitioning coefficient (d) used to calculate the protection of surface water cleanup standards for metals assumes near neutral p conditions. Past releases at the ABP Facility have resulted in low p conditions beneath and downgradient of the facility. d values for metals decrease with p, which result in lower calculated cleanup standards. p and metals related issues, including cleanup standards, will be explored in more detail in the Fate and Transport Summary Memo. Page 6

7 MEMORANDUM October 10, 2014 Project No.: -012 Protection of Surface Water Chlorinated Solvents PCE, TCE and vinyl chloride are the three CVOCs exceedances of cleanup standards for the protection of surface water (Figures 18, 19, 20, respectively). Chlorinated solvent releases in groundwater migrate to the west and southwest consistent with horizontal gradients at the Site. In the source areas and downgradient plume(s), PCE and TCE undergo reductive dechlorination and form less chlorinated ethenes: dichloroethenes (cis-1,2-dce, 1,1-DCE, trans-1,2-dce) and vinyl chloride. In, the plume migrates upward west of 1st Avenue South to the southwest and extends to the Waterway. At, the existing site characterization data indicates that the CVOC plume does not reach the Waterway. Plume boundaries between and 2 are well defined for PCE and TCE as shown on Figures 18 and 19. owever, vinyl chloride is comingled throughout the Site in the Shallow and Intermediate Intervals as illustrated in Figure 20. Protection of Surface Water Plating Metals In, plating metals copper, nickel, and zinc in groundwater exceed cleanup standards for protection of surface water (Figure 21, 22, 23, respectively). The horizontal extent of plating metals impacts appears limited to a distance of approximately 400 feet downgradient of the ABP Facility. Copper and zinc are limited to the Water Table Interval and Nickel extends to the Shallow Interval. Protection of Surface Water Other Metals Manganese has been detected above cleanup standards for protection of surface water (Figure 24) throughout the Georgetown area. For, arsenic and barium have been identified as COCs and these exceedances are illustrated on Figures 25 and 26, respectively. Protection of Surface Water 1,4-Dioxane As illustrated in Figure 27, the 1,4-dioxane plume extends from the PSC Site east of 4 th Avenue South into the Site at the Shallow and Intermediate Intervals. Plume extent at the Shallow Interval is approximately 4 th Avenue South and 3 rd Avenue South at the Intermediate Interval. Protection of Air Quality CVOCs Groundwater data from the Water Table Interval exceeded cleanup standards for protection of air quality for unrestricted land use for TCE and vinyl chloride. TCE data is illustrated on Figure 28. Vinyl chloride exceedances on Figure 29 are only from groundwater grab samples and vinyl chloride concentrations from adjacent wells are non-detect or below the standard. Porewater In, the CVOC plume has been confirmed to reach the Waterway. Porewater data for vinyl chloride only exceeds cleanup standards for protection of surface water (Figure 30). Exposure Pathways and Receptors Figure 31 provides a graphical presentation of the exposure pathways and receptors for the Site. Page 7

8 MEMORANDUM October 10, 2014 Project No.: -012 References Aspect Consulting, 2012, Remedial Investigation Report, Art Brass Plating, Agency Review Draft, September 27, Booth and erman, 1998, Duwamish Basin Groundwater Pathways Conceptual Model Report, Duwamish Industrial Area ydrogeologic Pathways Project, Prepared for City of Seattle Office of Economic Development and ing County Office of Budget and Strategic Planning, University of Washington and art Crowser,. Farallon, 2012, Revised Draft Remedial Investigation Report, Capital Industries, October Farallon, 2014, Revised Preliminary Site Cleanup Standards Technical Memorandum, W4 oint Deliverable,, Agreed Order No. DE 10402, September 12, Pacific Groundwater Group (PGG), 2012, Revised Remedial Investigation, Blaser Die Casting, August 2, PSC, 2003, Final Comprehensive Remedial Investigation Report For Philip Services Corporation s Georgetown Facility, Philip Services Corporation, November 14, Page 8

9 MEMORANDUM October 10, 2014 Project No.: -012 List of Tables Table 1 Summary of Critical Assumptions Table 2 Summary of Preliminary Cleanup Levels List of Figures Figure 1 Site Diagram Figure 2 Art Brass Plating Facility Map Figure 3 Blaser Die Casting Facility Map Figure 4 Capital Industries Facility Map Figure 5 Exploration Location Map Figure 6 TCE in Vadose Soil, Direct Contact Pathway, Unrestricted Land Use Figure 7 PCE in Vadose Soil, Surface Water Protection Figure 8 TCE in Vadose Soil, Surface Water Protection Figure 9 Vinyl Chloride in Vadose Soil, Surface Water Protection Figure 10 Copper in Vadose Soil, Surface Water Protection Figure 11 Nickel in Vadose Soil, Surface Water Protection Figure 12 Zinc in Vadose Soil, Surface Water Protection Figure 13 1,4-Dioxane in Vadose Soil, Surface Water Protection Figure 14 PCE in Vadose Soil, Protection of Air Quality Figure 15 TCE in Vadose Soil, Protection of Air Quality Figure 16 Vinyl Chloride in Vadose Soil, Protection of Air Quality Figure 17 1,4-Dioxane in Vadose Soil, Protection of Air Quality Figure 18 PCE in Groundwater, Surface Water Protection Figure 19 TCE in Groundwater, Surface Water Protection Figure 20 Vinyl Chloride in Groundwater, Surface Water Protection Figure 21 Copper in Groundwater, Surface Water Protection Figure 22 Nickel in Groundwater, Surface Water Protection Figure 23 Zinc in Groundwater, Surface Water Protection Figure 24 Manganese in Groundwater, Surface Water Protection Figure 25 Arsenic in Groundwater, Surface Water Protection Figure 26 Barium in Groundwater, Surface Water Protection Figure 27 1,4-Dioxane in Groundwater, Surface Water Protection Figure 28 TCE in Water Table Groundwater, Unrestricted Land Use Air Quality Protection Figure 29 Vinyl Chloride in Water Table Groundwater, Unrestricted Land Use Air Quality Protection Figure 30 Vinyl Chloride in Porewater Figure 31 uman and Ecological Conceptual Site Models Attachments Table A-1 - Summary of Site Soil Data Relative to Preliminary Cleanup Standards Table A-2 - Summary of Site Groundwater Data Relative to Preliminary Cleanup Standards V:\ Art Brass Plating\W4 oint Deliverable\SCM Memo\SCMmemo_.docx Page 9

10 TABLES

11 Table 1 - Summary of Critical Assumptions Site ydrogeology Groundwater flow to the west/southwest. Vertical gradient is downward between the Water Table and Shallow Intervals in the vicinity of the three facilities. Vertical gradient is upward between the Shallow and Intermediate Intervals in the well clusters close to the Waterway, west of East Marginal Way. igh tides result in transient localized groundwater flow gradient reversal near Waterway, although the time-averaged net groundwater flow direction is still toward the Waterway. The relatively dense saline water wedge that occurs in and below the Waterway results in an upward gradient of groundwater discharge into the river. Land Use Mixed land use throughout Site. Facility properties are industrial land use. Source Areas Releases from ABP, BDC, and CI are located west of 4th Avenue South. PSC source located east of 4th Avenue South contributes via groundwater migration. Contaminant Nature and Extent CVOCs are undergoing anaerobic reductive dechlorination in the all three groundwater intervals. Nature and extent maps illustrate lateral and vertical extent: - Soil figures exclude BDC data collected prior to excavation interim action (pre-2009 data excluded). - Groundwater figures use most recent well data and probe data for qualitative purposes. Pre-BDC interim action probe data excluded. In, plating metals attenuation is occurring in aquifer. Mechanisms being assessed separately in RI Data Gaps and Supplemental Work Plan for. Other metals (iron and manganese) are an area wide phenomena in groundwater intervals reflecting background conditions. Aspect Consulting 10/10/2014 V:\ Art Brass Plating\W4 oint Deliverable\SCM Memo\Tables\Tbl1_CriticalAssumptions_Draft.xlsx Table 1 Page 1 of 1

12 Table 2 Summary of Preliminary Cleanup Levels Farallon PN: Puget Sound Background Concentrations for Metals Soil Cleanup Level Protective of Direct Contact Pathway (Unrestricted Land Use) 1 Soil Cleanup Level Protective of Direct Contact Pathway (Industrial Land Use) 1 Soil Cleanup Level Protective of Air Quality based on Protection of Groundwater as Potable Drinking Water 2 Soil Cleanup Level Protective of Groundwater Concentrations Protective of Surface Water Quality 3 Groundwater Cleanup Level Protective of Air Quality Water Table Zone (Unrestricted Land Use) 4 Groundwater Cleanup Level Protective of Air Quality Water Table Zone (Industrial Land Use) 4 Air Cleanup Level Protective of Inhalation Pathway (Unrestricted Land Use) 1 Groundwater Cleanup Air Cleanup Level Protective Surface Water Cleanup Surface Water Cleanup Carcinogen or Level Protective of Surface Water 5 of Inhalation Pathway (Industrial Land Use) 1 Level Protective of uman ealth 6 Level Protective of Marine Environmnent 6 Sediment Cleanup Level 7 Constituent of Concern Non-Carcinogen (Milligrams/kilogram) (Micrograms/liter) (Micrograms/cubic meter) (Micrograms/liter) (Milligrams/kilogram) Tetrachloroethene Carcinogen Not Applicable , Not Researched To be determined 9 Trichloroethene Carcinogen Not Applicable 12 1, Not Researched To be determined cis-1,2-dichloroethene Non-Carcinogen Not Applicable 160 7,000 Not Applicable Not Applicable Not Researched 10 Not Researched Not Researched Not Researched Not Researched Not Researched Not Researched Not Researched trans-1,2-dichloroethene Non-Carcinogen Not Applicable 1,600 70, ,224 10, ,000 Not Researched To be determined 1,1-Dichloroethene Non-Carcinogen Not Applicable 4, , ,176 7, ,100 Not Researched To be determined Vinyl chloride Carcinogen Not Applicable Not Researched To be determined 1,4-Dioxane Carcinogen Not Applicable 10 1, ,551 25, Not Researched To be determined Arsenic Carcinogen Not Applicable Not Applicable Not Applicable 0.14 Not Applicable Not Applicable To be determined To be determined Not Applicable Barium Non-Carcinogen Not Researched 16, ,000 Not Applicable Not Applicable Not Applicable Not Applicable 4 Not Applicable Not Applicable To be determined To be determined Not Applicable Cadmium Non-Carcinogen ,500 Not Applicable 1.2 Not Applicable Not Applicable 8.8 Not Applicable Not Applicable To be determined To be determined Not Applicable Copper Non-Carcinogen 36 3, ,000 Not Applicable 1.1 Not Applicable Not Applicable 2.4 Not Applicable Not Applicable To be determined To be determined Not Applicable Iron Non-Carcinogen 58,700 58,700 2,450,000 Not Applicable Not Applicable Not Applicable Not Applicable Not Researched Not Applicable Not Applicable To be determined To be determined Not Applicable Manganese Non-Carcinogen 1,200 11, ,000 Not Applicable Not Applicable Not Applicable Not Applicable 100 Not Applicable Not Applicable To be determined To be determined Not Applicable Nickel Non-Carcinogen 48 1,600 70,000 Not Applicable 11 Not Applicable Not Applicable 8.2 Not Applicable Not Applicable To be determined To be determined Not Applicable Zinc Non-Carcinogen 85 24,000 1,050,000 Not Applicable 101 Not Applicable Not Applicable 81 Not Applicable Not Applicable To be determined To be determined Not Applicable NOTES: Preliminary cleanup levels presented represent the most stringent cleanup levels for the constituent of concern listed in the media indicated. 1 Cleanup level is based on standard Washington State Model Toxics Control Act Cleanup Regulation (MTCA) Method B (unrestricted land use) or Method C (industrial land use) values from the Cleanup and Risk Calculations tables (CLARC). 2 Soil cleanup levels for protection of air quality are preliminary values only. Values are calculated using MTCA Equation where the potable Method B groundwater cleanup level was used as Cw. Concentrations of hazardous substances in soil that meet the potable groundwater protection standard currently are considered sufficiently protective of the air pathway for unrestricted and industrial land uses. 3 Soil cleanup levels for protection of surface water quality are preliminary values only. Values are calculated using MTCA Equation where the groundwater cleanup level protective of surface water in this table was used as Cw. 4 Groundwater cleanup levels protective of the air pathway for unrestricted land use (residential and commercial sites) and industrial land use were derived using the following equation: Gwcul = Aircul/GIVF. 5 Various criteria were reviewed in the evaluation of the selected preliminary cleanup levels, including: - Washington State Model Toxics Control Act Cleanup Regulation (MTCA) Cleanup Levels and Risk Calculation standard values; - MTCA Method B Modified values based on Asian Pacific Island (API) Exposure scenarios for the consumption of fish for the groundwater-to-surface water pathway using equation 730-2; - The U.S. Environmental Protection Agency (EPA) Region 10 Final Feasibility Study for the Lower Duwamish Waterway dated October 31, 2012 and Proposed Plan for the Lower Duwamish Waterway Superfund Site dated February 28, 2013: and - The Fox Avenue Site Final Cleanup Action Plan completed in The most stringent cleanup level was retained as the selected preliminary cleanup level. The listed zinc value is Washington Administrative Code (WAC) A, Marine Surface Water Quality Criteria - Chronic as listed in the Final Feasibility study for the Lower Duwamish Waterway. This is more stringent than the Freshwater Surface Water Quality Criteria Acute and Chronic (110 and 100 micrograms per liter, respectively). 6 Surface water preliminary cleanup levels were derived using the same criteria as groundwater. uman health and marine aquatic ecologic receptors were considered. The most stringent exposure pathway for human health receptors are for consumption of fish. Marine receptor values for the organic constituents of concern are not researched whereas inorganic constituents of concern marine rather than freshwater values are listed based on likely conditions in the portion of the Lower Duwamish Waterway where groundwater may impact surface water. 7 Sediment cleanup levels are not established at this time since this medium has not been confirmed to be affected by groundwater discharge to surface water. Sediment cleanup levels will be established if confirmed and will be determined in accordance with WAC , the Sediment Management Standards. 8 Not Applicable is used where the constituent of concern will not affect the medium of potential concern due to an incomplete pathway or no pertinent standard exists. 9 To be determined denotes that a constituent of concern has either not been confirmed in a medium of concern or additional data are being collected during completion of the Feasibility Study to derived cleanup levels. Cleanup levels will be determined prior to completion of the Feasibility Study where appropriate and will consider the relevant regulatory criteria at that time. 10 Not Researched denotes that no regulatory standards or toxicity information are available for the constituent of concern to derive a cleanup level for the medium of potential concern. Preliminary Cleanup Levels V:\ Art Brass Plating\W4 oint Deliverable\SCM Memo\Tables\Tbl2_Prelim Cleanup Standards.xlsx 1 of 1

13 FIGURES

14 2Nd Ave S ELLOGG ISLAND TERMINAL 108 Diagonal Ave S DUWAMIS WATERWAY TERMINAL 115 «99 E Marginal Way S Ohio Ave S Ohio Ave S «99 Colorado Ave S SITE UNIT #1 (SU1) S Fidalgo St S Alaska St S udson St Utah Ave S SLIP #2 E Marginal Way S 1St Ave S Denver Ave S S Dawson St S Bennett St S Brandon St S Lucile St S Findlay St S Orcas St S Mead St S Fidalgo St 3Rd Ave S SITE UNIT #2 (SU2) 4Th Ave S 4Th Ave S 5Th Ave S S Front St 6Th Ave S Art Brass Plating Denver Ave S Blaser Die Casting Capital Industries 6Th Ave S S Fidalgo St S omer St S Orcas St S Michigan St Carleton Ave S Corson Ave S 5 GEORGETOWN Corson Ave S Airport Way S Philip Services Corporation Flora Ave S Ellis Ave S GIS Path: T:\projects_8\Artbrass\FS\Delivered\DataGapsWP2014\Fig 1 Site Diagram.mxd Coordinate System: NAD83 ARN Washington North Date Saved: 3/27/2014 User: pwittman Print Date: 10/10/2014 SLIP #3 E Marginal Way S 0 1,000 2,000 yrtle St ^ PROECT LOCATION «509 «99 Site Diagram MAR-2014 PROECT NO. REV FIGURE: 1

15 S S S S S Waste Storage Storage Maintenance Shed ALLEY S S Gas Oven Elect. Oven 3RD AVE S S S S S Office Bath Under Stairs Storage Polishing Former TCE Degreaser No. 1 Fire ydrant Water Meter S Storage Water Treatment Area Shipping Plating Area Storage Containment Berm Time Saver Room S S S Former TCE Degreaser No. 2 Door Way Parking Lot S Parts Washer Powder Coat Area Office Powder Storage Under Stairs Bumper Storage S S S S. FINDLAY ST Bath Storage Bumper Repair Bumper Repair Bath Elect. Panels Lunch Room S S S S S S S S S S S S S S S S S S S S S S S S S S S S Legend S S Approximate Property Boundary Catch Basin Sewer Line (Combined) N Art Brass Plating Facility Map Vapor Degreaser Location Corrugated Metal Pipe (Sewer Retention) PROECT NO. P/LAL REV SCC 2

16 :\ANET\0504 BlaserDieCasting\GIS\mxds\SiteDiagram_2014.mxd Office Space 3RD AVE S Warehouse/Manufacturing Space Blaser Die Casting 4T AVE S 1996 Addition Shed Sewer/Drainage Mainlines Drainage & Wastewater Side Sewers/Laterals Interior Walls Soil Excavation Extent Figure 3 Blaser Die Casting Facility Map Parcels Buildings ± Blaser Parcel 0 40

17 ORCAS FACILITY NORTWEST SALES GROUP STONE CRAFT CITY LIGT ELECTRICAL SUPPLY MARTIN SIGN FABRICATION SINGLE FAMILY RESIDENCE 2nd AVENUE SOUT COMMERCIAL BUILDING MEAD BUILDING 3rd AVENUE SOUT CAPITAL CONTAINER YARD 4th AVENUE SOUT SOUT MEAD STREET COMMERCIAL BUILDING PLANT 2 CANOPY COMMERCIAL BUILDING PLANT 5 PLANT 1 PLANT 2 PLANT 3 PLANT 4 COMMERCIAL BUILDING PLANT 4 CANOPY COMMERCIAL BUILDING SOUT FIDALGO STREET 1st AVENUE SOUT OFFICE OLYMPIC MEDICAL WAREOUSE MOBILE CRANE COMPANY LEGEND GULL INDUSTRIES BUILDING FIGURE 4 CAPITAL PROPERTY MONITORING WELL BY FARALLON (FEBRUARY 2006)

18 UP-38 PSC-CG PSC-R15 PSC-139-DP PSC-X20 PSC-CG PSC-N11 PSC-412L-GW2 PSC-412L-GW1 PSC-CS-402L-GW1 O IO AV E S PSC-CG-143-WT PSC-X23 PSC-P17 PSC-CG PSC-CG PSC-CG-138-WT PSC-CS-122F-GW1 PSC-P15 SP-33 SP-14 PSC-T20 MW-5 AS-15 PSC-412L MW-6 MW-6-30 PSC-CG PSC-CG PSC-R580L-GW1 PSC-580L-GW1 PSC-9 PSC-CG-130-WT PSC-10 5T AVE S ART BRASS 4T AVE S UTA AVE S PSC-CG-116-WT PSC-CG PSC-CG PSC-CG PSC-CG-113-I PSC-CG-122-WT PSC-CG PSC-CG-158-WT PSC-CG-155-WT PSC-CG-146-WT 1-D 1-I PSC-CG PSC-CG PSC-CG D PSC-CG-118-WT 104-I PSC-CG S S-1 PSC-CG S-1 PSC-CG-147-WT PSC-CG UP-36 PSC-CG-106-D PSC-CG-106-I PSC-CG-106-WT PSC-CG-156-WT PSC-CG S-1 PSC-CG PSC-CG-157-WT UP-35 PSC-CG-150-WT PSC-CG-149-WT 103-S I PSC-CG-124-WT PSC-CG PSC-CG S-2 UP-34 5-I 5-S S I 102-D DC-P09 PSC GW1 PSC GW2 DC-P02 PSC GW3 PSC-CG-126-WT PSC GW4 3RD RG IN AL W PSC-CG PSC-CG PSC-CG-127-WT AVE S AY S UP-37 1-S-1 PSC-CG PSC-CG-128-WT E MA PSC-I8 PSC-CG PSC-CG PSC-CG-115-WT PSC-CG SPO-7 PSC GW1 MW-7 PSC-214F-GW1 PMW-1 AS-3 SP-4 AS-20 SPO-46 MW-15 PSC-L13 MW-2 SP-13 MW-9 MW-3-50 MW-1 SPO-5 MW-8-30 MW-4 MW-3-30 SP-7 MW-8-70 SP-15 PSC GW1 DC-P03 MW-3 PSC-L14 MW-8 PSC GW1 PSC-12 SPO-1 SPO-15 PSC GW1 MW-16 SPO-3 SPO-4 PSC-N15 MW-14 MW-27 SP-29 PSC-CG MW SPO-38 SPO-52 PSC-217F-GW1 PSC GW1 PSC-X28 SPO-14 SPO-8 MW SPO-37 SPO-9 PSC-226O-GW1 PSC-15 B-2 PSC-I13 PSC-R22 SPO-36 MW PSC-CG PSC-L18 SPO-16 PSC-3080-GW1 PSC-14 MW PSC-CG-142-WT PSC-O19 MW PSC GW4 PSC-404O PSC-CG PSC-CG SPO-13 SPO-11 PSC-2220-GW1 STG-GP-9 AB-CG MW-11 PSC-412O PSC GW5 PSC-CG-131-WT W4-1 SPO-29 SPO-31 BDC PSC-16 B-1 DC-P05 PSC-406O SPO-47 PSC-V31 SPO-10 BDC PSC-211O-GW1 BDC-4-WT PSC-S24 PSC GW3 SPO-28 SPO-30 SPO-34 S ORCAS ST PSC GW6 SPO-39 SPO-35 PGG-33B MW-10 SPO-27 PGG-5 DC-P04 PSC-I17 SPO-33 DC-P06 SPO-12 SPO-17 BDC-1-WT PSC-M20 PSC-F13 DC-P10 SPO-32 SPO-26 PSC-212M-GW1 PSC GW2 SPO-21 MW PSC GW7 SPO-25 SPO-49 BDC-2-WT PGG-34 SPO-48 SPO-24 PSC GW9 MW PSC GW1 PGG-32 BDC-9 PGG-31 PSC GW1 SPO-18 DC-P01 PSC-CG MW SPO-23 PGG-39 PSC GW8 PSC GW1 MW PSC GW6 PSC-CG-134-WT SPO-19 PSC-17 PSC-21 SPO-22 PSC-19 BDC-3-60 SPO-40 PSC-CS-134M-GW1 CI-B17 PGG-27 BDC-3-WT BDC BDC-3-40 DC-P07 PSC-P26 W4-2 PSC-SG-12 PSC-G18 STG-VAS-4 CG BDC-11-WT CI-8-40 MW MW CI-B28 BDC CG CI-8-60 PSC-F16 BDC MW MW STG-CVAS-1 CG CI-MW-8 PGG-28 MW MW PSC-CG-136 CI-B16 CI-MW-5 SPO-50 PSC-23 PSC-CG STG-VAS-2 MW BDC-6-30 SPO-41 CI-MW-2 MW PGG-29 PSC-CG-136-WT CI-MW-6 PSC-CG-137-WT STG-GP-1 CI-B10 STG-VAS-5 BDC-6-WT STG-GP-4 CI-MW-1-40 PSC-CG PSC-CG ST STG-CVAS-2 CI-MW-1-WT STG-GP-8 BDC-6-60 LG O A CI D I PSC-CG-141-WT PGG-30 CI-MW-1-60 STG-VAS-6 S F CI-MW-3 PSC-CG CI-B18 PSC-23 CI-B14 CI-MW-4 CI-B15 CI-B06 STG-SVAS-1 PSC-I22 CI-B07 PSC-21 CI-7-60 STG-VAS-3 PSC-L30 PSC-Q17 CI-B12 CI-B25 PSC GW1 PSC-CG CI-MW-7 STG-VAS-7 PSC-F20 SPO-51 CI-B27 SPO-42 CI-7-40 CI-B13 PSC-Q32-E PSC-Q32-D PSC-Q32-A STG-GP-5 CI CI-B26 STG-GP-6 CI-9-40 PSC-Q32-G PSC-CG-140-WT CI PSC-B15 S FID ALG O ST CI-9-WT PSC-S34 PSC-Q32-C CI-B11 AB-CG CI CI-9-70 STG-GP-7 CI-10-WT PSC-CG PSC-Q32-B MW-24 PSC-28 CI PSC-Q32 PSC-Q32-F PSC-CG CI-B09 MW CI-B08 CI-B19 MW SPO-44 MW-13 PSC-580L-GW PSC-M13 MW-12 SP-5 PSC-507B PSC-521B-GW PSC-CG PSC-8 PSC-M9 PSC-Y26 PSC-CG PSC-CG-129-WT PSC-CG-153-WT PSC-CG PSC-CG-154-WT (IG BLASER PSC GW5 WA DC-P08 Y 99 ) PSC-CG-132-WT PSC-CG MW MW SPO-45 PSC-P36 MW MW PSC-NE-D21 PSC-31 Si Si te te U Un n i t it # # 0# 0 # 0# 0 0# # 0# # 0 # 0 # # # # 0# 0 # 0# 0 # 0# 0 # 0 # # # 00 0 # 0# CI-B22 CI-12-WT CI CI Exploration Locations Symbol (Exploration Type) CI-14-WT CI CI Monitoring Well CI-B23 CI-B20 PSC-CG CI-13-WT CI # 0 Soil Boring/Probe Porewater Color (Exploration Sampler) CI-B21 Art Brass Plating CI CI CI PSC-A24 Blaser Die Casting Capital Industries Philip Services Corporation Other Companies PSC-39 Site Unit Boundaries CI-B Building Outlines (as presented on other figures) Building on Subject Property PSC-F33 PSC-G33 PSC-XX Exploration Location Map A blue halo indicates multiple parties sampled from one location PRO ECT N O. RE VISED --- 5

19 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S Trichloroethene (TCE) Soil Sample Locations Detected at > 10x CUL Detected Above CUL Detected Below CUL Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface) alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The Soil Cleanup Level Protective of the Direct Contact Pathway (Unrestricted Land Use) for Trichloroethene (TCE) is 12 mg/kg TCE in Vadose Soil Direct Contact Pathway, Unrestricted Land Use GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 06 TCE in Vadose Soil - Direct Contact - Unrestricted Land Use.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 PROECT NO. REV 6

20 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S Tetrachloroethene (PCE) Soil Sample Locations Detected at > 10x Cleanup Level Detected Above Cleanup Level Detected Below Cleanup Level Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface). alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The Tetrachloroethene (PCE) Soil Cleanup Level for the Protection of Surface Water Quality is 0.05 mg/kg GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 07 PCE in Vadose Soil - SW Protection.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 PCE in Vadose Soil Surface Water Protection PROECT NO. REV 7

21 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S Trichloroethene (TCE) Soil Sample Locations Detected at > 10x Cleanup Level Detected Above Cleanup Level Detected Below Cleanup Level Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface). alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The Trichloroethene (TCE) Soil Cleanup Level for the Protection of Surface Water Quality is 0.15 mg/kg GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 08 TCE in Vadose Soil - SW Protection.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 TCE in Vadose Soil Surface Water Protection PROECT NO. REV 8

22 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S Vinyl Chloride Soil Sample Locations Detected at > 10x Cleanup Level Detected Above Cleanup Level Detected Below Cleanup Level Not Detected. Reporting Limit Above CUL. Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface). alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The Vinyl Chloride Soil Cleanup Level for the Protection of Surface Water Quality is mg/kg GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 09 VC in Vadose Soil - SW Protection.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 Vinyl Chloride in Vadose Soil Surface Water Protection PROECT NO. REV 9

23 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S Copper Soil Sample Locations Detected at > 10x Cleanup Level Detected Above Cleanup Level Detected Below Cleanup Level Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface). alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The Copper Soil Cleanup Level for the Protection of Surface Water Quality (based on the Puget Sound Soil Background Concentration) is 36 mg/kg GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 10 Copper in Vadose Soil - SW Protection.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 Copper in Vadose Soil Surface Water Protection PROECT NO. REV 10

24 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S Nickel Soil Sample Locations Detected at > 10x Cleanup Level Detected Above Cleanup Level Detected Below Cleanup Level Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface). alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The Nickel Soil Cleanup Level for the Protection of Surface Water Quality (based on the Puget Sound Soil Background Concentration) is 48 mg/kg GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 11 Nickel in Vadose Soil - SW Protection.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 Nickel in Vadose Soil Surface Water Protection PROECT NO. REV 11

25 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S Zinc Soil Sample Locations Detected at > 10x Cleanup Level Detected Above Cleanup Level Detected Below Cleanup Level Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface). alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The Zinc Soil Cleanup Level for the Protection of Surface Water Quality is 101 mg/kg GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 12 Zinc in Vadose Soil - SW Protection.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 Zinc in Vadose Soil Surface Water Protection PROECT NO. REV 12

26 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S 1,4-Dioxane Soil Sample Locations Detected at > 10x Cleanup Level Detected Above Cleanup Level Detected Below Cleanup Level Not Detected. Reporting Limit Above CUL. Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface). alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The 1,4-Dioxane Soil Cleanup Level for the Protection of Surface Water Quality is 0.32 mg/kg GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 13 14Dioxane in Vadose Soil - SW Protection.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 1,4-Dioxane in Vadose Soil Surface Water Protection PROECT NO. REV 13

27 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S Tetrachloroethene (PCE) Soil Sample Locations Detected at > 10x CUL Detected Above CUL Detected Below CUL Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface) alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The Tetrachloroethene (PCE) Soil Cleanup Level Protective of Air Quality (based on Protection of Groundwater as Potable Drinking Water) is 0.08 mg/kg GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 14 PCE in Vadose Soil - Protection or Air Quality.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 PCE in Vadose Soil Protection of Air Quality PROECT NO. REV 14

28 E MARGINAL WAY S (WY 99) 3RD AVE S 4TAVE S Trichloroethene (TCE) Soil Sample Locations Detected at > 10x CUL Detected Above CUL Detected Below CUL Not Detected Data shown on this map reflects the maximum concentration detected at that soil sample location in the vadose zone (0 to 8 ft. below ground surface) alf-foot Water Table Groundwater Elevation Contours from August, 2012 Site-Wide Monitoring Event The Trichloroethene (TCE) Soil Cleanup Level Protective of Air Quality (based on Protection of Groundwater as Potable Drinking Water) is 0.03 mg/kg GIS Path: T:\projects_8\Artbrass\FS\Delivered\SCM_Memo_101014\Fig 15 TCE in Vadose Soil - Protection or Air Quality.mxd Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Date Saved: 10/10/2014 User: pwittman Print Date: 10/10/2014 TCE in Vadose Soil Protection of Air Quality PROECT NO. REV 15