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USEPA Test Method SW-846 procedure for composite soil sampling. The three soil samples collected from the soil stockpile were identified as STK-1/2, STK-3/4 and STK 5/6. The soil samples were placed in brass sleeves and preserved on ice and transported under chain of custody for analysis to West Laboratories, Davis, California. Three of these soil samples were reportedly analyzed for BTEX using USEPA Test Method 8020; TPH-g using USEPA Test Method 8015M; diesel and motor oil using USEPA Test Method 8015M. All analytical sample results were reported to contain petroleum hydrocarbon constituents below analytical method detection limits. The soil was subsequently spread on the property under direction of PHSEHD. No map is available from PHSEHD records review to show where the soil samples were collected from. Soil sample analytical laboratory results are presented in Table 3. Additional soil site assessment work was conducted on December 5 to 7, 1994 when Gregg In Situ Inc. completed a series of Cone Penetration Test(CPT) soil borings of the site and surrounding area. The CPT investigation consisted of 14 soil borings or"hydropunch" borings (Figure 6). These borings identified subsurface lithologic conditions encountered from the surface to a maximum depth of 60 feet bgs. Most of the CPT hydropunch soil borings were between 45 and 53 feet deep. The CPT data indicated that the majority of the site is underlain by alternating fine grained silt and clay beds up to several feet thick alternating with sand layers up to several feet thick. This stratigraphic sequence continues to a depth of about 60 feet bgs. No soil samples were submitted to analytical laboratory for analysis. Groundwater grab samples were collected from nine of the fourteen CPT soil borings and analyzed by Matrix Environmental Laboratories for BTEX using USEPA Test Method 602. Analytical laboratory results reportedly indicated a fairly widespread horizontal extent of volatile organic compounds in the groundwater(Figure 7). Analytical laboratory results from the groundwater grab samples collected from the CPT soil borings are tabulated in Table 4. Additional groundwater monitoring events were conducted during the 3rd and 4th quarter of 1994 by Dana Booth(Booth. 1994b, and 1994c). An expanded site assessment workplan was submitted to PHSEHD by Dana Booth in 1995 (Booth, 1995). A groundwater monitoring event that included analysis of water from the onsite monitoring wells occurred in 1997 (Booth, 1997). Subsurface investigations by Muir(2003, 2006 and 2008) drilled and completed an additional six groundwater monitoring wells (PT-MW4 to PT-MW9) (Figure 6). In support of this additional work eight additional soil borings were also drilled and sampled(Table 2). Three additional 2"- diameter groundwater wells were drilled and completed in 2008 (Table 2). Soil and groundwater samples collected from these wells indicated a minimum probable soil contaminant mass of about 9,900 cubic feet present between 15 and 45 feet bgs at the site and a groundwater petroleum hydrocarbon plume of approximately 25,000 square feet in extent. A workplan to conduct a soil vapor extraction (SVE) and air-sparge pilot test was submitted to PHSEHD in January, 2010 (Muir, 2010a). Two dual-nested Soil Vapor Extraction (SVE) wells, PT-SVEI and SVE2 were drilled and completed during May, 2010. These wells were Parmar\Site Assessment Workplan\02152018.wpd 6