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Also at the request of Mr. Kith, six samples were collected from the excavated soil, which had been stockpiled north of the excavation (Figure 2). These samples were collected a few inches below the surface of the stockpile by pushing a brass sample sleeve into the soil. All samples were shipped to McCampbell Analytical under chain-of-custody documentation. As directed by Mr. Kith, the samples were analyzed for Total Petroleum Hydrocarbons as gasoline, BTEX, total lead, and five gasoline oxygenates. The chain of custody and laboratory report are included in Appendix A. 5.0 BACKFILL AND SITE RESTORATION After the soil and water samples were collected, 5EMCO filled the excavation to a depth of 5 feet with pea gravel. Approximately 135 tons of gravel were used. Prior to placing the gravel, SEMCO placed three vertical PVC pipes into the excavation. The pipes, 8 inches it diameter and 10 feet in length, may be used in the future as conductor casings for drillholes through the pea gravel. After the conductor casings and gravel were emplaced, part of the stockpile of excavated soil was returned to the excavation and used to backfill it to grade. When backfilling was complete, the area was re-surfaced with asphalt. The remainder of the stockpile was hauled under non-hazardous manifest to Forward Landfill in Stockton for disposal. A copy of the load ticket will be forwarded to PHS/EHD when it is received from the landfill. 6.0 035 _W1AT—_3NS AND LA30RAT(DRY=+,SU)i—_S Gasoline sheen was present on the surface of the groundwater at the south end of the eastern tank, and moderate gasoline odors were noticeable during the tank removal. Odors were also present in the saturated, coarse-grained sand used as fill material within the tank excavation, and the fill was visibly discolored to greenish gray at the north end of the east tank. In contrast, the samples of the native soil collected from beneath the fill consisted of damp, blue-gray silty clay that appeared to be only slightly contaminated. Little or no evidence of contamination was observed in the samples collected from the stockpiled soil. The laboratory report has been summarized in Table 1. Gasoline was detected above the reporting limit of 1 mg/kg in all tank samples and 5 of 6 stockpile samples. Gasoline was also detected at elevated concentrations in both water samples. The laboratory reported that the chromatograms imply unaltered, fresh gasoline in the water samples and 3 of 4 tank samples. Benzene and other volatile aromatic compounds were also detected in the soil and water samples from the excavation. These components are responsible for the unaltered appearance of the gasoline on chromatograms. In contrast, these compounds are absent or present at low concentrations in the stockpile, giving the chromatograms the appearance of somewhat altered or degraded gasoline. 3