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3.1.1 Soil Investigation/Remediation Activities ' All work conducted is focused on the goal of eventually obtaining closure for the tank area excavation and any other remedial excavation work which may be required onsite The following is a summary of the work completed on tasks associated with soils remediation during September and October 1992 Appendix C presents a detailed field report of this activity along with all related analytical reports ' In general, all work completed was preparatory work necessary for the installation of the planned SVE system Preparatory work included demolition and disposal of the gas station canopy structure, locating and capping fuel pipelines at the building foundation and removal of ' the fuel pipelines throughout the open areas of the site Sampling of the soil beneath the former fuel pipelines, in the tank excavation and in the existing soil stockpile was completed as shown on Figure 4 to evaluate the current presence of hydrocarbon compounds or lead Samples from ' the tank excavation area (a total of seven) were coded according to their location in the pit and their depth below the surface Samples N1, N2, S1 and S2 were collected from the excavation floor approximately 20 feet below surface grade and samples NW 1, NW2 and S W2 were taken ' from the excavation sidewalls (approximately 1'/2 feet into the wall) at 10 feet below grade Samples from the pipeline trenches (a total of five plus two confirmation samples) were coded ' as "PL" samples and were taken 11/2 feet below the bottom of the trenches Soil stockpile samples were coded "SP" and were taken from 11h feet below the surface of the stockpile at six locations approximately 4 feet above the surface grade Analysis for TPH-G and BTEX was conducted for all samples while total lead was analyzed only for the PL samples All samples were initially analyzed by a California certified mobil Iaboratory while two samples were also analyzed by a fixed base laboratory for confirmation of the mobile laboratory results Figure 4 shows the sampling locations, soil sample identification numbers and soil sample results of all samples taken during this phase of work As shown, sample S-2 was the only soil sample ' which contained elevated hydrocarbon concentrations, with 1,490 mg/Kg of TPH-G and 6 41 mg/Kg, 13 39 mg/Kg and 52 52 mg/Kg of toluene, ethylbenzene and xylene, respectively No benzene was detected in any of the soil samples No detectable concentrations of TPH-G or ' BTEX were found in the confirmation samples taken at locations PL-3 and PL-5 which confirmed the results of the mobile lab analyses Soil sampling was also conducted as part of the installation of three new monitor wells discussed in the next section of this report ,No detectable concentrations of TPH-G or BTEX compounds were found at any of the well installation sites ' 3.1.2 Groundwater Investigation Activities The previous groundwater investigation (installation of three monitor wells) was expanded under ' the current investigation program by the installation of three additional groundwater monitor wells, two on the site and one north of the site on West Lane (Figure 2) Each well was constructed of two-inch diameter PVC casing and screen to a total depth of approximately 107 feet with a screened interval from approximately 85 to 105 feet A detailed field report of the well installation procedure is presented in Appendix D SIKCIRPMAREC3QTR WP 8 11/13192