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i The monitor wells were last gauged in December 1993 and the depth to water ranged between 15 and 16 feet bgs The shallow groundwater beneath the site flows in an easterly direction with and Iestimated gradient of 0013 (Figure 4) Groundwater gauging data for November 4, 1992 and ' December 2, 1993 are presented in Table 1 ' 42 Soil Sampling Results Nine soil samples were collected and analyzed during the tank and product line removal activities ' Hydrocarbon impacted soil appears to be limited to the areas beneath the former 12,000 gallon UST at 460 parts per million (ppm) TPHg and the north pump island excavation at 13,000 ppm TPHg ' (Figure 5) Soil samples analyzed for total lead were below the laboratory detection limit EDB was detected in soil samples from the excavation at the east end of the 6,000 gallon UST and the north ' dispenser island excavation at levels of 0 0065 ppm, and 0 064 ppm respectively Laboratory reports are included in Appendix D 1 Toluene and EDB were not detected in any of the samples collected from the soil borings during the August 1992 and December 1993 investigations TPHg and xylenes were detected in soil samples collected from bonngs W2, W3, and W4 at relatively low concentrations (Figure 5) The sample collected from a depth of 10 5 feet in W4 was found to contain the highest concentration of ' hydrocarbon constituents, TPHg, ethylbenzene, and xylenes were reported at 290, 3 4 and 30 ppm, respectively Ethylbenzene was not detected in soil samples collected from W1 or W2, or from W5 ' through W7 Benzene was detected at a concentration of 0 0060 ppm in the sample from W3 collected at a depth interval of 14 0 to 14 5 feet The results of the soil boring analytical results are ' summarized in Table 3 Laboratory reports are included in Appendix D ' Soil investigation results indicate that the petroleum hydrocarbons in soil exist primarily in the pump island area and within the west end of the former UST tank pit The approximate lateral and vertical extent of petroleum hydrocarbons in soil is depicted in Figures 6 and 7, respectively C4 ACUR• 70C 1434 PAR 7 N0005-002-0k May 31 1994