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Ground water samples collected from Wells MW-1 and MW-2 were ND for TPPH, BTEX, and MTBE Ground water samples collected from Wells MW-3 through MW-7 contained TPPH concentrations ranging from 1,300 to 31,000 parts per billion (ppb) and benzene concentrations ranging from 9 1 to 1,900 ppb Oxygenates were ND in ground water samples collected from Wells MW-3 and MW-5 through MW-7 MTBE and DIPS were detected in ground water samples collected from Well MW-4 at concentrations of 57 and 21 ppb, respectively DIPE was also detected in MW-1 at a concentration of 6 1 ppb Soil Stockpile Chemical Analytical Data: Soils generated during drilling were stockpiled on site Soil samples were collected and analyzed for constituents necessary to classify soils for disposal and meet landfill acceptance criteria The analyses included TPPH, BTEX, and total threshold limit concentration (TTLC) lead The laboratory analytical report is presented in Appendix C Based on the analytical data, the soils were classified as non-hazardous and disposed of by Manley and Sons Trucking, Inc , of Sacramento, California at Forward, Inc 's, Manteca, California landfill CONCLUSIONS Four soil borings (SB-1 through SB-4) and four ground water monitoring wells (MW-4 through MW-7) were installed in the vicinity of the subject site Lithology encountered in unsaturated soils consisted predominantly of very stiff to hard silts and clays and dense to very dense silty sands, clayey sands, and sands (SP) Lithology encountered in saturated soils consisted of dense to very dense silty sands, clayey sands, and sands and hard clays to the total explored depth of 71 5 fbg Ground water stabilized in the monitoring wells at depths ranging from 40 66 to 42 28 fbg Ground water elevation data indicate there is currently a narrow hydraulic ridge oriented north-south between Wells MW-2 and MW-3 Ground water flows westerly and southeasterly away from the ridge at an approximate hydraulic gradient of 0 01 toward the west and 0 009 toward the southeast Analytical results for soil samples indicate petroleum hydrocarbons do not extend vertically beneath depths of approximately 6 5 fbg in the vicinity of SB-1 (northeast of the southern product islands), 11 5 fbg in the vicinity of SB-3 (north of the northern product islands), and 26 5 fbg in the vicinity of SB-2 (north ,pf the southwestern product dispenser) Soil samples collected from SB-4 south of the northeastern product dispenser) contained TPPH concentrations ranging from ND to 1,200 ppm and extended vertically to ground_water Below ground water, the highest TPPH concentration was detected at a depth of approximately 56 5 fbg and decreased to ND at a depth of 66 5 fbg Soil sampling data for the newly installed wells (MW-4 through MW-7) did not identify TPPH in • unsaturated soils, thus suggesting a secondary source of petroleum hydrocarbons does not exist in these locations TPPH was detected at a depth of approximately 55 fbg at concentrations ranging from 3 3 to 92 ppm Benzene was detected in these samples at concentrations ranging from 0 37 to 374 5