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AWUGEPS Of51GNfP5iLC/1511L7AM5 At MW-9 the unsaturated zone (from the surface to 37 5 ft bgs) is composed of sandy silt and ' silty sand to about 22 ft bgs and clay to about 32 ft bgs The saturated zone is primarily composed of silty sand to about 53 ft bgs A clay lens is present at 40 to 42 ft bgs At BH-13 clay is present to about 17 ft bgs Sand and silty sand underlies the clay to about 45 ft bgs Below 45 ft clay is primarily present except for a sandy silt lens at 55 to 57 ft bgs 2.2.2 Analytical Results Table 2-1 presents the soil analytical results for MW-9 and BH-13 Analytical reports are ' presented in Appendix C Historical soil analytical results were presented in Results summary and Final Work Plan Amendment, 22 June 1995 Two soil samples collected from MW-9 were ' submitted for analysis (40 5 ft and 54 ft bgs) Both of these samples were collected from beneath the static water level of 37 5 ft bgs Petroleum hydrocarbons, including BTEX ' compounds were not detected in these samples Lead was detected at a maximum concentration of 8 mg/Kg in samples collected from MW-9 Seven soil samples collected from BH-13 were submitted for analysis Two of the samples were collected above the static water level At 25 5 ft bgs toluene (1,100 ug/Kg), ethylbenzene (5,100 ug/Kg), xylenes (29,000 ug/Kg), and TPH as gasoline (410 mg/Kg) were detected Hydrocarbons were not detected in the other sample collected above the static water level at 30 5 ' ft bgs Relatively high concentrations of hydrocarbons were detected below the static water level at 45 5 ft, 50 5, 55 5 ft, and 60 5 ft bgs The maximum concentrations of toluene (34,000 ug/Kg), ethylbenzene (13,000 ug/Kg), xylenes (66,000 ug/Kg), and TPH as gasoline (650 mg/Kg) were ' detected at 55 5 ft bgs The maximum concentration of benzene (37,000 ug/Kg) was detected at 45 5 ft bgs Hydrocarbon concentrations were significantly lower at 65 5 ft bgs The concentration of lead in samples collected from BH-13 ranged from 6 mg/Kg to 13 mg/Kg ' Table 2-2 presents the results of the grab groundwater sample collected from BH-13 and the quality assurance samples Relatively high concentrations of hydrocarbons were present in the grab groundwater sample Toluene and xylenes were detected in the equipment blank, however, since concentrations were low compared to the concentrations in soil samples the validity of the soil sample results is not in question Analytes were not detected in the ambient blank ' 7 ons,19%L 5FlneraoffnlSlC1S]C}ISA IST