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hydrocarbons in soil increased in the soil boring for MW-2 Th le collected from saturated soil at 50 feet bgs from MW-2 contained60 mg/k of TPH-as- asoline 4 5 mg/kg of ' benzene, 72 mg/kg of toluene, 26 mg/kg of ethylbenzene and 150 mg/kg of xylenes The vertical extent of impacted soil beneath the former UST excavation is defined on the basis of soil samples collected for analysis from the previously drilled soil boring B-1 The sod boring B-1 was drilled in August 1994 in close proximity to MW-2 The soil sample collected at 55 feet bgs from B-1 contained only trace concentrations of toluene (0 0056 mg/kg) and xylenes (0 018 mg/kg) and the soil sample collected at 60 feet from B-1 only contained trace concentrations of xylenes (0 017 mg/kg) Laterally, the extent of impacted soil appears to be limited to the footprint of the former UST excavation Soil samples collected from sod borings on the northeast (MW-1), northwest (MW-3), southwest (B-2) and southeast (B-3) of the former UST excavation did not contain significant concentrations of gasoline hydrocarbons The distribution and extent of impacted soil is illustrated in two cross-sections (Figures 5 and 6) Groundwater beneath and to the west of the former UST excavation is impacted by significant concentrations of gasoline hydrocarbons The highest concentrations of gasoline hydrocarbons were detected in the groundwater sample collected from MW-3 This sample contained 120,000 µg/I of TPH-as-gasoline, 7,800 µg/l of benzene, 64,000 µg11 of toluene, 4,300 µg/I of ethylbenzene and 28,000 pg/I of xylenes The groundwater sample collected from MW-2 contained 16,000 µg/l of TPH-as-gasoline, 1,300 �ig/l of benzene, 1,500 gg/l of toluene, 1,800 µg/l of ethylbenzene and 6,900 µg/l of xylenes The groundwater sample collected from MW-1 did not contain detectable ` concentrations of gasoline hydrocarbons The concentrations of TPH-as-gasoline and benzene are posted on Figure 7 . 11