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Analytical Results of Groundwater Samples The groundwater samples collected from monitoring well MW 1 contained TPHg concentrations of 850 ppb. Benzene was not detected, however toluene, ethylbenzene, and total xylenes were detected at concentrations of 5.2 ppb, 18 ppb, and 85 ppb, respectively. Total Lead and Oil and Grease concentrations were not detected in the groundwater samples. Analytical results are presented in Table 2, Analytical Results: Groundwater Samples. CONCLUSIONS The soil samples collected from borings SBI, SB2, and SB3 (located around the perimeter of the former UST pit) did not contain detectable concentrations of TPHg, B.TEX, or Oil and Grease, with the exception of the sample collected from SB 1 at 25.5 ft below ground surface which contained a concentration of 0.010 ppm total xylenes. The lateral extent of soil contamination has been defined. The soil samples collected from boring MW I contained TPHg and ethylbenzene concentrations between 20.5 ft and 30.5 ft below ground surface. Toluene was detected in the 10.5 ft sample and the 35.5 ft sample. Total xylenes were detected between 10.5 ft and 35.5 ft, and Oil and'Grease concentrations were detected between 10.5 ft and 30.5 ft below ground surface. Total lead was detected in all of the soil samples collected from borings SB 1, SB2, SB3, and MWI at concentrations ranging from 6 ppm to 16 ppm, with the exception of the 10.5 ft sample collected from MW 1 which contained 61 ppm. The concentrations detected are probably representative of background levels. Groundwater was first encountered during drilling of MW I at approximately 51 ft below . ground surface. The static depth to water in completed monitoring well MW 1 was 45.83 ft. The groundwater samples collected from MW 1 contained TPHg concentrations of 850 ppb, toluene at 5.2 ppb, ethylbenzene at 18 ppb, and total xylenes at 85 ppb. Total lead and Oil and Grease concentrations were not detected in the groundwater samples. • The vertical extent of soil contamination has been defined. The only significant areas of petroleum hydrocarbon impacted soil encountered during this investigation are between the depths of approximately 20.5 ft and 30.5 ft below ground surface in boring MW1 which is located in the center of the backfilled former UST pit. This impacted soil is approximately 20 ft above first encountered groundwater, which suggests that the petroleum hydrocarbon concentrations detected in the groundwater samples collected from MW I may possibly be from an off-site source. 10