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a 'NT: T;QNr. .�C s1Q� Y ORrYJRrTiCti Groundwater was encountered at approximately twenty-two feet below grade. Groundwater flows north-northeast with a gradient of 0,004 ft/ft (Figure 3). - Elevation data is contained in Table 1. _ As such, MW-3 is located directly downgradient of the gasoline tank field and PUMP islands, while MW-1 and MW-4 are located side gradient and MW-2 is located upgradient of the on-site petroleum hydrocarbon storage and transfer facilities, R44 is also located adjacent to a waste oil and motor oil tank field. 4.2 ANALYTICAL RESULTS Laboratory results for soil and water samples are summarized in Table 2 and 3 respectively. Copies of the signed laboratory reports are included in Appendix 0. . No free product was observed in any of the monitoring wells. TPH as gasoline were reported only in water samples in wells 1414-1 and MW-3, at concentrations of 0.140 ppm and 0.20 ppm respectively. Benzene concentrations in these two wells were 0.001 ppm and 0.033 ppm. Non-detectable levels of total petroleum hydrocarbons were reported in soils �- immediately above the water table in all boreholes. However, benzene and ethyl benzene were detected in the twenty foot depth soil samples from MW-3 at concentrations of 0.82 ppm and 0.43 ppm respectively. {. w Fecal coliform was not detected in the,graundwater samples in MW-1, MW-2, and MW-3, - u 5.0 COKLUSIONS AND RECOMMEHDATIOR The hydrogeology.,if the site consists inainly of clays wi"h..a thin four-foot thick sand layer at approximately 24 feet below grade. The groundwater gradient is 0.004 ft/ft to the north-northeast. Gasoline contaminants have been identified in the groundwater from wells MW-1 and W-3. This could indicate_a_gasoline_release._in...the-area-oF-the piping-- -- -- end/or the three gasoline tanks. The point of the release may be identified --- --- -- during the 'removal of the tanks which is already in the planning process. 5. ENG:7024/072390 7. s.4 .