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1 4_0 INTERPRETATION OF RESULTS As shown in Tablet, no hydrocarbon residues were found in groundwater at the site. No floating product(gasoline) was observed during sampling. The low concentrations of total lead found in the groundwater (0.0075 to 0.0082 mg/L) are believed to be background concentrations. As a result of drilling access restrictions and a lack of prior site specific groundwater gradient data, this study did not result in water quality data downgradient of the former tank site. In spite of the lack of downgradient data, the fact that no hydrocarbon compounds were detected in any of the wells, especially the former tank location well, suggests there is likely no detectable hydrocarbon impact to groundwater beneath the site. As wells MW-2 and MW-3 are both upgradient from the former tank location, the absence of hydrocarbons in these wells was not unexpeccted. The most significant result of this study is the fact that both rounds of sampling-revealed no detectable hydrocarbons in groundwater from MW-1 located directly in the former tank location. 5.0 FINDINGS AND RECOMMENDATIONS 5.1 Summary of Findinaa The following is a summary of the findings based on the field investigation, analytical results and interpretations: Three groundwater monitoring wells have been constructed on the site. r The groundwater flow direction is to the northwest'and the gradient magnitude is 0.0016 ftfft. r Based on`two separate rounds of sampling and analysis, it appears that no hydrocarbon residues are present in the groundwater beneath the former tank location. 5.2 Recommendations Based on the results of this study, WESTON believes that there is no observable hydrocarbon impact to the groundwater beneath the site. Therefore, WESTON recommends that no further work be done on the site. t,a - 9 -