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i 3� 3.2 Groundwater Sample Results Table I indicates that there was no detectable hydrocarbon presence in Mill!-4 in either sampling round. There was, however, an indication of the-presence of coliform bacteria in the groundwater. This bacteria may have its source in the sewer line which is located approximately five:feet east of the well. This sample was collected in accord with EHD instruction to sample groundwater for coliform bacteria when a monitoring well is installed within 50 feet of a sewer line. The presence :of coliform bacteria is unrelated to the underground storage tank groundwater investigation at this site. 4.0 INTERPRETATION OF RESULTS 4.1 Soil Results The results of soil sampling conducted on this site indicate that there is at present no significant hydrocarbon' presence 4n the soil at the two locations sampled. Soil samples taken at the SBA and SB-3 locations would have shown hydrocarbon presence had there been hydrocarbons moving downgradient from the former tank location on the groundwater surface. The absence of hydrocarbon in SB-3 suggests that if hydrocarbons were present in groundwater in the tank pit(as indicated by previous groundwater sampling results)these i compounds have',naturaily biodegraded or have remained adsorbed by soil (clay)particles within the area..less than 8 feet from the tank pit location. The absence of significant hydrocarbons in SBA suggests that the fill material along the storm drain line west of the restaurant did not act as a conduit for hydrocarbon bearing groundwater. 4.2 Groundwater Results Groundwater sample results from two separate sampling rounds indicate that there is no detectable hydrocarbon presence in MW-4. Because MW-4 is directly downgradient from the former tank location, the lack of compound.presence indicates that it is unlikely that the groundwater beneath the site has been impacted by petroleum hydrocarbons. 5.0 FINDINGS AND RECOMMENDATIONS The results from soil samples SBA and SES-3, the results of two groundwater samples y from MWA and the results of two previous sampling rounds from MWA all strongly support,the interpretation that hydrocarbon presence is not an issue of concern at this site. For these reasons, WESTON recommends that no further investigative work be performed on the site and that the site be closed. • 1 5 -