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s 3.0 Subsurface Conditions Four borings were advanced at the locations shown on Figure 1 All borings were advanced to a depth of 415 feet below surface grade The borings revealed a sequence of clayey silt and sandy silt strata`�-These strata are weakly to moderately cemented between depths of about surface to 25 feet,with cementation strength declining with depth as a general rule The clayey silt and sandy silt may contain laterally discontinuous sand strata and interbeds contained in the silt strata Field evidence of contaminant presence(sheen, staining and odor) was not observed in any borehole Groundwater was encountered at depths of about 38 to 39 feet below surface grade occurring in clayey silt and sandy silt strata The groundwater appeared to be unconfined and entered boreholes slowly An estimate of groundwater flow direction (to a arbitrary datum) was attempted with field measurements from the temporaniy rased boreholes However the uncased boreholes were not open long enough for groundwater levels to equilibrate for adequate depth to groundwater measurements so a groundwater flow direction could not be plotted On the basis of the available borehole measurements and chemical data noted herein, the gradient appears to be flat and suggestive of a westerly flow direction 4.0 Chemical Analysis Fight soil samples and up to four groundwater samples were analyzed at a Kiff Analytical,Inc, a state certified analytical laboratory Samples wtested for the following; Total Petroleum Hydrocarbons as Gasoline (TPHG), Total Petroleum Hydrocarbons as Diesel (TPHD), Benzene (B),Toluene(T),Ethylbenzene (E), Xylene (X), and Volatile Organic Compounds (VOC) Methyl- . tert-butyl-ether (l1iPI'I3E), and fuel oxygenates tert-Amyl-Methyl-Ether (TAME), Ethyl-tert-Butyl- Ether (MTBE), Di-Isopropyl Ether (DIPS) and tert-Butyl Alcohol (TBE), and 1,2 Dichloroethane 0,2--DCA), 1,2 Dibromoethane (EDB), .and Ethanol and Methanol using EPA Methods 3550, 351018015, 5030, 8020 and 5030/8260B The data are presented in Tables 1 and 2 and the laboratory analytical reports are attached 5.0 Discussion Boring B-1 was advanced adjacent to the existing underground tank pit and dispensers and showed that contaminants were not detected in vadose soil profile samples The laboratory reported 1.1 milligrams per kilogram TPHD in soil sample B-2-7 @36 feet however the case narrative states that the result does not match the typical pattern for Diesel Borings B-2, B-3 and B-4 showed that contaminants were not detected in soil samples TPHG and Ethanol contaminants were detected in groundwater samples from Bonngs B-2 and B-3 located downgradient of the tank pit TPHD contaminants were detected in groundwater samples B-i adjacent to the tank pit However the laboratory reported TPHG in Borings 2 and 3 and TPHD in Borings 1,2 and 4 however the laboratory case narrative states that these results do not match the typical pattern for Gasoline and Diesel - Previous work by Wright sampled soil under the unleaded gasoline fill bucket that revealed 2,100 pans per billion (ppb) MTBE and 14,500 ppb TBA. Soil beneath the regular gasoline dispenser revealed 54 ppb MTBE The onginal leak observed at the dispenser appeared limited to the tank pit and tanks in vadose soil on the basis of this data A soil excavation in the area removed this • contaminated soil in January 2004 Page 3 of 6