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. Groundwater Contour Map and Flow Gradient <br /> A groundwater contour map to a known datum was prepared for the data listed in Table i (see Figure 1) The <br /> groundwater flow direction was northerly under a calculated gradient of 0 0032, which is consistent with historic <br /> observed trends Overall groundwater levels appear to have declined roughly 0 2-0 3 feet from the previous quarter <br /> Chemical Analytical Methods and Results <br /> Seven groundwater samples were analyzed using EPA Methods 503018015, 602 and 8260 for Total Petroleum <br /> Hydrocarbons as Gasoline (TPHG), Benzene, Toluene, Ethylbenzene and Xylene (BTEX) and fuel oxygenates <br /> including Methyl-tert-butyl-ether (MTBE), Tert-Butyl Alcohol (TBA), Di-Isopropyl Ether (DIPE), Ethyl tert-butyl <br /> ether(ETRE), Tert-Amyl Methyl Ether TAME) The analytical results of the groundwater samples for this sampling <br /> event are attached and listed below in Table l (and Figures 2, 3 and 4, and historic data is presented in attached <br /> historic sampling data spreadsheet Table 2) <br /> Table 1 Current Quarter Groundwater Chemical Data(June 1,2004) <br /> Sample TPHG Ben Tol Eth 1 Xyl MTBE TBA DIPE ETBE TAME <br /> tigA UgA U0 Ug1l. ugn 1194 u u ugA u <br /> MW-1 ND ND ND ND ND ND ND ND i ND ND <br /> MW-2 1 15077 1 5 20 33 98 ND ND ND ND ND <br /> MW-3 NA NA NA NA NA NA NA NA NA NA <br /> • MW-4 ND ND ND ND ND ND ND ND ND ND <br /> MW-5 69 12 ND ND ND ND ND ND ND ND <br /> MW-6 710 ND ND ND ND ND ND ND ND ND <br /> MW-7 ND ND ND ND ND ND ND ND ND ND <br /> MW-8 ND ND ND ND ND ND ND ND ND ND <br /> MW-9 NA NA NA NA NA NA NA NA NA NA <br /> Equip ND ND ND ND ND ND ND ND ND ND <br /> Blank <br /> Lob ND ND ND Nil ND ND ND ND ND ND <br /> Method <br /> Blank <br /> ND-None detected ugA-micrograms per Mer Ben-Benzene Tol-Toluene Xyl-Xylene NA—No analysis <br /> Fuel Ox -Fuel Oxygenates by Method 8260 from Dec, 1997 forward Ethyl-Ethylbenzene <br /> 1,2 Dichloroethane and Ethylene Dibromide ND in all wells,these analyses discontinued in 2000 <br /> See historic data table for previous monitoring well sampling results Wells MW-3 and MW-9 removed for soil excavation work <br /> Discussion <br /> Groundwater flow direction is northerly at a flow gradient that is consistent with historically observed flow trends <br /> (see Figures 1 through 4) Groundwater levels have declined about 0 2-0 3 feet in wells since the last quarter <br /> Wells MW-3 and in MW-9 were not sampled since these wells had been abandoned prior to the soil excavation <br /> work Wright had removed contaminated soil in the vicinity of MW-3 and MW-9 between the two large pipelines <br /> crossing the site Soil was also removed from the area immediately downgradient of the former underground tank pit <br /> area In addition, dewatering operations necessary for the excavation removed contaminated groundwater that was <br /> • treated and discharged to a permitted outfall No separate phase product was observed at any well tlus quarter <br /> Page 2 of 4 <br />