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I - 10 27 September 2004 AGE-NC Project No 96-0263 1 Page 3 of 5 1 Total petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with EPA Method 5030/8015 Modified, • Benzene, toluene, ethylbenzene and total xylenes (BTEX) and methyl tertiary-butyl ether 1 (MTBE) in accordance with EPA Method 8 02 1, and • Fuel additives dl-isopropyl ether(DIPE), ethyl tertiary-butyl ether(ETBE), MTBE, tertiary- amyl methyl ether(TAME),tertiary butanol (TBA), 1,2-dichloroethane(1,2-DCA)and 1,2- dibromoethane (EDB) in accordance with EPA Method 8260B I 3.0 FINDINGS 1 Ground water elevation, flow direction, and gradient were determined from field data collected on 27 March 2004, the contaminant impact to ground water was quantified from the laboratory 1 analytical data 10 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION The elevation of ground water in each well was calculated by subtracting the depth to ground water 1 from the surveyed well casing elevations (Table 1) For the March 2004 sampling event, depths to ground water ranged from 7 25 feet to 8 35 feet below the tops of the well casings Ground water elevations at the site ranged from 28 52 feet above mean sea level(MSL)in well MW-9 to 29 41 feet 1 above MSL in well MW-1 The ground water flow direction was determined by contounng the ground water elevation data The ground water at the site was inferred to be flowing to the north-northwest at an average gradient of 0 005 foot/foot The ground water contours are depicted on Figure 3 Elevation data from deep- screened well MW-6(screened between 27 and 32 feet bsg)was not used to determine ground water flow direction 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in water samples MW-2, MW-4,MW-5 and MW-7 at concentrations ranging from 200 micrograms per liter(pg/1) in MW-4 to 6,300 µg/1 in MW-7 Benzene was detected in water samples MW-2,MW-4,MW-5,MW-7 and MW-9 at concentrations ranging from 5 8 gg/l in MW-9 to 79 pg/l in MW-7 Toluene was detected in sample MW-7 and MW-9 at concentrations of 24 and 3 2µg11, respectively Ethylbenzene was detected in samples Advanced GeoEnvironmental,Inc I