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. 20 October 2004 AGE-NC Project No 95-0109 Page 3 of 5 • Volatile organic compounds (basic target list) in accordance with EPA Method 8260B The basic target list includes benzene, toluene, ethylbenzene and xylenes (BTEX), and the fuel additives di-isopropyl ether (DIPE), ethyl tertiary-butyl ether (ETBE), methyl tertiary-butyl ether (MTBE),tertiary-amyl methyl ether(TAME),tertiary butanol(TBA), 1,2-dichloroethane(1,2-DCA) and ethylene dibromide (EDB) 3.0 FINDINGS Ground water elevation and flow direction were inferred from the field data The petroleum hydrocarbon-impact to ground water was quantified by laboratory analysis of the ground water samples 3 1 GROUND WATER GRADIENT AND DIRECTION On 09 September 2004, the depth to ground water ranged from 57 10 feet to 62 25 feet below the tops of the well casings Ground water elevations at the site ranged from 3 20 feet below mean sea level (MSL) in well MW-5 to 8 47 feet below MSL in well MW-17 Ground water levels were within the screened intervals of water table wells MW-i through MW-14 and MW-16, but ranged from approximately 13 to 50 feet above the screened intervals of the deep-screened wells MW-15, MW-17,MW-18 and MW-19 Data from wells MW-1 through MW-5 were not used to infer ground water flow direction or gradient because these wells are screened at different intervals than the remaining wells The ground water for the well network was inferred to be flowing towards the south The ground water gradient ranged from approximately 0 002 ftlft on-site to 0 005 ft/ft off-site Figure 3 illustrates the contoured ground water elevations, historical ground water flow directions are summarized in Table 4 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in ground water samples from wells MW-8 and MW-9 at concentrations of 2,600 micrograms per liter (gg/l) in MW-8 and 1,700 µg/1 in MW-9 BTEX compounds were detected in the samples from the same wells at concentrations as high as 1 5 µg/1 benzene(MW-8), 4 0 µg/1 toluene (MW-8), 57 µg/l ethylbenzene (MW-9) and 240 µg/l total xylenes (MW-8) Advanced GeoEnvironmental,Inc