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r • 19 November 2002 AGE-NC Project No 01-0865 Page 3 of 5 3.0. FINDINGS Ground water elevation, flow direction, and gradient were determined from field data collected on 27 September 2002, the contaminant impact to ground water was quantified from the laboratory analytical data obtained from the sampling event 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 from the surveyed well casing elevation(Table 1) The depth to ground water ranged from 4 48 feet to 7 62 feet below the tops of the well casings Relative ground water elevations at the site ranged from 73 27 feet in well MW-3 to 79 27 feet in well MW-4 The ground water elevations at the site decreased 1 55 feet and 0 75 feet in wells MW-2 and MW-3, respectively and increased 2 96 feet in well MW-4 between the June 2002 and September 2002 sampling events The ground water flow direction on 27 September 2002 was calculated to be towards the southeast • under an average gradient of 0 06 feet/feet Figure 3 illustrates the contoured ground water elevations 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in the water samples collected from wells MW-2, MW-3 and MW-4 at concentrations of 110,000 micrograms per liter (µg/1), 20,000 µg/1 and 1,300 µg/l, respectively BTEX were detected in the sample collected from well MW-4 at concentrations of 0 µg/1 benzene, 6 2 µg11 toluene, 17 µg/1 ethylbenzene and 612 µg/1 total xylenes MTBE was detected in the samples collected from MW-2, MW-3 and MW-4 at concentrations of 81,000 µg/l, 19,000 µg/1 and 18 µg/l, respectively TBA was detected in the same water samples at concentrations of 2,700}ig/l,600µg/1 and 200µg/1,respectively TAME was detected in the samples collected from wells MW-2 and MW-3 at concentrations of 350 µg/1 and 90 µg11, respectively No other fuel additives were detected at or above laboratory reporting limits in the ground water samples Previous and current ground water analytical results are summarized on Table 2 The laboratory report(CTEL Lab I D No 0210-005-1 through 0210-005-3), QA/QC report and chain-of-custody form are included in Appendix C Advanced GeoEnvironmental,Inc