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' 05 November 2005 AGE-NC Project No 97-0326 IPage 3 of 5 1 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION At the time of the September 2005 sampling event, depths to ground water ranged from 34 32 feet ' to 37 63 feet below the tops of the well casings First-encountered ground water was within the screen interval of wells MW-1 through MW-3, MW-7, MW-8A and MW-9A, these wells should yield samples representative of shallow ground water conditions(Table 1),ground water from deep- screened wells MW-8B-D and MW-9B-D should yield samples representative of deeper ground water conditions ' The elevation of ground water in each well was calculated by subtracting the depth to ground water from the casing elevations Ground water elevations ranged from 20 86 feet (MW-1) to 22 48 feet (MW-8D) below mean sea level (MSL) ' A ground water elevation map of first-encountered ground water is presented in Figure 3 First-encountered ground water was inferred to be flowing toward the south with a hydraulic gradient ' of 0 005 foot/foot(ft/ft)or less The flow direction is generally consistent with previous monitoring events ' 32 ANALYTICAL RESULTS OF GROUND WATER SAMPLES ' Twelve ground water samples were collected and submitted for laboratory analysis for the constituents listed in Section 2 2 (Table 2) The analytical results for each hydrogeologic unit is ' characterized below HU1 - TPH-g was detected in ground water samples collected in HU1 from wells MWA, MW-2, ' MW-3, MW-8A, and MW-9A at concentrations ranging from 2,300 micrograms per liter (µg11) in sample MW-8A to 95,000 µg/1 in sample MW-3 (Figure 4) ' BTEX compounds were detected in ground water samples collected in HUI from wells MW-1, MW-2, MW-3, MW-8A, and MW-9A at maximum concentrations of 25,000 µg/1 benzene, 6,000 µg/l ethylbenzene and 22,000 µg/1 xylenes in sample MW-3, and 17,000 µg/1 toluene in sample ' MW-9A The fuel additives MTBE and TAME were detected in ground water samples collected in HU 1 from ' wells MW-1,MW-2,MW-3,MW-8A,and MW-9A at concentrations ranging from 34 µg/l(MW-2) to 4,800µg/1(MW-9A)(Figure 5)and from 2 1 µg/1(MW-1)to 340(MW-3),respectively 1,2-DCA was detected in samples MW-1,MW-3, MW-8A,and MW-9A at a maximum concentration of 200 ' µg/1 (MW-3) ' Advanced CeoEnvironmental,Inc 1