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' 12 January 2005 AGE-NC Project No 97-0326 ' Page 9ofII Ground water elevations in the water-table (HUI) wells MW-1 through MW-3 and MW-7 ranged ' from 20 89 feet below mean sea level(MSL) in well MW-7 to 21 05 feet below MSL in well MW-3 (Table 2) Ground water flow in HUI (water table) was inferred to be radially Inward, ranging ' between a southeasterly flow direction on the west side of the site to a southwesterly direction on the east side of the site, the net ground water flow direction was south-southeast at an average gradient of 0 007 ft/ft Figure 6 illustrates the contoured ground water elevations as measured on 07 ' Apn12004 Utilizing multilevel wells MW-8 and MW-9,the vertical gradient between adjacent screen intervals in successively deeper hydrogeologic Intervals can be calculated by determining the difference between ground water elevations(dh)and dividing by the difference of the screen interval midpoints (dl) Downward vertical gradients were calculated between HUI and 14U2,HU2 and HU4,and HU4 and HU6 ' 35 ANALYTICAL RESULTS OF GROUND WATER SAMPLES Eleven ground water samples were collected and submitted for laboratory analysis for the '. constituents listed in Section 2 2 2, the analytical results are provided in Table 3 Based on the analytical results, each HU is characterized below ' HUI TPH-g was assessed in all ground water samples collected from HUI, at concentrations ranging from 470 micrograms per liter(µg/1) in sample MW-7 to 160,000 µg/1 in samples MW-2 and MW-3 (Figure 7), well MW-1 was not sampled due to the presence of free product BTEX compounds were detected in all HUI wells, at maximum concentrations of 34,000 µg/I ' benzene(MW-2),2 1,000 µg/I toluene(MW-9A),2,600 µg/1 ethylbenzene(MW-3)and 14,700 µg/1 xylenes (MW-3), only xylenes at a concentration of 3 4 µg/1 was detected in well MW-7 ' The fuel additive MTBE was detected in allHUI samples at concentrations ranging between 3 2 µg/1 in sample MW-7 to 680 µg/1 in sample MW-9A (Figure 8) In addition, 1,2-DCA was detected in sample MW-3 at 55 µg/i ' HU2 TPH-g and BTEX compounds were detected in samples MW-8B and MW-9B, the maximum concentrations were detected in sample MW-9B at 8,200 µg/1 TPH-g, 4,900 µg/l benzene, 43 µg/1 toluene, 59 µg/1 ethylbenzene and 260 µg/1 xylenes HU4 TPH-g and BTEX compounds were detected in samples MW-8C and MW-9C at maximum ' concentrations of 1,500 µg/1 TPH-g in sample MW-8C, and 550 µg/1 benzene, 62 µg11 toluene, 29 µg/l ethylbenzene and 88 µg/1 xylenes in sample MW-9C ' Advanced GeoEnvironmental,Inc