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11 January 2006 AGE-NC Project No 95-0130 Page 11 of 14 • Ground water at the site was generally observed between 42 and 45 feet bsg and was above ' the screened intervals of wells MW-1 through MW-5, MW-6 (B-E), MW-7 (B-E),VW-1C, VW-2A and VW-3A (x a screened below ground water table), and may not yield samples ' fully representative of shallowest ground water conditions • Ground water flow direction within HU 1 (First Water Zone)was inferred to be towards the northeast at a gradient of 0 01 ft/ft (Figure 3), ground water flow direction within HU2 and ' HU3 (Second Water Zone) was inferred to be towards the east-southeast at a gradient of 0 01 fl/ft or less ' • Between January 1995 and August 2001, ground water elevations at the site generally increased from 44 feet to 23 feet below MSL, since August 2001 and present day, ground water elevations have generally fluctuated between 24 feet and 29 feet below MSL(Table 2) • The highest concentrations of dissolved TPH-g and BTEX were detected in samples collected from wells MW-7B (50-55 ft),VW-1C (48-63 ft) and VW-2A(43-63 ft) which is ' consistent with previous monitoring results (Table 3) TPH-g concentrations were detected as high as 160,000 µg/l from well MW-7B and benzene as high as 20,000 µg/1 from well MW-7B (Table 4) Additionally, the deepest detection of dissolved TPH-g and BTEX was ' in the sample collected from well MW-6E (137-142 feet) The approximate extent of dissolved TPH-g is depicted in Figures 5 and 7 • The highest concentrations of dissolved MTBE were detected in samples MW-6B and ' MW-7B at 2,600 µg/l and 1,000 µg/l, respectively, the approximate extent of dissolved MTBE is depicted in Figures 6 and 8 • The highest concentration of 1,2-DCA was detected in sample MW-7B at 190 µg/1, significant concentrations of 1,2-DCA were detected or have consistently been detected from wells MW-3, MW-6(B-D), MW-7(B-D), MW-8, VW-1B, VW-1C, VW-2A, VW-2B and ' VW-3A, indicating a significant 1,2-DCA-impact to ground water at the site • TAME was detected in ground water samples collected from wells MW-6 (B-E), MW-7 ' (B-D),VW-1C and VW-2A at concentrations as high as 57 4g/l (VW-1C) Thxs is the sixth consecutive occurrence that TAME has been detected in ground water samples collected from the site, with the exception of one detection of TAME in December 2003 and March 2003 in wells VW-2A and VW-3A, respectively • TBA and EDB were not detected in any of the analyzed water samples, however, they had ' been detected previously TBA had been detected In wells MWA, MW-2, MW-3, MW-5, VW-1 C,VW-2A,VW-2B and VW-3A, suggesting a minor TBA-impact to ground water at the site EDB had been detected from wells MW-7B, V W-1 B, V W-1 C and VW-2A at ' concentrations significantly above the DHS's Maximum Contaminant Level (MCL) in drinking water Advanced GeoEnvironmentnl,Inc