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14 February 2006 <br /> AGE-NC Project No 95-0141 <br /> Page 3 of 5 <br /> 3 1 GROUND WATER ELEVATION AND GRADIENT <br /> At the time of the November 2005 monitoring event,depths to ground water ranged from 20 68 feet <br /> to 21 96 feet below the tops of the well casings Ground water elevations at the site ranged from <br />' 10 92 feet below mean sea level (MSL)in well MW-12A to 11 71 feet below MSL in well MW-813 <br /> (Table 1) <br />' Wells MW-5, MW-7, MW-8A through MW-12A and EX-1 were used to determine ground water <br /> flow direction and gradient for shallow ground water The shallow ground water was inferred to flow <br /> generally toward the southeast, at an average gradient of 0 005 foot per foot (ft/ft) However, this <br /> quarter's data shows a range of groundwater flow gradients occurring onsite and at the adjacent <br /> Lopez property,at rates between 0 005 ft/ft and 0 080 ft/ft Figure 3 illustrates the contoured shallow <br />' ground water elevations as measured on 03 November 2005 <br /> Wells MW-6 and MW-8B through MW-12B were used to determine ground water flow direction <br />' and gradient for the deep ground water zone The deep ground water was inferred to flow generally <br /> towards the southeast, at a gradient ranging between 0 002 and 0 006 ft/ft Figure 4 illustrates the <br /> contoured deep ground water elevations as measured on 03 November 2005 <br /> 1 • <br /> 3 2 ANALYTICAL RESULTS FROM GROUND WATER SAMPLES <br />' The analytical results of the round water samples were as follows <br /> yt g p <br />' 0 TPH-g was detected in ground water samples collected from wells MW-3, MW-8B, <br /> MW-I IB and EX-1 at concentrations ranging from 200 micrograms per liter (µg/1) in <br />' MW-I IB to 79,000 µg/1 in EX-1 <br /> • Various BTEX compounds were detected in well samples MW-3, MW-5, MW-813, <br /> MW-11B, and EX-1 at concentrations as high as 8,000 µg/1 of benzene, 27,000 µg/1 of <br /> toluene, 3,700 µg/1 of ethylbenzene and 18,700 µg/1 of xylenes from well EX-1 <br /> • 1,2-DCA was detected in ground water samples collected from eight out of the fifteen wells <br />' Samples from wells MW-3, MW-6, MW-7, MW-8A/B, MW-913, MW-1113, and EX-1 <br /> showed concentrations of 1,2-DCA ranging from 5 8 µg/1 (MW-3) to 180 µg/1 (EX-1) <br /> TAME was detected in ground water samples from MW-8B and EX-I at concentrations of <br /> 37 µg/1 and 130 µg/1, respectively <br /> • EDB was detected in ground water sample EX-1 at a concentration of 53 µg/1 <br /> i <br /> • <br /> Advanced GeoEnvironmental,Inc <br />