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1 Ile 28 October 2005 AGE-NC Project No 95-0130 ' Page 4 of 13 ' 2 4 1 GROUND WATER ELEVATION AND GRADIENT The measured depths to ground water from the purged wells were between 41 99 and 44 84 feet ' below the top of the well casings Ground water elevations were calculated to be between 26 44 feet (MW-1)and 28 62 feet(MW-6B)below mean sea level (MSL) Generally, ground water elevation at the site increased an average of 1 72 feet between the March 2005 and the June 2005 ground water ' monitoring events First zone (35 to 55 feet) ground water flow direction at the Top Filling Station was inferred to be towards the east-northeast at an approximate gradient of 0 02 ft/ft, Second zone (55 to 85 feet bsg)ground water flow direction at the Top Filling Station was inferred to be towards ' the east-northeast at a gradient of 0 003 ft/ft or less The First and Second zone ground water elevation data collected during the June 2005 ground water monitoring event is depicted on Figures 3 and 4, respectively I 2 4 2 LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES ' On 06 June 2005, a total of fifteen ground water samples were submitted to CTEL,a DHS-certified laboratory, for the analysis referenced in Section 2 3 TPH-g was detected from wells MW-3 MW-5 MW-6 (B-E), MW-7 B-D MW-8 VW-1 I VW-2A and VW-3A at concentrations as high as 160,000 micrograms per liter(µg/l)in the samples collected from wells MW-713 and VW-IC The estimated extent of First Zone (between 35 and 55 feet bsg) and Second Zone (between 55 and 80 feet bsg) dissolved TPH-g are depicted in Figures 5 Iand 7, respectively Benzene was detected from wells MW-3,MW-6(B-E),MW-7(B-D),VW-I C,VW-2A and VW-3A at concentrations as high as 48,000 µg/1 (MW-7B) Other BTEX compounds were detected in the above monitoring well samples at concentrations as high as 49,000 µg/1 toluene, 3,900 µg/1 ethylbenzene and 18,200 µg/l from VW-I C MTBE was detected in ground water samples collected from wells MW-3,MW-6 (B-D), MW-713, VW-IC, VW-2A and VW-3A at concentrations as high as 3,200 µg/1 (MW-6B) The estimated Iextent of First Zone and Second Zone dissolved MTBE are depicted in Figures 6 and 8,respectively 1,2-DCA was detected in ground water samples collected from wells MW-6 (B-D),MW-7 (B-D), MW-8,VW-1C, VW-2A and VW-3A at concentrations as high as 390 µg/l (MW-6B), TAME was detected in ground water samples collected from wells MW-6(B-D),MW-7(B-D),VW-I C,VW-2A and VW-3A at concentrations as high as 750 µg/1 (MW-6B) No other fuel components were detected in the round water samples Previous and current analytical p g p Yt Advanced GeoEnvironmentat,Inc I