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' 27 February 2004 . AGE-NC Project No 95-0130 IPage 3 of 6 3.4 FINDINGS ' Ground water elevation flow direction and gradient were determined from field data collected on 10 November 2003 The contaminant impact to groundwater was quantified by laboratory analysis ' of water samples ' 3 1 GROUND WATER ELEVATION AND GRADIENT ' The depths to ground water from the purged wells were measured between 43 39 and 44 52 feet below the top of the well casings Ground water elevations were calculated to be between 27 27 (MW-6A) feet and 28 33 (MW-7E) feet below mean sea level (MSL) Generally, ground water elevation at the site decreased an average 0 77 feet between the August 2003 and the November 2003 ground water monitoring events First zone (between 35 and 55 feet) ground water flow direction at the Top Filling Station was Inferred to be towards the northeast at an approximate gradient of ' 0 007 ft/ft, and at the Knowles-Roek site ground water was inferred to be towards the east at an approximate gradient of 0 003 ft/ft Second zone (between 55 and 85 feet bsg) ground water flow direction at both sites was Inferred to be towards the east-northeast at a gradient of 0 004 ft/ft or less, ' and at the Knowles-Roek site ground water in the second zone was inferred to be towards the east to northeast at an approximate gradient of 0 004 ft/ft The ground water elevation data collected during the November 2003 ground water monitoring event is depicted in Figures 3 and 4 3 2 LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES ' A total of sixteenound water les were submitted to Cal Tech Environmental Laboratories, �' samples ' a DHS-certified laboratory, for analysis referenced in Section 2 3 TPH-g was detected in water samples collected from wells MW-3, MW-5, MW-6 (A - E), MW-7 ' (D -E),MW-8,VW-1C, VW-2A and VW-3A at concentrations as high as 140,000 micrograms per liter (µg/l) in the sample collected from VW-2A ' Benzene was detected in the above monitoring well samples at a maximum concentration of 23,000 µg/1 (VW-IC) Other BTEX compounds were detected in the above monitoring well samples at concentrations as high as 75,000 µg/1 (toluene from VW-1C) ' MTBE was detected in ground water samples collected from wells MW-3,MW-6(A-E),VW-1 C, VW-2A and VW-3A at concentrations as high as 5,400 µg/1 (MW-6B), 1,2-DCA was detected in ' ground water samples collected from wells VW-IC, VW-2A and VW-3A at concentrations as high as 380 µg/l (VW-2A) Advanced GeOEnvironmentai,In► 1