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<br /> 04 March 2002
<br /> AGE-NC Project No 95-0130
<br /> Page 3 of 6
<br /> 3.0. FINDINGS
<br /> Ground water elevation, flow direction and gradient were determined from field data collected on
<br /> 10 December 2001, the contaminant Impact to ground water was quantified by laboratory analysis
<br /> of water samples collected on 11 December 2001
<br /> 3 1 RELATIVE GROUND WATER ELEVATION AND GRADIENT
<br /> The depths to ground water from the purged wells were measured between 41 48 and 42 73 feet
<br /> below the tops of well casings, ground water elevations were calculated to be between 25 11 feet and
<br /> 26 37 feet below mean sea level Ground water elevation at the site decreased an average 4 09 feet
<br /> between the August 2001 and the December 2001 ground water monitoring events Ground water
<br /> flow direction In the area bound by wells MW-1, MW-2, MW-3, MW-4 and MW-5 was Inferred to
<br /> be toward the northeast at a gradient of 0 004 ft/ft or less The ground water elevation data during
<br /> the December 2001 ground water monitoring event Is depicted In Figure 3
<br /> 3 2 LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES
<br /> A total of eleven ground water samples were submitted to a DHS-certified laboratory for analysis
<br /> TPH-g was detected In water samples collected from wells MW-2, MW-3, MW-5, MW-6 (A, B, C
<br /> and D), MW-7 (B, C and D), VW-1 (B and C), VW-2A and VW-3A at concentrations as high as
<br /> 270,000 micrograms per liter (ug/l), the most Intense TPH-g-Impact was detected at wells VW-1B
<br /> and VW-1C
<br /> BTEX compounds were detected In water samples collected from wells MW-2, MW-3, MW-5,
<br /> MW-6 (A, B, C, D and E), MW-7 (B, C, D and E), VW-1 (B and C), VW-2A and VW-3A at
<br /> concentrations as high as 77,000(ug/1)(toluene,VW-1B) The greatest benzene-Impact was detected
<br /> In ground water sample collected from well VW-IC at a concentration of 44,000 4g/1
<br /> I MTBE was detected (EPA Method 8260) In ground water samples collected from wells MW-2,
<br /> MW-3, MW-6 (A, B, C and D), MW-7B, VW-IB, VW-1C, VW-2A and VW-3A at concentrations
<br /> as high as 21,000,ug/1 (VW-3A) TBA was detected In a ground water sample collected from well
<br /> VW-2A at a concentration of 83 µg/l There were no reported detections of fuel oxygenating
<br /> compounds In any other ground water samples analyzed
<br />' 1,2-DCA was detected In ground water samples collected from wells MW-2, MW-3, MW-6B,
<br /> • MW-7B, VW-IB, VW-IC , VW-2A and VW-3A at concentrations as high as 170 ,ug/l (VW-2A)
<br /> EDB was detected In ground water samples collected from wells MW-7B, VW-1 B, VW-I C and
<br /> Advanced GeoEnviron mental,Inc
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