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' 30 April 2000 AGE-NC Project No 97-0333 ' Page 3 of 5 ' feet below the tops of well casings,ground water elevations were calculated to be between 16 64 feet and 16 69 feet above mean sea level Ground water elevation at the site increased an average 1 09 feet between the October 2000 and the January 2001 ground water monitoring events The ground ' water elevation data for MW-1 through MW-5 during the January 2001 ground water monitoring event is depicted in Figure 3 Ground water flow direction for the area bound by wells MW-1 through MW-5 was inferred to be towards the north at a gradient of 0 001 ft/ft or less, or ' approximately 5 feet per mile (Figure 3) ' 3 2 LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES A total of five ground water samples were submitted to a DHS-certified laboratory in January 2001 ' TPH-g was detected in water samples collected from wells MW-1, MW-2, MW-3 and MW-4 at concentrations as high as 120,000 micrograms per liter (µg/1), however the laboratory reported the sample chromatograms from MW-1 and MW-4 as having isolated peaks and samples MW-2, MW-3 ' and MW-4 as having significant unmodified or weakly modified gasoline TPH-d was detected in water samples collected from MW-2, MW-3 and MW-4 at concentrations as high as 2,700 µg/1, ' however, the laboratory reported the TPH-d sample chromatograms to contain significant gasoline range compounds ' BTEX compounds were detected in the ground water samples collected from wells MW-2, MW-3, MW-4 and MW-5 at concentrations as high as 23,000 4gll (MW-2, toluene) The highest benzene concentration was detected in the water sample collected from well MW-2 at a concentration of ' 9,900µg/1 MTBE was detected at concentrations as high as 950,000µg/] in water samples collected from MW-1, MW-2 and MW-3 by the EPA 8020 analysis MTBE was detected in water samples collected from MW-1, MW-2 and MW-3 utilizing EPA Method 8260 Modified at concentrations as high as 730,000µg/I TAME was detected in a water sample collected from MW-1 at a concentration of 200µg/1 No other fuel oxygenated compounds ' were detected above the respected laboratory reporting limits,however tetrachloroethene (PCE)was detected in a water sample collected from MW-4 at a concentration of 4,900µg/1, trichloroethene (TCE) from MW-5 at a concentration of 1 2 µg/l, 1,2,3-trichlorobenzene from MW-2 at a ' concentration of 51,000µg/l and hexachlorobutadiene from MW-1 and MW-2 at concentrations of J 190 and 30,000 mg/l,respectively Previous and current analytical results of ground water monitoring f well samples are summarized in Tables 2 and 3 The laboratory reports(McCampbell Analytical Inc E ' I D No 59229 through 59233) and chain-of-custody forms are presented in Appendix B 1 ' Advanced GeoEnvironniental Inc