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' 24 March 2004 AGE-NC Project No 97-0301 1 Page 3 of 5 ' 3.0. FINDINGS Ground water elevation, flow direction and gradient were determined from field data collected on 19 September 2003 The contaminant Impact to ground water was quantified by the ground water laboratory data 3 1 GROUND WATER ELEVATION AND GRADIENT ' The depths to ground water in wells MW-1 through MW-12 were measured at between 3 47 and 35 36 feet below the tops of well casings The ground water elevations in the wells scre across the water table were calculated to be between 2139 feet (MW-SA) and 22 57 feet (MW- 1D) below ' mean sea level The First Water Zone ground water elevation data obtained during this monitoring event are depicted in Figure 3 The Inferred ground water flow direction for the area was Inferred to be east-northeast at a gradient of 0 003 ft/ft or less(Figure 3) Generally, ground water elevation at ' the site decreased an average 2 20 feet between the June 2003 and the September 2003 ground water monitoring events (on IJ u NW5 mAl 1,24�� lei 7 X, C eel o lie 3 2 LABORATORY RESULTS OF GROUND WATER SAMPLES ' A total of twenty-six groundwater samples were submitted to Cal Tech Environmental Laboratories, a DHS-certified laboratory, for analysis ' TPH-g was detected in two water samples collected from wells MW-1 and MW-7 at concentrations of 6,100 micrograms per liter(pg/1)and 4,900 gg/l,respectively The estimated extent of dissolved TPH-g in First Water Zone is depicted in Figure 4 For the first time, TPH-d, TPH-k and TPH-mo were not detected in any of the twenty-six water samples Various BTEX constituents were detected in water samples collected from wells MW-land MW-7 at concentrations as high as 3,000 µg/1 ' benzene in the sample collected from MW-7 MTBE was detected in one water sample collected from well MW-1 at a concentration of 15 µg11 ' (MW-8A) 1,2-DCA was detected in 2 groundwater samples collected from wells MW-1 and MW-7 at concentrations of 46 µg11 and 450 µg11, respectively 4 c, k e f o A kS 0 i Q*rn w 7� ' No other fuel components were detected in the ground water sample Previous and current analytical y�'J.64 results of ground water monitoring well samples are summarized in Tables 3 and 4 The laboratory f -+ reports (Cal Tech Environmental Laboratories 1 D No 0309-126) and cham-of-custody forms are ' presented in Appendix B i Advanced GeoEnvironmental,Inc I I