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08 November 1999 AGE-NC Project No 98-0448 Page 2 of 4 feet below the tops of the well casings Ground water elevations at the site were calculated to be between 8 98 feet and 10 48 feet below mean sea level, ground water elevations are depicted In Figure 3 Ground water elevation at the site decreased an average 0 88 feet between the June 1999 ; ' and the September 1999 ground water monitoring events, a general trend of decreasing ground water elevations has been observed at the site at least since March 1999 _ Ground water monitoring data collected in the area of wells MW-1, MW-2,MW4A, MW-6, MW-7 and MW-8 indicated a ground water flow direction generally toward the southeast at a gradient of " I 0 015 ft/ft, or approximately 80 feet per mile (Figure 3), ground water monitoring data collected in the area of wells MW-3,MW-5 and MW-8 suggested a ground water flow direction generally toward the west-northwest at a gradient of 0 004 ft/ft, or approximately 22 feet per mile Ground water was approximately 25 feet above the screened interval in monitoring well MW-413 Therefore this well is "drowned", and yields a sample representative of deeper screened ground water Due to the low gradient at the site, slight variations in ground water measurements or changes of recharge/discharge of the local ground water could greatly modify ground water flow direction 10 32 LABORATORY RESULTS OF GROUND WATER SAMPLES TPH-g was detected in water samples collected from wells MW-1, MW-2, MW-4A, MW-413 and MW-6 at concentrations ranging from 93 micrograms per liter (,Ug/1) to 90,000 µg/1 IVarious BTEX compounds were detected in water samples collected from MVL7-1, MW-2, MW-4A and MW-413 at concentrations ranging from 37 ug/1 and 16,000 ug/l, the greatest benzene concentrations were detected in samples collected from MW-413 at a concentration of 7,300 µg/l MTBE was detected utiIizmg EPA Method 8260 Modified in water samples collected from wells MWA, MW-413 and MW-8 at concentrations of 1 5 /.cg/l, 110 pg/1 and 3 4 µg/1, respectively DIPE was detected In water samples collected from wells MW-1 and MW-8 at concentrations of 6 Azg/l- and 4 7,ug/l,respectively No other fuel oxygenated compounds were detected during the Iaboratory analysis Analytical results of the ground water samples are summarized in Table 2 The laboratory reports (McCampbell Analytical Inc I D 19160 through 19168) and chain-of-custody forms are presented in Appendix B Advanced GeoEnaironmental,Inc f 1 `