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' 21 December 2001 AGE-NC Project No 96-0254 ' Page 3 of 4 ' The depths to ground water in wells MW-1 through MW-7 and GLMW-3 were measured between 6 98 feet and 9 14 feet below the tops of the well casings Ground water elevations at the site ranged from 28 57 feet above mean sea level (MSL) in well GLMW-3 to 30 26 feet above MSL In well ' MW-6 Ground water elevations in wells MW-1, MW-2, MW-3, MW5 and MW-6 at the site decreased an average 0 06 feet between the July 2001 and October 2001 sampling events Ground water elevations in wells MW-4 and MW-7 at the site decreased 0 86 feet and 1 71 feet respectively ' between the July 2001 and October 2001 sampling events The ground water flow direction for the 24 October 2001 sampling event was inferred to be toward the north at an average hydraulic gradient of 0 005 feet/feet Data from MW-1A, MW-2A, MW-4 and MW-7 was not used to determine ground water gradient Wells MW-lA, MW-2A and MW-7 are screened at a deeper Interval than the other wells and the ground water elevation in MW-4 was much lower than the surrounding wells Figure 3 illustrates the contoured ground water elevations 32 LABORATORY RESULTS OF GROUND WATER SAMPLES . TPH-g was detected in the samples collected from wells MW-1B, MW-4 and MW-7 at concentrations of 410 micrograms per liter(µg/1), 650 µg/1 and 90 µg/1 TPH-d was detected in the water samples collected from wells MW-4 and MW-7 at concentrations of 110 µg/l and 91 µg/1 ' TPH-g and TPH-d were not detected in the remaining samples BTEX compounds were detected in the ground water samples collected from monitoring wells MW-1 B,MW-4 and MW-7 at concentrations as high as 140 µg/1 benzene, 26 µg/1 toluene,45 µg/1 ethylbenzene and 3 7 µg/1 xylenes MTBE was detected by EPA Method 8260 in the samples collected from MW-lB and MW-4 at concentrations of 19 µg/1 and 3 6 µg/1 No other fuel oxygenates were detected in the ground water samples The analytical results are summarized in Table 2 Copies of the laboratory reports(MAI Laboratory ID 82054 to 82062), QA/QC reports and chain-of-custody forms are in Appendix B I 4.0. SUMMARY AND CONCLUSIONS ' Based on the data collected during this monitoring period, AGE concludes • The depth to ground water at the site was between 6 98 to 9 14 feet below the well casing tops Ground water elevations in wells MW-1, MW-2,MW-3,MW5 and MW-6 at the site I decreased an average 0 06 feet between the July 2001 and October 2001 sampling events Advanced GeoEnvironmental Inc