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' 10 December 2002 • AGE-NC Project No. 98-0520 ' Page 3 of 4 a 3.2. ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in the water samples collected from wells MW-1,MW-2,MW-3,MW-5,MW-8 and MW-9 at concentrations ranging from 170 micrograms per liter (µg/1) in MW-9 to 1,600 µg11 in MW-5 (Figure 4). Toluene, ethylbenzene, and total xylenes were detected in well MW-5 and toluene was detected in ' well MW-3 at concentrations ranging from 3.0 µg/l toluene to 21 µg/l'xylenes in well MW-5. Benzene was not detected at or above laboratory reporting limits in any of the ground water samples. ' Fuel additives were'not detected at or above laboratory reporting limits in the ground water samples collected. ' Analytical results of ground water samples are summarized on Table 2.The laboratory report(CTEL . Lab I.D. No. 0209-110-1 through 0209-110-10) and chain-of-custody forms are included in Appendix B. ''• 4.0. SUMMARY AND CONCLUSIONS Based upon data collected from the site, AGE concludes: • Depth to ground water at the ' site' averaged approximately 2 3.6 1 feet bsg on 18.September 2002. ' On 18 September 2002 the ground water elevation at the site averaged approximately 12.95 feet above mean sea level, with a net flow towards the northwest under an average, gradient of 0.0006 ft/ft. ' TPH-g concentrations remained relatively stable in ground water "samples collected from MW-1, MW-2, MW-3 and MW-5 through MW-10 compared with the previous quarterly imonitoring event. TPH-g concentrations decreased to non-detect in the sample collected from well MW-4 . ' Various BTEX compounds except benzene were detected in two of the ten ground water monitoring wells. The concentrations of the BTEX compounds were below the DHS Maximum Contaminant Levels (MCLs) for drinking water. ' MTBE was not detected this quarter in samples collected from the wells MW-1 through MW-10. ' The vertical extent of impacted ground water has been defined.Impacted ground water does not extend beyond 45 feet bsg. ' Advanced GeoEnvi ron mental,Inc.