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' 05 June 2003 AGE-NC Project No. 98-0520 . ' Page 3 of 4 ' 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 and MW-5, at concentrations ranging from 1,200 micrograms per liter(µg/1) in MW-1 to 2,500 µg/l in MW-5. Figure 4'illustrates the approximate distribution of dissolved TPH-g. ' Ethylbenzene was detected in samples MW-2,MW-3 and MW-5 at a maximum concentration of 300 �tg/l, and xylenes were detected in well MW-5 at a concentration of 293 µg/1. Benzene and toluene were not detected at or above laboratory reporting limits in any of the ground water samples. No other analytes were 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 Project. No. CT214-0303128) and chain-of-custody forms are included in Appendix D. 4.0. SUMMARY AND CONCLUSIONS Based upon data collected from the site, AGE concludes: ' On 18 March 2003 the ground water elevation at the site averaged approximately 16.04 feet above MSL showing an elevation increase of approximately 0.26 feet since the last monitoring event. Ground water flow was.northwest at an average gradient of 0.001 feet/feet ' which is slightly lower than last quarter. The ground water flow direction has been consistently northwest since the initiation of ground water monitoring in December 1999. ' TPH-g concentrations showed a marked increased in ground water samples collected from MW-1 through MW-10,however levels are still well below historical highs.TPH-g was not detected in samples MW-4 and MW-9 for the second consecutive monitoring event; and ' TPH-g was not detected in MW-8 for the first time. TPH-g has not been detected in deep- screened well MW-6 since the well was installed in December 2001. • Ethylbenzene,and total xylenes were detected in MW-5 and only ethylbenzene was detected in MW-2 and MW-3. All the concentrations were below the DHS Maximum Contaminant Levels (MCLs) for drinking water. ' The vertical extent of impacted ground water has been defined.Impacted ground water does not extend beyond 45 feet bsg. ' The lateral extent ofpetroleum hydrocarbon-impacted ground water has not been adequately defined northwest of the former USTs. Advanced GeoEnviron mental,Inc.