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' 10 December 2004 AGE-NC Project No. 98-0520 tPage 3 of 4 3.2. ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in the ground water samples collected from wells MW-2, MW-3, and MW-5 at concentrations ranging from 540 micrograms per liter (µg/1) (MW-3) to 690 µg/l (MW-2). ' Figure 4.illustrates the approximate distribution of dissolved TPH-g. Ethylbenzene and xylenes were detected in sample MW-5 at concentrations of 15 �Lg/l and 4.9 µg11, respectively. 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 in Table 2. The laboratory report(CTEL Project No. CT214-0409074), quality assurance/quality control(QA/QC)report, and ' chain of custody forms are included in Appendix C.Documents confirming the upload of laboratory electronic deliverable format (EDF) files and depth to water measurements to GeoTracker are included in Appendix D. 4.0. SUMMARY AND CONCLUSIONS Based upon data collected from the site, AGE concludes: ' On 10 September 2004, the ground water elevation at the site averaged approximately 10.21 feet above MSL, which represents an elevation decrease of approximately 1.56 feet ' since the last monitoring event, and the lowest water level since initiation of monitoring in December 1999.Net ground water flow was toward the northwest under a gradient of 0.004 ft/ft or less. ' The ground water flow direction has been consistently northwest since the initiation of ground water monitoring in December 1999; however, the ground water gradient is very ' . shallow and seasonal changes can greatly influence the direction and pattern of ground water ' flow. • TPH-g concentrations significantly decreased this quarter in wells MW-1through MW-3 and ' MW-5, compared to the previous quarter. The decrease in petroleum hydrocarbon ; concentrations may be attributed to the lower water levels. ' Ethylbenzene and xylenes were detected only in well MW-5. Since December 2003, BTEX compounds have been detected only in well MW-5. • .The vertical extent of impacted ground water has been defined;TPH-g has not been detected ' in deep-screened well MW-6 since the well was installed in December 2001. Impacted ground water apparently does not extend beyond 45 feet below,surface grade (bsg). ' Advanced GeoEnvironmental,Inc.