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' 01 October 2004 AGE-NC Project No. 98-0520 ' Page 3 of 4 3.2. ANALYTICAL RESULTS OF GROUND WATER SAMPLES PH-g was detected in the ground water samples collected from wells MW 1 through MW-3 and MW-5 at concentrations ranging from 120,micrograms per liter (µg11) (MW-1) to 1,300 µg/1 (MW-2). Figure 4 illustrates the approximate distribution of dissolved TPH-g. Ethylbenzene was detected in sample MW-5, at a concentration of 3.1 µg/l. 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. CT214-0406167), 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. t 4:0. SUMMARY ANDN L N CO C USIO 5 Based upon data collected from the site, AGE concludes: • On .17 June 2004 the ground water elevation at the site averaged approximately 11.77 feet ' above MSL,which represents an elevation decrease of approximately 2.23 feet since the last monitoring event. Net ground water flow was toward the northwest at an average gradient of 0.002 foot/foot. ' 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 decreased this quarter in wells MW-1 through MW-3 and MW-5. • Ethylbenzene was detected in MW-5; the concentration was below the.DHS Maximum Contaminant Levels (MCLs) for drinking water. ' & 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.