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i28 December 2005 AGE-NC Project No 98-0511 Page 3 of 4 toward the southwest,off-site in the area of well MW-8,under a hydraulic gradient of approximately 0 008 foot/foot (ft/ft) or Iess 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in the ground water sample collected from monitoring well MW-1 at a concentrations of 7,100 micrograms per liter (µg/1) BTEX was detected in well MW-1 at concentrations of 59 µg/1 benzene, 81 pg/l toluene, 980 �tg/l ethylbenzene, and 6,100 µg11 xylenes Maps showing the approximate distributions of dissolved TPH-g and benzene at the site are illustrated on Figures 4 and 5, respectively I MTBE was detected in the ground water samples collected from well MW-5 at a concentration of 16 µg11 ' No other constituents of concern were detected at or above laboratory reporting limits Analytical results of ground water samples are summarized in Table 2 Copies of the laboratory report (CTEL Project No CT214-0506215), quality assurance/quality control report, and chain of custody forms are provided in Appendix D Documents confirming the upload of laboratory electronic deliverable format (EDF) files and depth to water measurements to GeoTracker are provided in Appendix E 4.0. SUMMARY AND CONCLUSIONS Based upon data collected from the site during the June 2005 investigation, AGE concludes the following • Ground water elevations in the monitored area averaged 3 34 feet above MSL, indicating a decrease in ground water elevation of approximately 0 77 feet since the previous quarter Ground water at the site was inferred to flow generally toward the northwest under hydraulic gradients ranging from approximately 0 004 ft/ft to 0 015 ft/ft I • TPH-g was detected in the ground water sample collected from monitoring well MW-1 at a concentration of 7,100µg/l BTEX was detected in well MW-1 at concentrations of 59µg/l benzene, 81 µg/1 toluene, 980 µg11 ethylbenzene, and 6,100 µg/l xylenes The detected concentrations of benzene and xylenes were above the DHS' maximum contaminant levels (MCL) for these contaminants in drinking water • MTBE was detected in the ground water samples collected from well MW-5 at a concentration of 16 µg/1, these concentrations are above the MCL (13 µg/1) for MTBE in • drinking water However, the MTBE concentrations in well MW-5 have been consistently Advanced GeoEnvironmentai,Inc I