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17 February 2006 • AGE-NC Project No 98-0511 tPage 3 of 4 ' 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in the ground water sample collected from monitoring well MW-I at a t concentration of 28,000 micrograms per liter(µg/l) BTEX compounds were detected in well MW-1 at concentrations of 71 µg/l benzene, 75 µg/1 toluene, 1,600 µg/1 ethylbenzene, and 6,600 µg/l xylenes Maps showing the approximate distributions of dissolved TPH-g and benzene at the site are ' Illustrated on Figures 4 and 5, respectively MTBE was detected in the ground water sample collected from well MW-5 at a concentration of ' 23 µg/l 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 CT214-0511052), quality assurance/quality control (QA/QC) report, and chain of custody forms are provided in Appendix C Documents confirming the upload of laboratory ' electronic deliverable format (EDF) files and depth to water measurements to GeoTracker are provided in Appendix D ' • 4.0. SUMMARY AND CONCLUSIONS ' Based upon data collected from the site during the November 2005 Investigation, AGE concludes the following ' • Depths to ground water ranged from 16 33 feet to 16 98 feet below the tops of the well casings Ground water elevations at the site ranged from 1 16 feet above MSL to 1 55 feet above MSL, and averaged 141 feet above MSL, Indicating an Increase in ground water elevation of approximately 0 65 feet since the last monitoring event In September 2005 • Ground water at the site was inferred to flow toward the southwest on the southern portion ' of the site and radially Inward toward a depression In the potentiometric surface near well MW-1 on the northern portion of the site, calculated gradients ranged between 0 004 (ft/ft and 0 0009 ft/ft Ground water flow direction near the former UST area is consistent with flow directions observed during previous monitoring events • TPH-g was detected in the ground water sample collected from monitoring well MW-1 at a concentration of 28,000µg/l BTEX compounds were detected in well MW-1 at concentrations of 71 µg/1 benzene, 75 µg/1 toluene, 1,600 µg11 ethylbenzene, and 6,600 µg11 xylenes The detected concentrations of benzene and ethylbenzene in well MW-1 were above the DHS's maximum contaminant levels(MCLs) for these contaminants In drinking water • MTBE was detected in the ground water sample collected from well MW-5 at a Advanced GeoEnvironmental,Inc