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21 February 2005 . AGE-NC Project No 99-0624 Page 3 of 4 to 56 76 feet below the tops of the well casings(toc) Ground water elevations at the site ranged from ' 17 33 feet below mean sea level (MSL) in well MW-4 to 17 86 feet below MSL in well MW-2 (Table 1) During this monitoring event,the ground water levels in wells MW-1 through MW-6 were at least ten feet below the tops of the well screens, indicating that the wells are screened properly to yield representative shallow ground water samples The ground water elevation at the site Increased approximately 146 feet between the August 2004 and November 2004 monitoring events The ground water was Inferred to be flowing radially Inward towards a southeast-trending ground water trough in the area of MW-2,ground water gradients ranged between 0 006 and 0 008 foot per foot(ft/ft) Figure 3 Illustrates the contoured ground water elevations as measured on 08 November 2004 ' 32 ANALYTICAL RESULTS OF GROUND WATER SAMPLES ' TPH-g was detected in ground water samples collected from wells MW-1 through MW-3, MW-5 and MW-7 at concentrations of between 130 µg/l (MW-5) and 43,000 µg/l (MW-2) Benzene was only detected in the samples collected from well MW-2 at a concentration of 10 µg/l The fuel Additive MTBE was detected in samples from wells MW-1 through MW-3, MW-5 and MW-7 at concentrations of between 130 µg/l (MW-5) and 43,000 µg/l (MW-2) ' No other constituents of concern were detected above laboratory reporting limits in the analyzed samples Previous and current analytical results of ground water monitoring well samples are summarized in Table 2 The laboratory report (CTEL Project No CT214-0411064) and chain of ' custody forms are presented in Appendix D Confirmation pages of the submitted laboratory electronic digital format(EDF) files and depth to water measurements are included in Appendix E I 4.0. SUMMARY AND CONCLUSIONS ' The following conclusions were drawn from the results of this Investigation ' The depth to ground water at the site was between 55 61 feet and 56 76 feet toc, the calculated ground water elevation was ranged between 17 33 feet and 17 86 feet below MSL • Ground water flow direction in the area of wells MW-1 through MW-6 was inferred to be ' flowing radially inward towards a southeast-trending ground water trough in the area of MW-2 at gradients of between 0 006 and 0 008 ft/ft Due to the low hydraulic gradient at the ' site, slight variations in ground water measurements or changes of recharge/discharge of the local ground water could greatly modify the inferred ground water flow direction ' Advanced GeoEnvironmental,Inc