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1 r - ' 17 December 2004 . AGE-NC Project No 95-0130 ' Page 4 of 6 ' samples collected from wells MW-2, MW-3, MW-6(B-D), MW-7(B, C), VW-1C, VW-2A and VW-3A at concentrations as high as 95 gg/l (VW-1C) ' No other fuel components were detected in the ground water samples Previous and current analytical results of ground water monitoring well samples are summarized in Tables 3 and 4 The laboratory reports (Cal Tech Environmental Project No CT214-0405069) and chain-of-custody forms are ' presented in Appendix C, GeoTracker confirmation pages of the submitted laboratory electronic deliverable format (EDF) files are Included in Appendix D ' 4.0. SUMMARY AND CONCLUSIONS ' The Implications from the May 2004 ground water monitoring event are as follows • Ground water flow direction within Hydrologic Units 1, 2 and 3 was Inferred to be towards the east-northeast at a gradient of 0 006 foot/foot or less (Figures 3 and 4) • Between January 1995 and August 2001, ground water elevations at the site generally '. Increased from 44 feet to 23 feet below MSL, since August 2001 and present day, ground water elevations have generally fluctuated between 24 feet and 28 feet below MSL(Table 2) ' • Ground water at the site was generally observed between 42 and 43 feet bsg and was above the screened Intervals of wells MW-1 through MW-5, MW-6(B-E), MW-7(B-E), VW-1 C, VW-2A and VW-3A (I a screened below ground water elevation), and may not yield samples fully representative of shallowest ground water conditions • The greatest concentrations of Top Filling Station dissolved TPH-g and BTEX were detected in samples collected from wells VW-2A and VW-1C (Figures 5 and 7, area Immediately north of the office building) which is consistent with previous monitoring results TPH-g concentrations were detected as high as 180,000 gg/1 from well VW-2A Additionally, the I deepest detection of dissolved TPH-g and BTEX were detected in samples collected from well MW-6E, immediately southeast of the office building • The greatest concentrations of Top Filling Station dissolved MTBE were detected in the samples collected from wells VW-3A (screened 43 to 63 feet), MW-6B (screened 50 to 55 feet)and MW-6C(screened 70 to 75 feet)which are located immediately south and southeast of the office building (Figures 6 and 8) • Significant concentrations of 1,2-DCA were detected or have consistently been detected from wells MW-3, MW-8, MW-6B, MW-6C, VW-1B, VW-1C, VW-2A, VW-2B and VW-3A Iindicating a significant 1,2-DCA-impact to ground water at the site ■ Advanced GeoEnvironmental,Inc I