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i 13 December 2002 AGE-NC Project No 95-0130 IPage 4 of 6 reports(Castle Analytical Laboratory Reference No 5034)and chain-of-custody forms are presented IIn Appendix C I4.0. SUMMARY AND CONCLUSIONS I The Implications from the September 2002 ground water monitoring event are as follows • Ground water flow direction was Inferred to be towards the northeast at a gradient of 0 006 ft/ft In the area bound by wells MW-1 through MW-5 Due to the low 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 I • The decrease of ground water elevation of approximately 129 feet between the June 2002 and the September 2002 monitoring events may be due to seasonal ground water fluctuation or a longer-term drought cycle, decreasing ground water elevations have generally been reported at the site since the May 2001 monitoring event • Ground water at the site is above the screen intervals of wells MW-1 through MW-5,MW-6 � . (B, C,D and E),MW-7 (B,C, D and 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 ground water table appeared to be within the screen interval of wells MW-6A, MW-7A and VW-1B and should be representative of shallowest ground water conditions • The greatest concentrations of dissolved TPH-g and BTEX were detected in samples collected from wells VW-1 (B and C), VW-2A and MW-7B (Figure 4) which is consistent with previous monitoring results I • The greatest concentrations of dissolved MTBE was detected in the sample collected from well MW-6A (Figure 5) which is located immediately east of the former UST pit No 1 Reported concentrations of MTBE have not demonstrated an increasing or decreasing trend rduring the ground water monitoring program 1 • Significant concentrations of 1,2-DCA were detected orhave consistently been detected from I wells MW-2, MW-3, MW-6B, MW-6C, MW-7A, MW-7B, VW-1B, VW-IC, VW-2A, VW-2B and VW-3A suggesting a significant 1,2-DCA-Impact to ground water at the site • The only detection of dissolved TBA was in the sample collected from wells MW-2 and MW-5, however, TBA was previously detected at wells MW-1, MW-3, VW-1C, VW-2A, VW-2B and VW-3A suggesting a significant TBA-impact to ground water at the site • EDB was not detected in any of the September 2002 samples, however, EDB has been detected at wells MW-7B, VW-2A and VW-2B in concentrations significantly above the DHS's Maximum Contaminant Level (MCL) in drinking water Advanced GeoEnvironmental,Inc I