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' 28 June 2002 i AGE-NC Project No 95-0130 ' Page 4 of 6 detected In a ground water sample collected from well VW-1C at a concentration of 77 µg/l There ' were no reported detections of 1,2-DCA or EDB in any other ground water samples analyzed 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 (Castle Analytical Laboratory Reference No 4475 and McCampbell Analytical Inc I D No 0203139) and chain-of-custody forms are presented in Appendix B I4.0. SUMMARY AND CONCLUSIONS The implications from the March 2002 ground water monitoring event are as follows • Ground water flow direction was inferred to be towards the northeast at a gradient of 0 004 ft/ft in the area bound by wells MW-1 through VW-3 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 • The Increase of ground water elevation of approximately 1 97 feet between the December 2001 and the March 2002 monitoring events is likely part of the seasonal ground water fluctuation,prior to March 2002,decreasing ground water elevations had been reported Iat the site since the May 2001 ground water monitoring event • Ground water at the site is above the screen Intervals of wells MW-1, MW-2, MW-3,MW-4, MW-5, MW-6 (B, C, D and E), MW-7 (B, C, D and E) and VW-1C (I e screened below ground water elevation), and may not yield samples fully representative of shallowest ground water conditions The ground water table was within the screen interval of wells MW-6A, MW-7A, VW-1B, VW-2A and VW-3A 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, MW-6A and MW-7B (Figure 2) which is consistent with previous monitoring results The greatest concentrations of dissolved MTBE I was detected in the sample collected from well MW-6A (Figure 4) which is located Immediately east of the former UST pit No 1 • Reported concentrations of MTBE have not demonstrated an increasing or decreasing trend during the ground water monitoring program • Significant concentrations of 1,2-DCA were detected or have consistently been detected from I wells MW-2, MW-3, MW-6B, MW-6C, MW-7A, MW-7B, VW-1B, VW-1C, 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 samples collected from wells MW-5, IAdvanced GeoEnvi ron mental,Inc I