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04 March 2002 AGE-NC Project No 95-0130 Page 4 of 6 ' VW-2A at concentrations as high as 150 ,ug/l There were no reported detections of 1,2-DCA or EDB in any other ground water samples analyzed I 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 4275 and McCampbell Analytical Inc I D Nos ' 86149 through 86166) and chain-of-custody forms are presented in Appendix B 4.0. SUMMARY AND CONCLUSIONS The implications from the December 2001 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 decrease of ground water elevation of approximately 4 09 feet between the August 2001 and the December 2001 monitoring events is likely part of the seasonal ground water fluctuation, decreasing ground water elevations have been reported at 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 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, 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 and MW-7B located near the former UST pit ' No 2 (Figure 2) which is consistent with previous monitoring event results The greatest concentrations of dissolved MTBE was detected in the sample collected from well MW-6A (Figure 4) which is located near the former UST pit No 1 which suggests the possibly of ' two separate releases • Reported concentrations of MTBE have not demonstrated an increasing or decreasing trend ' during the ground water monitoring program • The only detection of dissolved TBA was in the sample collected from well VW-2A, ' however, TBA was previously detected at wells MW-1, MW-2, MW-3, MW-5, VW-1C, Advanced GeoEnvironmental,Inc