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i ' 30 August 2001 . AGE-NC Project No 95-0130 Page 4 of 5 ' water samples analyzed No other fuel components were detected in any other ground water samples Previous and current analytical results of ground water monitoring well samples are summarized in Tables 2 and 3 The laboratory reports (Castle Analytical Laboratory I D No 68781 through 68791) and chain-of- custody forms are presented in Appendix B 4.0. SUMMARY AND CONCLUSIONS IThe implications from the May 2001 ground water monitoring event are as follows I • 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, MW-3 and MW-5, ground water flow was inferred towards the east at a gradient of 0 005 ft/ft In the area bound by wells MW-1, MW-2, MW-3 Iand MW-4 • Ground water at the site Is approximately 15 to 25 feet above (drowned) the screen intervals at wells MW-1, MW-2, MW-3, MW-4 and MW-5 (I a screened below ground water I elevation), and may not yield samples fully representative of shallowest ground water conditions, wells VW-1C, V W-2A and VW-3A are approximately five to ten feet ' "drowned" The ground water elevation appeared to be withing the screen intervals of wells VW-1B, VW-2B and VW-3B and should be representative of shallowest ground water conditions ' • The Increase of ground water elevation of approximately 0 67 feet between the February 2001 and the May 2001 monitoring events Is likely part of the seasonal ground ' water fluctuation • The only detection of dissolved TBA was In the sample collected from off-site crossgradient well MW-5 at a concentration of 35 ,ug/l ' • The reported concentrations of MTBE have decreased compared to ground water samples analyzed during the February 2001 monitoring event However, reported concentrations of I MTBE have not demonstrated an Increasing or decreasing trend during the ground water monitoring program • The elevated concentrations of petroleum hydrocarbons detected in samples collected from wells VW-1, VW-2 and VW-3 Indicate that these wells are within or near the dissolved petroleum hydrocarbon "core area" of the plume (Figures 4 and 5) • The lateral extent of the dissolved petroleum hydrocarbon plume is not known toward the . west, northwest,north,northeast and east of the area bound by wells MW-1 through VW-3, IAdvanced GeoEnvironmental,Inc I