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03 July 2003 AGE-NC Project No 95-0130 Page 4 of 6 VW-2A at a concentration of 9 3 µg/l EDB was detected in a water sample collected from VW-1 C at a concentration of 45 gg/l 1,2-DCA was detected In ground water samples collected from wells MW-6C, MW-7 (A and B), VW-1B, VW-1C and VW-2A at concentrations as high as 260 µg/l (VW-2A) No other fuel components were detected in the groundwater 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 552 1)and chain-of-custody forms are presented in Appendix B 4.0. SUMMARY AND CONCLUSIONS IThe implications from the March 2003 ground water monitoring event are as follows • Ground water flow direction was inferred to be towards the northeast at a gradient of 0 007 ft/ft in the area bound by wells MW-1 through MW-5 The wells utilized for the ground water gradient and flow direction depicted in this report represent ground water from a depth of 50 to 80 feet bsg and therefore may not be truly representative of the upper most portion of water table • Between January 1995 and June 1999,ground water elevations at the site generally increased from 44 feet to 21 feet below MSL,however,between June 1999 and present, ground water elevations at the site have decreased from 21 feet to the current 27 feet below MSL(Table 2) ' • The increase of ground water elevation of approximately 0 79 feet between the December 2002 and the March 2003 monitoring events may be due to seasonal ground water fluctuation • Ground water at the site is above the screen intervals of wells MW-1 through MW-5,MW-6 (B-E), MW-7 (B-E), VW-1C, 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 and MW-7A 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 4) which is consistent with previous monitoring results,TPH-g concentrations were detected as high as ' 210,000 µg/1 from well VW-1B • 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 Significant increasing MTBE concentrations have been reported from well MW-6A during . the past Ebur consecutive ground water monitoring events Advanced GeoEnvironmental,Inc