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i 27 February 2004 AGE-NC Project No 95-0130 Page 4of6 No other fuel components were detected in the ground water samples Previous and current analytical Iresults of ground water monitoring well samples are summarized in Tables 3 and 4 The laboratory reports (Cal Tech Environmental Laboratories I D No 0311-068) and chain-of-custody forms are presented in Appendix C I4.0 SUMMARY AND CONCLUSIONS The Implications from the November 2003 ground water monitoring event are as follows ' - Ground water at depths between 35 and 80 feet bsg (Hydrologic units 1, 2 and 3) was Inferred to be towards the east-northeast at a gradient of 0 007 feet/feet or less(Figures 3 and 4) ' - Between January 1995 and August 2001, ground water elevations at the site generally Increased from 44 feet to 23 feet below MSL, since August 2001 and present day, ground ' water elevations have generally fluctuated between 24 feet and 27 feet below MSL(Table 2) • The decrease of ground water elevation of approximately 0 77 feet between the August 2003 ' • and the November 2003 monitoring events may be due to seasonal ground water fluctuation Ground water at the site was generally observed between 43 and 44 feet bsg and was above the screened intervals of wells MW-1 through MW-5,MW-6(B-E),MW-7(B-E), VW-1C, ' VW-2A and VW-3A (I e screened below ground water elevation), and may not yield samples fully representative of shallowest ground water conditions ' - The greatest concentrations of Top Filling Station dissolved TPH-g and BTEX were detected in samples collected from wells VW-2A and VW-1C (Figures 5 and 7, area immediately north of the office building) which Is consistent with previous monitoring results TPH-g 1 concentrations were detected as high as 140,000 µg/l from well VW-2A Additionally, the deepest detection of dissolved TPH-g and BTEX were detected in samples collected from well MW-713, immediately north of the office building r - The greatest concentrations of Top Filling Station dissolved MTBE were detected In the samples collected from wells VW-3A(screened 43 to 63 feet) and MW-6B (screened 50 to ' 55 feet) which are located Immediately south and southeast of the office building (Figures 6 and 8) Significant concentrations of 1,2-DCAwere detected orhave consistently been detected from ' wells MW-2, MW-3, MW-6B, MW-6C, MW-7A, MW-7B, VW-IB, VW-1C, VW-2A, VW-2B and VW-3A indicating a significant 1,2-DCA-Impact to ground water at the site ' - TBA was not detected In any of the analyzed water samples,however, TBA was previously detected In wells MW-1, MW-2, MW-3, MW-5, VW-1C, VW-2A, VW-2B and VW-3A, suggesting a minor TBA-Impact to ground water at the site Advanced GeoEnvironmental,Inc 1