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01 October 2004 . AGE-NC Project No 95-0130 Page 5 of 6 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 28 feet below MSL(Table 2) • 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-1 C, 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 concentrations were detected as high as 130,000 µg/l from well VW-2A Additionally, the deepest detection of dissolved TPH-g and BTEX were detected in samples collected from well MW-6E, immediately southeast of the office building • Very high concentrations of TPH-g and BTEX were detected in the samples collected from well MW-6E during the 09 February 2004 sampling event Well MW-6 was re-sampled on 19 February 2004 to confirm the concentrations detected during the 09 February sampling event TPH-g and BTEX concentrations detected during the 19 February sampling were much Iower and consistent with concentrations detected in previous sampling events • The greatest concentrations of Top Filling Station dissolved MTBE were detected in the samples collected from wells VW-3A (screened 43 to 63 feet), MW-6B (screened 50 to 55 feet)and MW-6C(screened 70 to 75 feet)which are located immediately south and southeast Iof the office building (Figures 6 and 8) • Significant concentrations of 1,2-DCA were detected or have consistently been detected from wells MW-3, MW-8, MW-6B, MW-6C, VW-1B, 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 • EDB has previously been detected from wells MW-7B, VW-1B, VW-1C and VW-2A at concentrations significantly above the DHS's Maximum Contaminant Level (MCL) in drinking water • The high concentrations of petroleum hydrocarbons detected in samples collected from wells 1 MW-6(B and C),MW-7(A and B),VW-1 C,VW-2A and VW-3A indicated that these wells are within or near the dissolved petroleum hydrocarbon"core area"of the plume (Figures 5 through 8) • IAdvanced Geo Envi ron mental,Inc 1