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I30 September 2003 • AGE-NC Project No 95-0130 IPage 4 of 6 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 the water table ' • Between January 1995 and June 1999,ground water elevations at the site generally Increased from 44 feet to 21 feet below MSL, fluctuated between 21 feet and 23 feet below MSL between June 1999 and August 2001,and fluctuated between 24 feet and 27 feet below MSL Ibetween December 2001 and June 2003 (Table 2) • The Increase of ground water elevation of approximately 0 44 feet between the March 2003 ' and the June 2003 monitoring events may be due to seasonal ground water fluctuation • Ground water at the site was generally observed at 42 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 a screened below ground water elevation), and may not yield samples fully representative of shallowest ground water conditions • The greatest concentrations of dissolved TPH-g and BTE&X were detected in samples collected from wells VW-1 C,VW-2A and MW-7B(Figure 4,area Immediately north of the office building)which is consistent with previous monitoring results TPH-g concentrations • were detected as high as 180,000 µg/1 from well V W-1 C • The greatest concentration of dissolved MTBE was detected in the sample collected from Iwell VW-3A(Figure 5) which is located Immediately south of the office building • Significant concentrations of 1,2-DCA were detected or have consistently been detected from wells MW-2, MW-3, MW-6B, MW-6C, MW-7A, MW-7B, VW-1B, VW-1C, VW-2A, IVW-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 significant TBA-Impact to ground water at the site I • EDB has previously been detected in wells MW-7B, VW-lB, VW-1C and VW-2A in concentrations significantly above the DHS's Maximum Contaminant Level (MCL) in drinking water ' • The high concentrations ofpetroleum hydrocarbons detected in samples collected from wells MW-6 (A and B), MW-7 (A and B), VW-1 (B and C), VW-2A and VW-3A indicated that these wells are within or near the dissolved petroleum hydrocarbon"core area"of the plume I (Figures 4 and 5) • The lateral and vertical extent of the dissolved petroleum hydrocarbon plume is not known Itoward the northwest, north,northeast,east and southeast of the area bound by wells MW-1 • through MW-5 (Figures 4 and 5) Advanced GeoEnvironmental,Inc