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30 April 2005 AGE-NC Project No 96-0232 Page 6 of 9 The results from the ground water monitoring and sampling events performed in March 2005 are as follows • Generally, depth to ground water at the site varied between 8 and 12 feet bsg, ground water elevations ranged between 0 82 feet(MW-20B)and 3 24 feet(MW-5)below mean sea level (Table 2) • Net ground water flow direction In all informal hydrogeologic units was Inferred to be southeast at the Flag City Chevron site and inferred to be east-northeast at the Three B's Truck Plaza site,hydraulic gradients were calculated to be approximately 0 001 ft/ft or less Due to the low ground water gradient at the site, small variations In ground water measurements or changes of recharge/discharge of the local ground water could greatly modify the Inferred ground water flow direction (Figures 4 through 7) • The most Intense on-site Flag City Chevron MTBE concentrations were detected from Second Zone well MW-8A at 400 µg/l (Figure 9), concentrations of on-site MTBE were detected from First Zone wells MW-2 (130 µg/1 ) and MW-4 (0 67 µg11 ), a significant MTBE Increase was reported at well MW-2 (Figures 8 and 9) • The most intense off-site MTBE concentrations were detected north of the site from First Zone wells MW-19 A and MW-20A at concentrations as high as 440 µg/l, low to moderate MTBE concentrations were detected in First Zone wells west of the site at Three B's Truck Plaza from wells MW-1,MW-2, MW-4,MW-5, MW-l0A and at Rocky's Restaurant from wells MW-7 and MW-16 (Figure 8) Between the June 2004 and March 2005 quarterly monitoring events,a significant MTBE decrease was reported at well MW-19A, from 4800 µg/l to 1,300 µg/1 to 900 µg11 to 240 µg/1 (Figure 8, Table 3) • Low to moderate off-site MTBE concentrations(as high as 97µg/1)were detected in Second Zone wells west-southwest of the site at Rocky's Restaurant from wells MW-11 A,MW-14, MW-17, west-northwest of the site from at Three B's Truck Plaza from wells MW-8B, MW-9A,MW-10,MW-11 B,and north of the site at McDonaId's Restaurant from well MW- 20B (Figure 9) • Low to moderate offsite MTBE concentrations (as high as 140 µg/l) were detected in Rocky's Upper Zone wells west of the site at Rocky Restaurant from wells MW-11B, MW-15 and MW-18 (Figure 10, Table 4) • Low concentrations of TPH-d have been detected at various wells during previous quarterly monitoring events at Flag City Chevron During December 2004, a low concentration of TPH-d was detected in the water samples collected from well MW-12A AGE had previously asked McCampbell Analytical Laboratory to review the TPH-d sample chromatograms from MW-12A, the laboratory concluded that the low TPH-d detections from MW-12A did not have typical diesel characteristics,and that the detected chromatogram peaks were probably Advanced Gewnvsronmental,Inc