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' 13 June 2003 • AGE-NC Project No 97-0249 ' Page 6of8 estimated extent of dissolved MTBE in Hydrologic Units 1 and 2 are depicted in Figures 10 and 11, ' respectively ' No other fuel components were detected in the ground water samples Previous and current analytical results of ground water monitoring well samples are summarized in Tables 3 and 4 The laboratory reports(McCampbell Analytical Inc Work OrderNos 0303442 and 0303476)and chain-of-custody ' forms are presented in Appendix B Analytical ground water data for the Flag City Chevron's(6421 Capitol Avenue) monitoring events are included in Appendix C ' 4 0. SUMMARY AND CONCLUSIONS ' The implications from the March 2003 ground water monitoring event are as follows • Generally, depth to ground water at the site varied between 9 and 12 feet bsg, ground water ' elevations range between 2 17 feet (MW-9A/13) and 2 62 feet (MW-10F) below mean sea level Ground water in Hydrologic Unit 1 was inferred to be east on-site and radially inward 10 " towards a ground water depression in the area of Flag City Chevron wells MW-1, MW-2, MW-4 and MW-7 at a gradient of 0 001 ft/ft or less (Figure 3) Hydrologic Units 2 and 6 ' were inferred have an east to eastward ground water flow direction at the Three B's Truck Plaza site and a more pronounced southeast component at the Rocky's Restaurant and Flag City Chevron sites at a gradient of 0 001 ft/ft or less Hydrologic Units 3 and 4 ground water were inferred to have an eastward component at an estimated gradient of 0 001 ft/fl 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 • The average increase in ground water elevation of approximately 1 8 feet between December 2002 and March 2003 may be due to seasonal fluctuation • The most intense TPH-g impacted ground water was reported in the area of wells MW-2 and MW-3 at concentrations as high as 38,000 �tg/l and in the area of MW-6 at a concentration of 16,000 µg/1 (Figure 8) • The most intense TPH-d impacted ground water was reported in the area of wells MW-8A ' and MW-3 at concentrations as high as 6,200 gg/1 and in the area of MW-6 at a concentration of 1,100 µg/l (Figure 9) • The most intense on-site MTBE-impacted ground water was detected from Hydrologic Unit 1 in the in the area of Flag City Chevron well MW-16 and Three B's Truck Plaza wells MW-4 and MW-8A at concentrations as high as 91 µg/l(Figure 10), from Hydrologic Unit 2 Advanced GeoEnvlronmental,Inc