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21 June 2004 S AGE-NC Project No 97-0249 IPage 6 of 7 TBA was detected in 1 ground water samples collected from well MW-11D at a concentration of 6 4 µg/l, 1,2-DCA was detected in 5 ground water samples collected from wells MW-2, MW-3, MW-6, MW-10A and MW-11 A at concentrations as high as 18 µg/1 INo 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 Order Nos 0403274,0403291 and 0403315)and cham- Iof-custody forms are presented in Appendix C Analytical ground water data for the Flag City Chevron's monitoring events are included in Appendix A I4.0. SUMMARY AND CONCLUSIONS ' The implications from the March 2004 ground water monitoring event are as follows • Generally, depth to ground water at the site varied between 7 feet and 11 feet bsg, ground ' water elevations ranged between 0 57 feet (MW-9B) and 127 feet (MW-10F) below mean sea level '• • Ground water from Hydrologic Unit I at the at the Flag City Chevron was inferred to have a radially inward flow direction towards a ground water depression in the area of Flag City Chevron wells MW-1,MW-2 and MW-4, and was inferred to be towards the east-northeast at the Three B's Truck Plaza c Ground water from Hydrologic Unit 2 inferred a net ground water flow towards the east- northeast at hydraulic gradients of 0 003 ft/ft or less However,ground water flow direction ' at the Three B's Truck Plaza was inferred radially inward towards a ground water depression in the area of Three B's Truck Plaza well MW-9A and the domestic water well (Figure 5) Ground water from Hydrologic Units 3 and 4 at the Three B's Truck Plaza and Flag City Chevron were inferred to be towards the east (Figures 6 and 7) • Ground water from Hydrologic Unit 6 at the Three B's Truck Plaza and Flag City Chevron ' were inferred to be towards the south-southeast (Figures 8) • The most intense TPH-g impacted ground water was reported from Hydrologic Unit I in the ' area of wells MW-2,MW-3 and MW-6, at concentrations as high as 21,000 gg/1(Figure 9) • The most intense TPH-d impacted ground water was reported from Hydrologic Unit I in the area of wells MW-1 and MW-3 at concentrations as high as 3,200 µg/1 (Figure 10), an isolated TPH-d occurrence was reported at Flag City Chevron well MW-12A,approximately 200 feet southeast of the site • The most intense on-site MTBE-impacted ground water was reported from Hydrologic Unit I in the in the area of Three B's Truck Plaza well MW-8A at a concentration of 64 gg/1 • and from Flag City Chevron well MW-16 at a concentration of 76 µg/1 (Figure 11), from ' Hydrologic Unit 2 in the area of Flag City Chevron well MW-17 at a concentration of Advanced GeoEnvironmental,Inc