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16 September 2004 • AGE-NC Project No 97-0249 IPage 6 of 8 Various BTEX constituents were detected in 19 water samples collected from wells MW-1,MW-2, MW-3, MW-5, MW-6, MW-7 (A and B), MW-8 (A-F), MW-9 (A and C) and MW-10 (A-D) at concentrations as high as 4,700µg/1 benzene,460µg/l toluene,710µg/1 ethylbenzene and 2,400µg/1 ' xylenes in the sample collected from MW-3 The greatest benzene-impact was also detected in the ground water sample collected from well MW-3 at a concentration of 4,700 µg/1 ' MTBE was detected by EPA Method 8260 in 13 ground water samples collected from wells MW-1, MW-2, MW-4, MW-6, MW-8 (A), MW-9 (A and B), MW-10 (A-C) and MW-11 (A-C) at concentrations as high as 130 µg/1 (MW-8A) The estimated extent of dissolved MTBE in ' Hydrologic Units 1 and 2 are depicted in Figures 11 and 12, respectively TBA was detected in 1 ground water samples collected from well MW-5 at a concentration of 14 ' µg/1, 1,2-DCA was detected in 2 ground water samples collected from wells MW-10A and MW-11 A at concentrations of 8 5 µg/1 and 18 µg/l, 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,analytical results . for the domestic water well sample are summarized in Table 5 The laboratory reports(McCampbell Analytical Inc Work Order Nos 0406264 and 0406291) and chain-of-custody forms are presented in Appendix C Analytical ground water data for the Flag City Chevron's monitoring events are included in Appendix A, GeoTracker confirmation pages of the submitted laboratory electronic ' deliverable format (EDF) files are included in Appendix D ' 4.0. SUMMARY AND CONCLUSIONS The implications from the June 2004 ground water monitoring event are as follows • Generally, depth to ground water at the site vaned between 11 feet and 14 feet bsg, ground ' water elevations ranged between 176 feet(MW-11B)and 2 34 feet(MW-10F)below mean sea level • Ground water data collected from Hydrologic Units 1 through 6 at the Three B's Truck Plaza inferred a net ground water flow towards the east-northeast, ground water flow direction at the Flag City Chevron site was inferred towards the east-southeast (Figures 4 through 8) • The most intense TPH-g impacted ground water was reported from Hydrologic Unit I to the area of wells MW-2, MW-3, MW-6 and MW-8A, at concentrations as high as 27,000 µg/1 (Figure 9) ' • The most intense TPH-d impacted ground water was reported from Hydrologic Unit 1 in the . area of well MW-3 at a concentration of 2,500 µg/1 (Figure 10), an isolated TPH-d 1 Advanced GeoEnvironmental,Inc I