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31 March 2005 AGE-NC Project No 97-0249 ' Page 6 of 8 ' (MW-8A) The estimated extent of dissolved MTBE in Hydrologic Units 1 and 2 are depicted on Figures 11 and 12, respectively t TBA was detected in ground water samples MW-1,MW-2 and MW-8A at maximum concentrations of 190 µg/1, 1,2-DCA was detected in ground water samples MW-3 and MW-I OA at concentrations of 27 µg/l and 5 9 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 Analytical ground water data for the Flag City Chevron's monitoring events are included in Appendix A The laboratory reports (MAI Work Orders 0412541 and 0412559),quality assurance/quality control(QA/QC)reports and chain ' of custody forms are presented in Appendix C , 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 December 2004 ground water monitoring event are as follows Generally, depth to ground water at the site varied between 11 feet and 14 feet bsg, ground water elevations ranged between 1 07 feet (MW-9B) and 16 6 feet(MW-I OF)below mean sea level • Ground water data collected from Hydrogeologic Units I through 6 at both the Three B's Truck Plaza and the Flag City Chevron site's inferred a net ground water flow direction I towards the east-southeast (Figures 4 through 8) • The most intense TPH-g-impacted ground water was reported from Hydrologic Unit I in the area of wells MW-1, MW-2, MW-3, MW-6, MW-8A and MW-IOA, at concentrations as high as 24,000 µg/1 (Figure 9) • The most intense TPH-d-impacted ground water was reported from Hydrologic Unit 1 in the area of wells MW-3 and MW-8A at a concentration as high as 2,700 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 1 in the area of Three B's Truck Plaza well MW-8A at a concentration of 48 µg/1 and from Flag City Chevron well MW-16 at a concentration of 42 µg11 Other on-site MTBE detections were from Hydrologic Unit 2 in the area of Flag City Chevron well MW-17 at a . concentration of 100 µg/l (Figure 12) and from Hydrologic Unit 3 in the area of Flag City Advanced GeoEnvnronmental,Inc 1