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I 15 November 2004 AGE-NC Project No 96-0229 Page 5 of 6 as 16,000 gg/l (xylene, MW-2), the highest benzene concentration was detected in sample MW-1 at a concentration of 3,700 gg/l MTBE was detected by EPA Method 8260 in sixteen ground water samples collected from wells MW-1 through MW-4, MW-6, MW-7, MW-9, MW-10B, MW-11, MW-12, MW-15A, MW-l6 (A-C), MW-18B, and MW-19A at concentrations as high as 280 gg/l (MW-6), 1,2-DCA was detected in seven ground water samples collected from wells MW-1, MW-9, MW-10B, MW-16C,MW-17A,MW-18C,and MW-19A at concentrations as high as 110 gg/l(MW-1),TAME was detected in two groundwater samples collected from wells MW-9 and MW-10B at a maximum ' concentration of 1 8 µg11 (MW-9) EDB was detected in one ground water sample collected from well MW-16C at a concentration of 0 5 gg/l ' No other constituents of concern were detected above laboratory reporting limits in the analyzed samples Previous and current analytical results of ground water monitoring well samples are summarized in Table 3 The laboratory reports (Castle Analytical Laboratory Reference Numbers 7013 and 7014), quality assurance/quality control (QA/QC) reports and chain of custody forms are presented in Appendix B GeoTracker confirmation pages of the submitted laboratory electronic deliverable format (EDF) files are included in Appendix C 4.0. SUMMARY AND CONCLUSIONS The implications from the findings of the June 2004 ground water monitoring event are • Generally,depth to ground water at the site vaned between 31 feet and 33 feet below the tops of the well casings, ground water elevations ranged between 18 15 feet (MW-4) and 20 18 (MW-12) feet below mean sea level (Table 2) • First Zone ground water flow direction at the site inferred a net ground water flow towards the east-northeast at a hydraulic gradient of approximately 0 005 ft/ft (Figure 4), off-site towards the north and northeast(wells MW-6 through MW-12),net ground water flow was oriented more towards the northeast at hydraulic gradients between 0 004 ft/ft and 0 006 ft/ft • Second Zone ground water flow direction at the site inferred a net ground water flow direction towards the east-northeast at hydraulic gradients of approximately 0 003 ft/ft (Figure 5) • Due to the low hydraulic gradient at the site, slight variations in ground water recharge/discharge could greatly modify the inferred ground water flow direction • The most intense TPH-g-impacted groundwater was reported in the area of First Water Zone wells MW-2 and MW-6 at concentrations as high as 100,000 gg/l (Figure 6) Advanced CeoEnvironmental,Inc