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' 25 January 2005 AGE-NC Project No 97-0301 ' Page 4 of 6 32 LABORATORY RESULTS OF GROUND WATER SAMPLES A total of twenty-six (26) ground water samples were submitted to CTEL for analysis ' TPH-g was detected in two water samples collected from wells MW-1 and MW-7 at concentrations of 10,000 micrograms per liter (µg/1) and 31,000 µg11, respectively The estimated extent of ' dissolved TPH-g in First Water Zone is depicted on Figure 5 For the fifth consecutive quarterly monitoring event,TPH-d,TPH-k,and TPH-mo were not detected from any of the twenty-six water samples analyzed Various BTEX constituents were detected in the same water samples(MW-1 and ' MW-7)at concentrations as high as 7,200 µg11 benzene,720 µg/1 toluene, 1,700 µg/1 ethylbenzene, and 6,700 gg/l total xylenes ' MTBE was detected in one water sample collected from well MW-1 at a concentration of 40 gg/l, 1,2-DCA was detected in two water samples collected from wells MW-1 and MW-7, at concentrations of 35gg11,and 200µg/l,respectively TAME was detected in the water sample from ' well MW-7 at a concentration of 82 gg/l • 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 report(CTEL Project No CT214-0410014) and chain of custody forms are presented in Appendix B, GeoTracker confirmation pages of the submitted laboratory electronic deliverable format(EDF) I ' files are included in Appendix C ' 4 0 SUMMARY AND CONCLUSIONS ' The implications from the 3`d Quarter 2004 ground water monitoring event are as follows Generally,depth to ground water at the site vaned between 3 5 70 and 37 50 feet bsg,ground ' water elevations ranged between 23 31 feet(MW-1 OA&B)and 24 91 feet(MW-12D)below MSL • Ground water flow direction for the area bound by First Water Zone wells MW-1 through ' MW-12 was inferred to be east-northeast at an approximate gradient of 0 002 ft/ft or less (Figure 4) Due to the low gradient at the site, slight variations in ground water ' measurements or changes of recharge/discharge of the local ground water could greatly modify ground water flow direction • The average ground water elevation at the site on 30 September 2004 was 24 06 feet below ' MSL Generally, ground water elevation at the site decreased an average 2 68 feet between the June 2004 and the September 2004 ground water monitoring events The decrease in I Advanced GeoEnvironmental,Inc