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1 ' IS November 2004 • AGE-NC Project No 97-0301 ' Page 4 of 6 3 2 LABORATORY RESULTS OF GROUND WATER SAMPLES A total of twenty-six (26) ground water samples were submitted to CTEL for analysis tTPH-g was detected in two water samples collected from wells MW-1 and MW-7 at concentrations of 6,700 micrograms per liter(µg11)and 29,000µg11,respectively The estimated extent of dissolved ' TPH-g in First Water Zone is depicted on Figure 5 For the fourth 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) I ' at concentrations as high as 11,000 µg/1 benzene, 590 µg/1 toluene, 2,300 µg11 ethylbenzene, and 7,400 µg11 total xylenes Benzene was also detected in well MW-9A at a concentration of 14 µg/1 I ' MTBE was detected in one water sample collected from well MW-1 at a concentration of 3 4 µg/1, 1,2-DCA was detected in three water samples collected from wells MW-1,MW-7, and MW-9A at concentrations of 15 µg11, 260 µg11, and 35 µg11, respectively TAME was detected in the water ' sample from well MW-1 at a concentration of 6 9 µg/1 No other fuel components were detected in the groundwater 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 CT214-0404003) 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 t4.0 SUMMARY AND CONCLUSIONS The implications from the June 2004 ground water monitoring event are as follows • Generally,depth to ground water at the site varied between 33 09 and 34 88 feet bsg,ground ' water elevations ranged between 20 88 feet (MW-8A) and 22 10 feet (MW-11D) below MSL • Ground water flow direction for the area bound by First Water Zone wells MW-1 through tMW-12 was inferred to be east-northeast at an approximate gradient of 0 003 fl/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 • Ground water elevation generally decreased at the site an average 3 44 feet between the ' March 2004 and the June 2004 ground water monitoring events The decrease in ground . water elevation is probably due to seasonal fluctuation ' Advanced CeoEnvironmental,Inc