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' 24 August 2005 . AGE-NC Project No. 97-0301 Page4of6 . 3.2. 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 from wells MW-1 and MW-7 at concentrations of 4,900 micrograms per liter (µg11) and 43,000 µg11, respectively. The estimated extent of dissolved TPH-g in First Water Zone ' is depicted on Figure 5. For the eighth 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 samples collected from wells MW-1,MW-7,MW-8A,MW-8B and ' MW-9A at concentrations as.high as 7,500 µg/1 benzene (greatest on-site benzene concentration detected MW-7), 160 µg11 toluene(MWA),2,500 µg/l ethylbenzene (MW-7), and 5,260 µg/1 total xylenes (MW-7). ' 1,2-DCA was detected from wells MW-1,MW-7, MW-9A, MW-10A,MW-iOB*and MW-10C, at concentrations ranging from 3.8 41 (MW-10B) to 49 µg11 (MW-7). The estimated extent of ' dissolved 1,2-DCA in First Water Zone is depicted on Figure 6. TAME was detected in the water samples from wells MW-l.and MW-7 at concentrations of 8.1 µg/1 and 7.3 µg/1,respectively.MTBE was detected from well MW-1 at a concentration of 25 µg/1. 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 Laboratory I.D. CT214-0506123) 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 2°a Quarter 2005 ground water monitoring event are as follows: ' Generally, depth to round water at the site varied between 30.37. feet and 32.05 feet bs ; p g g ground water elevations ranged between 18.21 feet (MW-8A) and 19.40 feet (MW-11D) below MSL. ilk f ,UL • Groundwater flow direction for the. ea ound by First Water Zone wells MW-1 through MW-12 was inferred to be'5nok om tt e�foimer UST area at an approximate gradient of ' 0.006 ft/ft or less (Figure 4). However, the water table surface has exhibited a cumulative' eastward flow. 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.' i ' Advanced GeoEnviranmental,Inc. r