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12 April 2006 AGE-NC Project No. 97-0301 Page 4 of 7 flow direction at the former UST location was generally northeast, in accordance with the former ' flow directions. ' 3.2. LABORATORY RESULTS OF GROUND WATER SAMPLES j I ' A total of twenty-five (25) ground water samples were submitted to CTEL for analysis. TPH-g was detected from wells MW-1, MW-7, MW-9A and MW-10A at concentrations ranging from 190 micrograms per liter (µg11) (MW-9A) to 53,000 µg11 (MW-7).The estimated extent of dissolved TPH-g in First Water Zone is depicted on Figure 5.-,TPH-d was detected in the samples collected from wells MW-1 and MW-7 at concentrations of 9,800µg11 and 24,000µg11,respectively. For the tenth consecutive quarterly monitoring event,TPH-k, and TPH-mo were not detected from any of the twenty-five water samples.analyzed. Various BTEX constituents were detected in the samples collected from wells MW-1, MW-7, MW-9A and MW-l0A at concentrations as high as 21,000 µg/1 benzene,250 µg/1 toluene,2,900 µg/1 ethylbenzene,and 5,600 µg11 total xylenes(all in the sample from MW-7). r ' 1,2-DCA was detected from wells MW-1,MW-7,MW-9A and MW-l0A at concentrations ranging from 3.9 µg/1 (MW-1OA)to 380 µg/l (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 well MW-7 only ' at a concentration of 250 µg11. 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. CT214-0512155) 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 tThe implications from the 4`h Quarter 2005 ground water monitoring event are as follows: • Generally, depth to ground water at the site varied between 33.85 feet and 35.53 feet bsg; ground water elevations ranged between 21.63 feet (MW-8A) and 22.66 feet (MW-11C) below MSL. • Ground water flow direction for the area bound by First Water Zone wells MW-1 through ' MW-12.was inferred to-be northeast from the former UST area at an approximate gradient • of 0.004 ft/ft(Figure 4). Due to the low gradient at the site,slight variations in ground water ' Advanced GeoEnvironmental,Inc. a