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20 July 2007 AGE-NC Project No. 01-0886 Page 3 of 4 3.2. ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in all three monitoring wells at concentrations of 300 micrograms per liter(µg/1: MW-1), 120 pg/1 (MW-2), and 100 µg/l (MW-3). MTBE was detected in wells MW-1 through MW-3 at concentrations of 120 gg/l, 42 µg/1, and 29 µg/1, respectively. The lead scavenger 1,2-DCA was detected in wells MW-1 through MW-3 at concentrations of 150 µg/1, 7.5 µg/1, and 4.1 µg/1, respectively. The estimated distribution of dissolved 1,2-DCA is illustrated on Figure 4. EDB was detected in well MW-1 at a concentration of 2.1 µg/1. No other analytes were detected at or above laboratory detection limits in the ground water samples analyzed. The analytical results of the ground water samples collected on 12 March 2007 are summarized in Table 2. The laboratory report (CTEL Project No. CT214-0703099), quality assurance/quality control (QA/QC)report, and chain of custody form are included in Appendix C. Laboratory electronic deliverable format(EDF) files and ground water data were QA/QC checked and uploaded to the state GeoTracker database; confirmation numbers are 5952517628 and 5010114908. 4.0. SUMMARY AND CONCLUSIONS Based on the data collected from the site, AGE concludes: • At the time of the March 2007 sampling event,depths to ground water ranged from 57.00 to 57.53 feet below the well heads. Ground water elevation at the site ranged from 26.67 feet to 26.93 feet below mean sea level (MSL) and averaged approximately 26.80 feet below MSL, indicating an increase in average ground water elevation of approximately 1.68 feet since the last ground water monitoring event in December 2006. Graphs illustrating trends in depth to ground water measurements and ground water elevation are included in Appendix D. • Ground water at the site was inferred to be flowing toward the east-northeast under a calculated hydraulic gradient of approximately 0.005 ft/ft. • TPH-g was detected in wells MW-1 through MW-3 at concentrations of 300 µg/1, 120 µg/1 and 100 gg/1, respectively. MTBE was detected in wells MW-1 through MW-3 at concentrations of 120 µg/1,42 µg/1,and 29 µg/1,respectively. The lead scavenger 1,2-DCA was detected in wells MW-1 through MW-3 at concentrations of 110 µg/l, 3.2 µg/l, and 5.1 µg/1, respectively. EDB was detected in well MW-1 at a concentration of 2.1 µg/1. • The concentrations of TPH-g, MTBE and 1,2-DCA all increased in well MW-1. Graphs illustrating concentration trends of TPH-g, MTBE, and 1,2-DCA in the wells are included Advanced GeoEnvironmental,Inc.