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15 November 2005 • AGE-NC Project No 95-0167 Page 3 of 4 32 ANALYTICAL RESULTS OF GROUND WATER SAMPLES ' During the June 2005 ground water monitoring event,TPH-g was detected in ground water samples collected from monitoring wells MW-1 and MW-2 at a concentrations of 22,000 micrograms per liter(µg/1) and 290 µg11, respectively BTEX compounds were detected in the ground water samples collected from monitoring wells MW-1 and MW-2 at concentrations of 4,600 µg/1 benzene,2,600µg/1 toluene,55 µg/1 ethylbenzene, and 3,850 µg/1 total xylenes in MW-1, and 56 µg/1 benzene, 1 I µg/1 toluene, 31 µg11 ethylbenzene, ' and 93 7 gg/1 totoal xylenes in MW-2 Fuel additive t-Amyl Methyl Ether (TAME) was detected in MW-1 at a concentration of 130 µg/1, ' and additive 1,2-Dichloroethane(1,2-DCA)was detected in MW-1 and MW-2 at concentrations of 70 µg/1 and 2 3 pg/l, respectively ' Analytical results of ground water samples collected during the June 2005 monitoring event are summarized in Table 2 Figure 4 illustrates the estimated lateral distribution of dissolved TPH-g at the site The laboratory report(CTEL Project No CT214-0506261),quality assurance/quality control Ile (QA/QC) report, and chain of custody forms are included in Appendix C Documents confirming the upload of laboratory electronic deliverable format(EDF)files and depth to water measurements to GeoTracker are included in Appendix D 4.0. SUMMARY AND CONCLUSIONS • On 29 June 2005, depths to ground water ranged from 13 89 to 14 73 feet below the tops of ' the well casings Ground water elevations at the site averaged approximately 3 08 feet below mean sea level (MSL), indicating an average elevation decrease of 0 1 feet since the last monitoring event in March 2005 • Ground water flow was determined to be towards the east-northeast under an average hydraulic gradient of 0 0025 ft/ft • TPH-g was detected in ground water samples collected from monitoring wells MW-1 and MW-2 at concentrations of 22,000µg/1 and 290 pg/l, respectively BTEX compounds were detected in the ground water samples collected from monitoring wells MW-1 and MW-2 at maximum concentrations of 4,600 gg/l benzene, 2,600 gg/I toluene, 55 µg/l ethylbenzene, and 3,850 gg/l total xylenes in MW-1 Y ' The lateral extent of petroleum hydrocarbon contamination is fully defined as of this quarter's monitoring event to the west by well MW-3,to the south by MW-7,to the cast by . well MW-5, and to the northeast by MW-6 r .4dvuncerl GeoEnviroumental,Inc 1