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I04 November 2005 . AGE-NC Project No 02-0950 ' Page 3 of 4 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES ' TPH- and TPH-d were detected in the round water sample collected from well MW-2 at g g P ' concentrations of 8,400 micrograms per liter (µg/1) and 26,000 µg/l, respectively BTEX components were detected in the water sample collected from well MW-2 at concentrations ' of 400 µg/1 benzene, 70 µg/1 toluene, 1,500 µg/1 ethylbenzene, and 3,840 µg/1 xylenes No other analytes were detected at or above laboratory reporting limits in the ground water samples I analyzed The analytical results of the ground water samples are summarized in Table 2 Cross- section D-D' (Figure 4) was constructed to show the estimated vertical extent of petroleum hydrocarbon contamination at the site The estimated lateral extent of petroleum hydrocarbon ' contamination is illustrated on Figure 5 The laboratory report(CTEL Project No CT214-0509097), quality assurance/quality control (QA/QC) report, and chain of custody form 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 Based on the data collected from the site, AGE concludes ' • At the time of the September 2005 sampling event, depths to ground water ranged from 18 22 feet to 18 70 feet below the tops of the well casings Ground water elevation at the site ' averaged approximately 10 71 feet below MSL, indicating an overall average decrease in ground water elevation of 128 feet between June 2005 and September 2005 ' TPH-g and TPH-d were detected in the ground water sample collected from well MW-2 at concentrations of 8,400µg/1 and 26,000µg/1,respectively BTEX components were detected in the water sample collected from well MW-2 at concentrations of 400µg/1 benzene,70µg/1 ' toluene, 1,500 µg/1 ethylbenzene, and 3,840 µg/1 xylenes • The concentrations of TPH-g and toluene decreased slightly compared to the previous ' quarter, concentrations of TPH-d, benzene, ethylbenzene, and xylenes increased • The concentrations of BTEX, except for toluene, detected in MW-2 were all above each constituent's respective DHS maximum contaminant level (MCL) ' The lateral extent of the former UST petroleum hydrocarbon plume is defined to the west by well MW-3,to the north by well MW-1,to the northeast by well MW-4,and to the south by ' well MW-5 The plume is not yet defined to the southeast ' Advanced GeoEnvironmental,Inc