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' 15 January 2006 • AGE-NC Project No 04-1045 ' Page 3 of 4 ' All BTEX compounds were detected in ground water samples collected from wells MW-1 through MW-3,the maximum BTEX concentrations were detected in well MW-1 at concentrations of 13,000 µg/1 benzene, 85,000 µg11 toluene, 16,000m µg/l ethylbenzene and 79,000 µg/l total xylenes 1 ' The fuel additives 1,2-DCA and TAME were detected in the ground water sample collected from well MW-1 at concentrations of 350 µg/1 and 120 �tg/l, respectively ' No other analytes were detected at or above laboratory reporting limits in the analyzed ground water samples The analytical results of the ground water samples collected on 04 November 2005 are ' summarized in Table 2 Maps depicting the distribution of benzene and TPH-g contamination are shown on Figure 4 and Figure 5 The laboratory report(CTEL Project No CT214-0511042),QA/QC reports 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 November 2005 monitoring event, ground water was inferred to flow towards the southeast at a gradient of 0 079 ft/ft,which appears to be a slight aberration from the generally northeasterly flow in the area Due to the low hydraulic gradient at the site on 04 November 2005, slight variations in ground water measurements or changes of recharge/discharge of the local ground water could greatly modify the inferred ground water flow direction • TPH-g was detected in all wells,at a maximum concentration of 220,000µg/1 in MW-1 The TPH-g concentration was the highest detected since monitoring began in November 2004 TPH-g has not been detected in MW-2 and MW-3 since February 2005 • All BTEX compounds were detected in ground water samples collected from wells MW-1 through MW-3, at maximum concentrations of 13,000 µg/1 benzene, 85,000 µg/1 toluene, 16,000 µg/l ethylbenzene and 79,000 µg/l total xylenes from well MW-1 • 1,2-DCA and TAME were detected only in the ground water sample from MW-1, at Econcentrations of 350 µg11 and 120 [g/l, respectively • The concentrations of BTEX compounds and 1,2-DCA detected in well MW-1 exceed California DHS' Maximum Contaminant Levels for these compounds in drinking water • Additional assessment is necessary to further define the vertical and lateral extent of soil and • ground water contamination in the former UST area .� Advanced GeoEavironmental,Inc