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22 November 2011 AGE-NC Project No. 09-1692 Page 2 of 3 No additional analytes were reported above laboratory detection limits in the ground water samples analyzed. Analytical results of water samples collected in September 2011 are summarized on Table 3. The laboratory report (CTEL Lab Project No. CT214-1109152), quality assurance/quality control report, and chain-of-custody form are included in Appendix D. The laboratory report electronic data file (EDF) and depth to water data was uploaded to the State Water Board's Geotracker database; the confirmation numbers are 3452717602 and 1213866472. 4.0. SUMMARY AND CONCLUSIONS Based upon the results of this quarterly monitoring event, AGE concludes: • During the September 2011 monitoring event, depths to ground water at the site ranged from 13.28 feet to 14.90 feet btoc, and averaged approximately 13.30 feet btoc. Ground water elevation average approximately 5.19 feet below the NAVD88, a decrease of approximately 0.8 feet since the June 2011 ground water monitoring event. • Consistent with past monitoring events, the ground water was inferred to be flowing radially towards a ground water depression centered at well MW-4, at hydraulic gradients of 0.003 ft/ft and 0.004 ft/ft (Figure 3). • During the September 2011 ground water monitoring event, TPH-d were reported in the ground water samples collected from wells MW-2 and MW-4 at concentrations of 290 micrograms per liter (Ng/1) and 260 pg/I, respectively. The lateral extent of dissolved TPH-d is illustrated in Figure 4. • TPH-d concentrations in wells MW-2 and MW-4 decreased approximately 61% and 49%, respectively between the June 2011 and the September 2011 ground water monitoring events. Graphs illustrating TPH-d concentration trends in wells MW-2 and MW-4 are included in Appendix E. 5.0. RECOMMENDATIONS Based on the findings of the environmental activities recounted in this report, AGE recommends: • Continuation of the ground water monitoring program in accordance with CVRWQCB requirements; but limited to one additional sampling event to conclude an annual monitoring cycle. The next ground water monitoring event is scheduled in December 2011. Advanced GeoEnvironmental,Inc.