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' 15 October 2001 AGE-NC Project No 96-0232 ' Page 12 of 17 ' The results of pump and treat ground water remediation between 01 July and 30 September 2001 are as follows ' • Approximately 1,923,307 gallons of MTBE-Impacted ground water were selectively extracted from wells EW-2, EW-4, EW-5, EW-6, EW-7, EW-8, EW-9 and EW-10,which are completed in the First Zone aquifer ' - A total volume of approximately 7,798,723 gallons of MTBE-impacted water has been treated at the site since the start-up period in November 2000 t - Laboratory analysis of three grab water samples collected at the effluent-end of the pump and treat system did not detect any constituents of concern ' - Dissolved MTBE was detected (utilizing EPA Method 8260M) in water samples collected from the extraction wells at concentrations between 13 and 35 ug/l, the greatest MTBE- impacted water was collected from extraction well EW-5 near the west section of the site ' - Dissolved MTBE was detected from grab samples collected at the influent-end of the treatment system at concentrations between 7 and 28 µg/1 . Between 02 July and 01 August 2001, the mass of MTBE-impacted ground water processed during operation of the pump and treat system was calculated to be 6,278,203 pounds Multiplying the average MTBE concentration(23 5 µg11)by the pounds of MTBE-extracted water yielded a mass of approximately 0 14 pounds of MTBE removed from the extracted ground water (Table 8, Appendix D) - Between 01 August and 06 September 2001, the mass of MTBE-Impacted ground water processed during operation of the pump and treat system was calculated to be 3,668,572 pounds Multiplying the average MTBE concentration (13 µg/1) by the pounds of MTBE- extracted water yielded a mass of approximately 0 05 pounds of MTBE removed from extracted ground water(Table 8, Appendix D) - Between 06 September and 01 October 2001, the mass of MTBE-impacted ground water processed during operation of the pump and treat system was calculated to be 6,087,836 pounds Multiplying the average MTBE concentration (7 µgll) by the pounds of MTBE- extracted water yielded a mass of approximately 0 04 pounds of MTBE removed from extracted ground water (Appendix D) ' The results from the ground water monitoring and sampling events performed in September 2001 are as follows - Generally, depth to ground water at the site varied between 15 and 19 feet bsg - First Zone ground water flow direction at the site appeared to be oriented toward the area of I Advanced GeoEnvironmental,Inc