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' 30 October 2003 AGE-NC Project No 96-0232 ' Page 2 of 15 ' • 27 August 2003 -Ground water pump-and-treat operations restarted following removal and replacement (change-out) of 4,000 pounds of coconut shell, liquid phase granular activated carbon(GAC)from the 3`d(GAC-3) and 4`"(GAC-4) in-line pump-and-treat media vessels ' 15, 16& 17 September 2003 -Quarterly ground water monitoring event(third quarter 2003) at wells MW-1 through MW-18, EW-1 through EW-10, CSA-1 and CSA-2 2.0 GROUND WATER PUMP AND TREAT REMEDIATION SYSTEM ' Between 25 June 2003 and 15 September 2003 (third quarter 2003),a ground water pump-and-treat remediation system was in operation at the site However,ground water pump-and-treat operations ' were temporarily suspended between 07 and 25 July 2003 and between 04 and 27 August 2003 due to detection of MTBE at the pump-and treat effluent Ground water pump-and-treat operations were ' restarted on 27 August 2003 following a change-out of carbon media from the 3`d and 4" in-line media vessels Groundwater pump-and-treat operation and maintenance procedures for the site were outlined in AGE's Final Remediation Plan, dated 31 August 2000 I• 2 1 GROUND WATER PUMP AND TREAT OPERATION The Flag City Chevron ground water pump-anal-treat system was designed to operate at a maximum flow rate of 25 gallons per minute (GPM) During the third quarter, on-site extraction wells EW-4, EW-5, EW-7 and EW-8 were adjusted at each well-head to continuously extract ground water at a flow rate of approximately 5 to 6 GPM Prior to 27 August 2003, all extracted ground water was routed through a ground water treatment system consisting of coconut shell, liquid phase granular activated carbon (GAC) and Sunsolve®, after 27 August 2003,all extracted groundwater was routed through four 2,000 pound media vessels containing only liquid phase GAC Following treatment,water was discharged to a conveyance ditch (located approximately 450 feet south of the site) at a flow rate of approximately 24 to 25 GPM Field notes of ground water pump and treat operation and maintenance activities are in Appendix A Based on effluent flow meter readings (Appendix A, Table 8) during the third quarter 2003 approximately 835,840 gallons of Flag City Chevron treated ground water were discharged to the rabove referenced conveyance ditch under RWQCB General Order 5-00-119 for discharge to surface waters of groundwater from cleanup ofpetroleum fuel pollution Since initiation ofthe groundwater pump-and-treat remediation system on 20 November 2000, a total volume of approximately 22,425,645 gallons of MTBE-impacted water has been treated and discharged to the conveyance Advanced GeoEnvironmental,Inc I