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30 January 2004 <br /> AGE-NC Project No 96-0232 <br /> Page 2 of 15 <br /> 2.4 GROUND WATER PUMP AND TREAT REMEDIATION SYSTEM <br /> Between 15 September and 27 October 2003 and between 06 November and 09 December 2003 <br /> (fourth quarter 2003),a ground water pump-and-treat remediation system was in operation at the site <br /> Ground water pump-and-treat operations were temporarily suspended between 27 October and 06 <br /> November 2003 due to a malfunction in the process pump of the pump-and-treat system Ground <br /> water pump-and-treat operations were restarted on 06 November 2003 following repairs to the <br /> process pump Groundwater pump-and-treat operation and maintenance procedures for the site were <br /> outlined in AGE's Final Remediatton Plan, dated 31 August 2000 <br /> 2 1 GROUND WATER PUMP AND TREAT OPERATION <br /> The Flag City Chevron ground water pump-and-treat system was designed to operate at a maximum <br /> flow rate of 25 gallons per minute(GPM) During the fourth quarter,on-site extraction wells EW-4, <br /> EW-5, EW-7 and EW-8 were adjusted at each well-head to continuously extract ground water at a <br /> flow rate of approximately 5 to 6 GPM <br /> • During the fourth quarter, all extracted ground water was routed through a ground water treatment 1 <br /> system consisting of coconut shell, liquid phase granular activated carbon (GAC) Following <br /> treatment, water was discharged to a conveyance ditch(located approximately 450 feet south of the <br /> site) at a flow rate of approximately 24 to 25 GPM Field notes of ground water pump and treat <br /> operation and maintenance activities are in Appendix A <br /> Based on effluent flow meter readings (Appendix A, Table 8) during the fourth quarter 2003, <br /> approximately 1,109,431 gallons of Flag City Chevron treated ground water were discharged to the <br /> above referenced conveyance ditch under RWQCB General Order 5-00-119 for discharge to surface <br /> waters of groundwater from cleanup ofpetroleum fuel pollution Since initiation of the groundwater <br /> pump-and-treat remediation system on 20 November 2000, a total volume of approximately <br /> 23,535,076 gallons of MTBE-impacted water has been treated and discharged to the conveyance <br /> ditch under RWQCB waste water discharge permit no CAG915001 [National Pollutant Discharge <br /> Elimination System (NPDES)] <br /> 22 GROUND WATER PUMP AND TREAT SAMPLING PROCEDURES <br /> In accordance with RWQCB Monitoring and Reporting Program No 5-00-119,monthly sampling <br /> of influent and effluent waters from the pump-and-treat system and receiving water was required for <br /> analysis for petroleum constituents of concern In addition, a water sample from the effluent stream <br /> of the pump-and-treat system was required quarterly for bioassay analysis <br /> Advanced GeoEnvironmental,Inc <br />