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1 11 August 2003 AGE-NC Project No 96-0232 tPage 2 of 15 ' 2 1 GROUND WATER PUMP AND TREAT OPERATION The Flag City Chevron ground water pump-and-treat system was designed to operate at a maximum ' flow rate of 25 gallons per minute(GPM) During the second 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 ' During the second quarter 2003, all extracted ground water was routed through a ground water treatment system consisting of granular activated carbon (GAC) and Sunsolve® Following ' treatment,water was discharged to a conveyance ditch(located approximately 450 feet south of the site) at a flow rate of approximately 2425 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 second quarter 2003, ' approximately 2,090,669 gallons of Flag City Chevron treated ground water were discharged to the above 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 liepump-and-treat remediation system on 20 November 2000, a total volume of approximately 21,589,805 gallons of MTBE-impacted water has been treated and discharged to the conveyance ditch under RWQCB waste water discharge permit no CAG915001 [National Pollutant Discharge Elimination System (NPDES)] 2 2 GROUND WATER PUMP AND TREAT SAMPLING PROCEDURES In accordance with RWQCB Monitoring and Reporting Program No 5-00-119,monthly sampling of influent and effluent waters from the pump-and-treat system and receiving water was required for analysis for petroleum constituents of concern In addition,a water sample from the effluent stream of the pump-and-treat system was required quarterly for bioassay On 21 April, 14 May and 25 June 2003, samples of ground water were collected from valved sampling ports located pre-treatment(influent) and post-treatment(effluent)of the pump-and-treat system In addition,water samples were collected from the receiving water sampling stations located in the conveyance ditch approximately 50 feet upstream(R-1)and 80 feet downstream(R-2) of the point of discharge, R-1 and R-2 locations were approved by the RWQCB during a site inspection Ion 22 November 2000 The grab water samples were collected from influent,effluent and receiving water locations utilizing Miter amber bottles and 1-gallon plastic lugs without a sample preservative and 40-m1 EPA- approved VOA vials containing 0 5 ml 18% hydrochloric acid as a sample preservative Care was I Advanced GeoEnvironmental,Inc