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I ' 25 March 2004 AGE-NC Project No 97-0249 ' Page 2 of 7 At the request of the CRWQCB-CVR,ground water monitoring events performed at the Three B's ' Truck Plaza site and the Flag City Chevron site (6421 Capitol Avenue) have been coordinated to occur concurrently, the Flag City Chevron ground water monitoring and analytical results are ' included in Appendix A ' 2 1 WELL MONITORING AND EVACUATION On 08 December 2003, depth to ground water was measured in each well from the top of the well casing to the nearest 0 01-foot utilizing a Sohnst water level meter On 08, 09 and 10 December 2003, approximately 5'/z to 7 gallons of ground water (a minimum of three casing-water volumes per well) were evacuated (purged) from wells MW-1 through MW-6 utilizing disposable polyethylene bailers Temperature, p14 and conductivity were measured for stabilization at regular purge-volume intervals from each well using an Oakton water analyzer Field I data and logs are provided in Appendix B Purged ground water was containerized in 55-gallon drums and stored on-site in an area lacking general public access Multi-level monitoring wells MW-7 through MW-12 were purged by lowering and raising a 3/8-inch outer diameter, length-discrete polyethylene hose equipped with a ball-valve water tip through the top chambers into the specific water-charged screened section A Watera-Hydro-Lift H pump equipped with a mechanical arm was utilized to surge each well with a polyethylene hose Approximately 3/4 to 4%z gallons of ground water (a minimum of three casing-water volumes per well)were purged from each well Temperature,pH and conductivity were measured for stabilization I at regular purge-volume intervals from each well using the Oakton water analyzer Field data and logs are in Appendix B Multi-level well purged ground water was transferred to 55-gallon drums and stored on-site in an area lacking general public access 2 2 GROUND WATER SAMPLING After each well was purged,groundwater levels were measured to venfy the amount of ground water recharge Upon achieving at least 80% ground water recharge, samples were collected from wells MW-1 through MW-12 utilizing the techniques described above in purging each well,however,80% recharge was not achieved from wells MW-8A and MW-8C due to a combination of water drawn- down nearly to the bottom of the screen section and slow recharge Ground water samples were transferred into 40-m1 EPA-approved volatile organic analysis(VOA)vials containing 0 5 ml 18% hydrochloric acid as a sample preservative and I-liter amber bottles without sample preservative Care was taken to ensure that visible air bubbles were not present in the vials after filling and capping Ground water sample containers were labeled with the well designation, date, time, and • sampler's initials IAdvanced GeoEnvironmentaI,Inc