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S CAMBRIAN an extraction rate of approximately 10 gpm This pumping rate was maintained for 60 minutes until the water table stabilized at 56 42 fbg A third step was performed at an extraction rate of approximately 2 0 gpm This pumping rate was maintained for 10 minutes until the pumping well nearly dewatered Groundwater recharge was monitored for 25 minutes until 80% of the water column recovered Field data sheets are provided in Appendix A Constant Rate Test Results Based on the results of the step dischar a test, Cambria elected to conduct the constant rate test at an extraction rate of approximates 0 8 gpm This flow rate was maintained for 5,504 minutes (91 73 hours) Note the entire test was 5,717 minutes (95 28 hours) A total of 4,248 5 gallons of groundwater were extracted from MW-4 over the duration of the test Table le presents the pump test extraction data, analytical results of groundwater samples,and mass removal data The initial groundwater sample collected from MW-4 on October 21, 2002 contained 130,000 ppb MTBE The subsequent groundwater sample collected from MW-4 on October 21, 2002 contained 98,000 ppb MTBE Groundwater samples collected from MW-4 on October 22, 23, 24, and 25, 2002 contained MTBE at 110,000 ppb, 88,000 ppb, 77,000 ppb, and 79,000 ppb,respectively The certified analytical report is provided as Appendix B r Pump Test Analyses: The d cted demonstrated that the sustainable pumping rate for well MW-4 was approximate) 7 gpm oundwater drawdown was observed in piezorneters P-1 and P-2, however it's magnitude was too small to allow for analysis for the recovery data Therefore, Cambria was limited to analyzing the recovery data from the pumping well Cambria analyzed the recovery data using AquiferTest for Windows° version 3 01 software from Waterloo Hydrogeologic, Inc Appendix C presents the pump test analysis reports Recovery data from the test was analyzed by the Theis Recovery method to estimate transmissivity and hydr ul conductivity Cambria estimated the hydraulic conductivity of this unconfined con ed aquifer to be 0 122 meters/day based on the recovery data from the step discharge test, and 0 0944 meters/day based on the recovery data from the constant rate test The hydraulic conductivities yielded from the recovery data analysis are within the range of silt and fine sand (Todd, 1980) which correlates well with the soil types logged for this well (sand and silty sand) CONCLUSIONS The extended aquifer pump test data suggest that interim remediation was effective As previously stated, 4,248 5 gallons of groundwater were extracted over the five day period Based 0955 5