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Groundwater Pumping Test Results Report Flag City New West#1003,6437 West Banner street,loth,California Page 3 January 9, 2006-The SJCEHD issued a letter requiring clarity as to the owner and operator of the site for the clean up fund, stating additional sampling was needed for the NPDES permit, requiring Apex to conduct a groundwater pumping test, and to evaluate other remedial alternatives (Appendix A) GROUNDWATER PUMPING TESTS Apex conducted two groundwater pumping tests utilizing well EW-3 The initial test ran for 26 35 hours and the system was shut down allowing well EW-3 to recover The second test was started and allowed to run for approximately 1 hour Apex personnel collected manual depth-to- water measurements to the nearest 0 01 foot, referenced to the surveyed top-of-casing elevations, and performed according to the Apex SOP included as Appendix B Field Activities On February 13, 2006, static groundwater levels were collected manually from wells MW-3A, MW-3B, EW-1, EW-2, EW-3, and EW-4 (Table 1) Apex personnel installed pressure transducers in monitoring locations MW-3A, MW-3B, EW-1, EW-2, and EW-4 The transducers were turned on at 12 00 PM and ran for the remainder of both tests, collecting water level data at 1 hour intervals for the first 24-hours and 15-minute intervals there after On February 15, 2006, the first groundwater pumping test was initiated at 10 35 AM by starting the pump in well EW-3 The pump operated for approximately 26 35-hours during the test The flow rate was adjusted at start up from the initial flow rate of 7-gallons per minute (gpm) to 9 8- gpm (the maximum flow rate for the pump) within the first hour of the test The system was shut off on February 16, 2006 at 1 10 PM and recovery data was collected from well EW-3 The well was allowed to recover to static conditions which took 31-minutes On February 16, 2006, the second groundwater pumping test was initiated at 3 41 PM and ran for 0 59-minutes The second test was terminated and recovery data from well EW-3 and monitoring wells MW-2, MW-4A, MW-4B, MW-5A, MW-5B, MW-6B, MW-6C, and EW-5 were collected The pressure transducers continued to collect data for approximately 16-hours after the second test was terminated Groundwater level measurements collected manually from extraction well EW-3 and surrounding extraction and monitoring wells without pressure transducers during the pumping test are summarized in Tables 2 through 4 Groundwater level measurements collected from the monitoring wells containing the pressure transducers were converted to groundwater elevations and are presented in Appendices B and C in graphical and tabular format (Figures B-1 through B- 5 and Tables C-1 through G5, corresponding to wells EW-1, EW-2, EW-4, MW-3A, and MW- 3B, respectively)