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, l Groundwater Pumping Test Results Report • Flag City New West#1003,6437 West Banner Street,Lodi,California Page 4 Groundwater Pumping Tests Results Water levels at monitoring points showed influence during pumping and recovery conditions The pre-test data showed fluctuating water elevations before the start of the groundwater pumping test During the pumping test, water levels dropped in all wells with pressure transducers 0 09 to 0 50 feet during the first 26 35-hour test Data(Table 3) compiled after the first test was terminated, provided evidence that recovery at well EW-3 was fast Maximum draw down at well EW-3 during the pumping test was 13 1-feet (Figure 3) Full recharge(95%) at well EW-3 was achieved in approximately 3-mmutes after the pump was turned off(Figure 3) Manual water level recovery data collected between the two tests (Table 2) shows water levels recovered from 0 03 to 0 09 feet dunng the test at wells MW-1, MW-2, MW-4A, MW-4B, and EW-5 Water levels recorded at the start of the second test in extraction well EW-3, the pumping location, showed a sudden drawdown and a steady state was achieved within the first 7-minutes of the test (Table 3 and Figure 3) at the pumping rate of 9 8 gpm, the maximum the system pump would allow The Chevron site remediation well was reportedly pumping at approximately 4 gpm • All wells were slightly influenced during the pumping test with the exception of wells MW-5A and B, MW-6B and C which are located 360 feet and 380 feet, respectively from well EW-3 CONCLUSIONS Based on groundwater level data recorded during the pumping tests, the data results are not conclusive because the aquifer was not stressed enough dunng the tests Well EW-3 only depressed the aquifer 131 feet at a flow rate of 9 8-gpm As seen in the pre-test data recovered from the pressure transducers, water levels measurements fluctuated up to 0 20-feet under static conditions (Appendix C) The fluctuations in water levels were due to barometric pressure changes affecting the transducers or regional groundwater fluctuations However,based on pressure transducer and manual depth to water measurements collected during the test, drawdown and recovery were apparent (Appendix C) For example, post-test data shows recovery occurring immediately after the pumps were turned off, making barometric pressure or regional groundwater fluctuation influence not likely Apex prepared a distance drawdown graph (Appendix D) which shows a radius of influence of 130 feet. However, wells MW-4A and MW-4B, which are located 204 feet away, did show influence The radius of influence appears to be greater than 204-fect but less than 360—feet (distance from well EW-3 to well MW-5A) The distance drawdown and a time drawdown •