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Groundwater Well Installation Work Plan Sharpe Army Depot Lathrop, California EWC8 and EWC9, the drawdown will be observed at MW543C, MW538C, and MW540C. For extraction well EWC6, the drawdown will be observed at MW326C and MW331C. For extraction well EWC7, the drawdown will be observed at MW332C, MW326C, and MW540C. For extraction well EWCC7, the drawdown will be observed at MW514C. Discharge rates will be monitored and controlled via a flow meter and control valve installed on the discharge hose. Water level data for all tests will be collected and recorded using pressure transducers and a data logger.A manually operated water level meter will be used during the test to confirm the data collected by the transducers. Pumping test activities will include the following: 1. Decontaminate equipment placed in the well. Record the submersible pump model. 2. Install a submersible pump and pressure transducer in the pumping well.The pressure transducer and cable can be attached to the submersible pump discharge pipe using ties to prevent the transducer from becoming entangled in the well. 3. Install piping to convey the groundwater to the discharge point. Install a flow meter(with a totalizer) and valve to measure and control the discharge rate. 4. Program the test-specific information into the data logger and set it to monitor recovery at the end of the pumping portion of the test.Typical parameters (depending on the data logger selected) include test number, length, measurement intervals,frequency, and start time. 5. Place pressure transducers in each observation well, as applicable. 6. Verify the placement of each transducer in the well by checking depth readings from the transducer data logger as it is lowered below the water surface. Set the transducer at least 5 ft below the maximum drawdown anticipated in the well during pumping(approximately 60 ft in the C Zone) but above the maximum submergence depth for the transducer. 7. Secure each transducer to the well casing at the surface to prevent the transducer from moving during the test. 8. Allow each transducer to equilibrate for 3 to 5 minutes with the temperature of the well water. Then check the functioning of each transducer by moving the transducer up or down a measured distance and noting the resulting change as measured by the data logger. Compare the change to the manually measured distance to check that the pressure transducer is operating correctly. 9. Run the data logger self-test routine (if available)to check that the data logger and transducers are operating properly. If the self-test indicates that the instrument is not functioning correctly, the test will not be started, and a backup transducer will be installed. 10. Measure and record the water level in the pumped well and each observation well. Record measurements are taken as part of the test on an aquifer constant-rate test field data sheet (Appendix B). Record water levels before the start of the test.Then record levels during the pumping period at an interval of 5 to 10 minutes (depending on the drawdown rate and using professional judgment). Finally, record levels after the pump have stopped until the test well's water level is within 10 percent of its initial (pre-pumping)water level. Ahtna Environmental,Inc. 14