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Geosyntec c <br /> 5.2.2.2 Step-Drawdown Tests <br /> Four steps will be performed at each extraction well with a maximum duration of two hours for <br /> each step. The anticipated flow rates for the test are 50 gpm, 100 gpm, 150 gpm, and 200 gpm. <br /> These steps were selected based on the estimated range of flowrates that the extraction wells may <br /> be operated at. However, the flow rates and durations for the tests may be modified based on the <br /> measured depths to groundwater and observed hydraulic responses to pumping during well <br /> development. <br /> The step-drawdown tests will be started at the lowest flow rate (e.g., 50 gpm)and will be <br /> incrementally increased to conduct each step. Water levels will be measured in the extraction <br /> wells using both a pressure transducer and manual water level meter. Once the drawdown in the <br /> extraction well stabilizes, the flow rate will be increased to the next step. All changes in pumping <br /> rate and the times at which these changes occur will be recorded. <br /> The temporary piping at the well head will be configured with instantaneous and totalizer now <br /> meters and a sampling port. Equipment to be mobilized to the Site and used for the purposes of <br /> conducting the tests will include a temporary power source (generator), a valve to regulate the <br /> discharge, calibrated flow meters, and temporary piping and hose to transport the extracted water <br /> to water storage tanks. The time at which the pump is started and stopped for each step-test will <br /> be recorded. Totalizer and flow meter readings will be recorded on the field logs during the tests. <br /> In addition, manual water level measurements will be taken during the tests, including a water <br /> level measurement prior to starting the pump. <br /> 5.2.2.3 Data Analysis <br /> Data logged by the pressure transducers during the step-drawdown tests will be downloaded and <br /> evaluated to estimate the hydraulic properties of the aquifer, the specific capacity, and the well <br /> efficiency of EW-18A, EW-1813, and EW-19 for use in the GETS design modifications, <br /> including the pump selections for the new extraction wells. Transducer data will be processed <br /> using AgtesolvTM. The data analysis results will be included in the Extraction Well Installation <br /> Report. <br /> 5.2.2.4 Water Quality Sampling and Analysis <br /> At the end of the step-test, EW-18A, EW-1813, and EW-19 will be sampled to evaluate the <br /> groundwater chemistry for use in the GETS design modifications. <br /> Table 3 below, provides the analytical sampling plan for the proposed groundwater samples. <br /> Extraction Well Installation Work Plan 9 November 30,2018 <br />