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a ' P Cherry, 1979) 2.0 STEP TEST A step test was performed on extraction well EW-1 on July 13, 1994 The well was pumped at approximately one gallon per minute (GPM), the drawdown in the well stabilized in approximately eight minutes The controller box on the pump shorted out before any additional flow rates could be tested The step test performed by PES Engineering & Environmental Services (PES) indicated that the well tested was pumped at 0 9 GPM, 14 GPM, 2 1 GPM, and 3 1 GPM The graph of the data indicates that when the well was pumped at 2 1 GPM, the drawdown stabilized within an hour The graph of the data, further, indicated that when the well tested was pumped at 3 1 GPM, the drawdown stabilized within three hours Based on the drawdown observed during the aquifer test, described below, it appears that the extraction well could be pumped at 3 GPM or possibly higher rates without running the well dry 3.0 AQUIFER PUMP TEST Aquifer properties were determined based on a pumping test conducted at the site on July • 14 and 15, 1994 Groundwater was pumped from extraction x;ell EW-1 at a constant rate of 15 GPM for 1,440 minutes, 24 hours DrawdoAn was measured at monitoring wells MW-7, MW-8, and MW-14 using pressure transducers Maximum drawdown obtained in the extraction well dunng the test was 1 19 feet Ground-water elevations decreased in the observation weIIs Maximum drawdown observed was 0 670 feet in MW-7 A Grunfos two-inch diameter electncal pump was placed in ex-traction well EW-1 approximately one foot off the bottom of the well A 3,000 gallon storage tank was brought to the site to hold the water removed from the well dunng the test A Hermit 2000 data logger was used to record the drawdown data from the observation wells Pressure transducers were placed in wells MW-7, MW-8 and MW-14 The Site Plan (Figure 1) illustrates the locations of the observation wells with respect to the extraction well EW-1 The pump test was started at 1400 on July 14, 1994 and ran until 1400 on July 15, 1994 The depth to groundwater in EW-1, MW-7, MW-8, and MW-14 was monitored each hour The flow rate from the pump was monitored at the tank each hour The flow rate remained constant at approximately 15 GPM for the duration of the test The aquifer test data was downloaded from the Hermit 2000 data logger following the test The data was formatted for the AQTESOLV Model For each of the observation wells, MW-7, MW-8 and MW-14 the data was graphed and curve fitting was performed for the Theis method (Theis, 1935) and the Cooper-Jacobs method (Cooper and Jacobs, 1936) The AQTESOLV Model calculated a T and storativity (S)value for each of the observation weIIs O.."ay R.P.mg mm Oawow