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Step-Discharge Test Procedures The step-discharge tests were performed by pumping each well at increasingly higher discharge rates (steps) while monitoring the decreasing water level (drawdown) in the well and in nearby monitoring wells The step-discharge test for Well RW-IA was conducted on October 27, 1997 and the step- discharge test for Well MW-2 was conducted on October 28, 1997 Gregg Drilling and Testing provided the pumps and flow controls for the pump tests An electric submersible pump was used to pump water for the tests The ground water generated during the test was temporarily stored in a 6,500 gallon Baker tank The tank was emptied between tests by Phillips Services Inc Pressure transducers connected to a datalogger were used to monitor the water levels to the pumping well and in nearby monitoring wells during the test Manual water level measurements were also collected in all site monitoring wells during the test with an electronic water level indicator The step-discharge test for Well RW-lA consisted of 6 steps The first step was pumped at 1 gallon per minute (gpm) for 20 minutes, after which the flow rate was increased to 2 gpm for 20 minutes The third step was pumped at a rate of 4 gpm for 28 minutes, after which the flow rate was increased to 8 gpm for 120 minutes (2 hours) The fifth step was pumped at 12 gpm for 38 minutes and the final step was pumped at 16 gpm for 40 minutes The step-discharge test performed in Well MW-2 consisted of 2 steps The first step was pumped at 1 gpm for 60 minutes The second step was pumped at 2 gpm for 14 minutes, after which the well dewatered At the beginning of the step-discharge test in RW-1 A, a sample of the ground water was collected and preserved A second ground water sample was collected near the conclusion of the constant-discharge test in RW-IA The purpose of collecting these two samples was to determine if the concentration of petroleum hydrocarbons and MTBE in ground water would change after pumping for a period of time Step-Discharge Test Findings The purpose of the step-discharge test was to determine a flow rate that could be maintained for a longer duration constant-rate discharge test The data collected during the step-discharge test in Well RW-IA indicated that a pumping rate of 15 gpm would produce approximately 10 feet of drawdown and would likely be a sustainable pumping rate and not dewater the well during the constant-discharge test The step-discharge test performed in Well MW-2 indicated that the well could not support a pumping rate of 2 gpm without dewatering the well Pumping the well at 1 gpm during the step- 240-0783 7