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Evaluation of Aquifer Parameters Purpose and Scope RESNA Industries conducted a series of constant-rate pumping tests at the site to evaluate hydrologic and well conditions and provide baseline information for the possible design and operation of a ground-water remedial system The testing program comprised three separate elements designed to provide different types of information. The first element of the test program consisted of two short-term constant-rate tests using well RW-1 These tests provided information regarding the well productivity and efficiency and were used to select the rate for the longer-term constant-rate pumping test which constituted the second element of the testing program The long-duration, constant-rate pumping test utilized well RW-1 for production and piezometer PZ-1 and wells MW-1 and MW-3 as observation points. Data from this test were used to evaluate the aquifer hydraulic parameters transmissivity M and specific yield (S,,) and to provide information regarding boundary conditions and anisotropy The third component of the test consisted of a penod of static ground-water monitoring These data were used to establish non-pumping conditions and to aid the evaluation of the significance of water-level changes observed during the later pumping test. . Test Instrumentation and Format The production well RW-1 was outfitted with a 4-inch submersible pump which was plumbed through a gate valve and flow meter to a 26,000-gallon storage tank onsite The discharge rate was controlled and recorded manually Drawdown in the pumping well and in observation points PZ-1, MW-1 and MW-3 was recorded both manually with a conductivity probe and automatically using a data logger/pressure transducer system. The first phase of the test program began with two short-duration constant-rate tests of approximately 0 5 and 2 0 gallons per minute (gpm) The pumping duration of each test was approximately 60 minutes The well was allowed to recover completely between each test Water level drawdown at 60 minutes elapsed pumping time for both short term tests and the 24 hour test was used to calculate well productivity in gpm per foot of drawdown (gpm/ft) The reciprocal of productivity, specific drawdown (ft/gpm), is plotted versus the pumping rate for the three tests on Plate 1 This plot is discussed in further detail in the following sections The Iong-term test entailed pumping well RW-1 for 1440 minutes (24 hours) at 2 5 gpm while monitoring drawdown in piezometer PZ-1 and wells MW-1 and MW-3 At the end of the pumping period, the complete recovery of well RW-1 was monitored During the final portion of the test program, static water levels in well RW-1 were monitored