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Q ._ M <br /> � _ -�€ <br /> ^ Y. <br /> EA9 <br /> ^Kr <br /> tests were also used to select the rate for the longer term constant <br /> rate pumping test which constituted the third element of the testing <br /> program. <br /> The long-duration constant-rate pumping test utilized well MW5 for <br /> production and wells MWI, MV12, MW3, and MW4 as observation wails. <br /> Data from this test were used to evaluate the formation hydraulic <br /> parameters transmimnsivity (T) and specific yield (SY), and to provide <br /> information regarding aquifer boundary condiricns and anisotropy. <br /> This data is used in the evaluation of the recovery system capture <br /> zone. <br /> The production well (MW5) was outfitted with a 4" submersible pump <br /> which was plumbed through a gate valve and flow meter to a 2,000 <br /> gallon storage tank on site. The discharge rate was controlled and <br /> recorded manually. <br /> During the first portion of the test program static water levels in <br /> all the wells were monitored for approximately 2 hours. `:')lis <br /> - monitoring was conducted to evaluate short term fluctuations in the <br /> shallow aquifer under non-pumping conditions. There was a difference <br /> in both the magnitude and the trend of the water level changes in the <br /> wells. The range of fluctuation is approximately 0.01-0.02 foot of <br /> water, which probably represents a response to normal diurnal <br /> pressure changes. Generally these changes are small for unconfined <br /> aquifers. The differences between the two wells may be due to <br /> variations .in their barometric efficiencies. <br /> The second phase of the test program consisted of three short <br /> duration constant-rate tests of well MW5 at 2.0, 3.3., and 4.8 gallons <br /> per. minute (gpm). The pumping duration of each test was <br /> approximately 30 minutes; the well was allowed to recover completely <br /> between each test. The drawdown at 20 minutes elapsed pumping time <br /> for each test was used calculate well productivity (gpm/ft. ). The <br /> ... inverse of productivity (.ft/gpm) is plotted versus the pumping rate <br /> for the three short: -germ tests or, Figure 6. This plot is discussed <br /> in detail below. <br /> After the short-duration tests were completed the production well was <br /> allowed to recover before beginning the long-duration constant-rata <br /> test. The long term discharge rate of 2.0 cpm was selected based on <br /> extrapolation of the short tern.: test results. The test entailed <br /> p=ping from well WN5 for approximately 400 minutes while monitoring <br /> drawdown in wells MW1, MW2, rW3, and 'MW4. After 400 minutes elapsed <br /> pumping time the discharge rate was increased to 2.5 gpm and <br /> maintained for an adeitional 200 minutes. At the end of the pumping <br /> period the recovery of well MW5 was monitored. Semilog Flots of the <br /> drawdown versus time are shown on Figures 7-11. <br /> The short term constant rate tests showed significant decline in well <br /> - - -` - - -productivity (pumping rate/ft of-drawdown)-with-increasing-discharge ----- - -.--- ---- <br /> rate. The reciprocal of productivity (s/Q or drawdown/gpm) is <br /> plotted versus the pumping rate (gpm) for each of the three short <br /> term tests and the 2.0-2.5 gpm longer term test on Figure 6. <br /> Weber Point Property 6 _ <br /> H2ORAP791.TLP - - _ <br />