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,t Mr. Jeffrey Wong <br /> June 24, 2005 <br /> Page 2 of 3 <br /> limited data available from field purge logs for wells MW14B and MW13C to estimate the <br /> transmissivity and hydraulic conductivity of the aquifer. Using these estimated parameters, <br /> which were comparable to values given in the literature, the theoretical drawdown in MW13C at <br /> various facility well pumping rates were calculated. We have estimated that a pumping rate of <br /> approximately 20 gallons per minute (gpm) for a period of 48 hours should be sufficient to exert <br /> a measurable drawdown (— 0.20 feet) in well MW13C, assuming communication between the C <br /> Zone and deeper aquifer. However, there is some concern that pumping at this rate for this <br /> duration may draw dissolved contaminants to the deeper aquifer tapped by the PDW. <br /> Consequently, Ground Zero is proposing a limited pump test. Ground Zero proposes to pump <br /> from the PDW at a rate of 30 gpm for a period of 2 hours and record the response in nearby <br /> monitoring wells. <br /> Specific field procedures to conduct the pump test are presented below. <br /> Static Water Level Measurements <br /> Prior to initiating any pumping from the facility well, the static water levels will be measured in <br /> wells MW7, MW13C, and MW14B for a minimum of 48 hours to establish normal water level <br /> fluctuations in these wells. Static water levels will be collected using Solinst Leveloggers or <br /> equivalent. <br /> Pump Test <br /> The objective of the pump test is to pump at a rate substantially greater than the current use of the <br /> PDW to simulate increased use of the well and measure the response at various depths in the nearest <br /> monitoring wells. <br /> Groundwater will be pumped from the PDW for a period of 2 hours at an expected rate of <br /> approximately 30 gpm. <br /> Drawdown in the facility well and the .observation wells (MW7, MW13C, MW14B) will be <br /> measured according to the following schedule: <br /> Elapsed Time Since Interval Between Minutes Interval Between Minutes <br /> Start or Stop of Test PDW Observation Wells <br /> Minutes Minutes Minutes <br /> 0-15 1 2 <br /> 15-60 5 2 <br /> 60-120 10 5 <br /> Water levels would be monitored for at least 24-hours after pumping is stopped to monitor recovery <br /> in the PDW and the observation wells. <br /> G:IGROUNDZBITULEBURG\Reponslworkplan\W Ppumptest_rev2.doc <br />