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• Additional Investigation to Define the Extent of Groundwater Contamination Quik Stop Market No 121 Page 5 The static depth-to-water prior to pumping was 22 34 fbg, within the clayey sand, therefore, aquifer conditions at the time of the test were unconfined, with an initial top of aquifer at 22 34 fbg and an initial thickness of 18 5 feet RW-1 partially penetrates the aquifer to a total depth of 27 5 fbg The test was performed by installing an electric submersible pump into well RW-1 A Hermit2000 data logger equipped with three pressure transducers to measure drawdown, were placed in the pumping well and two nearby observation wells (MW-3 and MW-4) Manual water level measurements were periodically recorded in four additional observation wells The flow rate was measured and adjusted with a flow meter and checked periodically with a 5-gallon bucket and stop watch All recovered groundwater was discharged to an onsite storage tank, located on the southwest side of the property On July 26, 2001, depth-to-water measurements were collected in all onsite wells prior to the start of the test The water level in the pumping well was measured at 22 34 feet below the top of the casing with an available hydrostatic head of 5 32 feet Due to the low water table, CCI decided to run test at 1 gallon per minute(gpm) The constant-rate pump test was started at 8 55 a in At 11 55 a m , the well dewatered The well was allowed to recover, and a second test began at 12 35 p in . The second test continued for 20 hours at a sustained pumping rate of approximately 1 gallon per minute Once again, the Hermit 2000 data logger and pressure transducers were used to measure water levels in the pumping well (RW-1) and the two observation wells (MW-3 and MW-4) Manual water level measurements were periodically measured in observation wells(MW-2, MW-5) CCI was unable to measure the water levels in monitoring well MW-7 due to a parked car At 8 30 a in on July 27, 2001, the pumping test was discontinued The pump was turned off and a recovery test was started The Hermit 2000 data logger and pressure transducers were used to measure the recovery in the pumping well and the two observation wells (MW-3 and MW-4) Manual water level measurements were recorded in MW-2, MW-5 and MW-7 (after the parked car was moved) The recovery test was discontinued after one hour, at which time the water level in RW-1 had recovered 1 576 feet or to within 98 % of its initial level Pumping and Recovery Test Analysis RW-1 was pumped for 20 hours at an average rate of I gpm Drawdown data were recorded at RW- 1, MW-3 and MW-4 The water level dropped 0 83 feet after 60 minutes and then continued to rise during the remainder of the test The water level in MW-4 also rose a total of 0 23 feet above the initial water level The drawdown data measured manually in the outer wells (MW-2, MW-5 and MW-7) indicated the water levels either rose or did not decline enough for the data to be used for pump test analysis No barometer data was available to correct for atmospheric pressure changes during the test Therefore,only the data from RW-1 were analyzed for both pumping and recovery conditions The field data sheets and Aqtesolv software results are provided in Appendix C