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• <br /> recorder to record differences in hydraulic head to 0.01 foot <br /> accuracy on a continuous strip chart with recorded time. This will <br /> help establish a base line for the natural occurring fluctuations <br /> that may occur in the ground water elevation for this time period. <br /> During the first week of pumping, transducers will be placed in <br /> monitor wells MW2, MW3, MW4 , MW7 and MW8 . Data loggers will be <br /> used to continuously record and evaluate the ground water <br /> fluctuations derived during the pumping of monitor wells MW1 and <br /> MW3 at a combined pump rate of 2000 gallons/day (1 .4 <br /> ' gallons/minute) for seven days. The pumps will be down hole air <br /> jet pumps that air lift the ground water (causing down well <br /> stripping of VOCs ) from MW1 and MW3 to a sealed sediment <br /> collection tank that is vented to the incinerator. From the <br /> sediment trap the ground water will be sprayed into a 250 gallon <br /> capacity dump tank. This is were the first phase aerating will <br /> take place. The ground water will be heated and aerated by heated <br /> air jets within the dump tank for approximately 2 .5 hours. All <br /> VOC vapors produced from the aerating will be vacuumed off to be <br /> treated by the "Hartz" incenerator. Once the aeration has taken <br /> place the water (approximately 200-250 gallons ) will be dumped <br /> into the "ConVault" tank and aerated for another 2.5 hours prior <br /> to being pumped to a holding tank for sampling. Again the <br /> aeration in the "ConVault" is accomplished by heated air spray <br /> nozzles positioned in the botton of this tank. The treated water <br /> will then be pumped into the holding tank, a 15 ,000 gallon "Baker" <br /> tank, for testing during the initial one week start up. Once the <br /> City of Stockton Sewage treatment facility allows , the treated <br /> water will be pumped directly to the sewer for disposal , see <br /> Figure 7-Schematic of Pumping-Treatment of Ground Water. Prior to <br /> pumping, depth to ground water measurements will be obtained from <br /> all of the monitor wells . During the pump test these measurements <br /> will be continuously recorded by the data loggers for monitor <br /> wells MW2, MW3, MW4 and MW7 , and on an electronic strip chart <br /> recorder for MW8 . For the remaining monitor wells depth to water <br /> measurements will be obtained daily to 0.01' using a calibrated <br /> resistivity probe for the one week test period. Once pumping has <br /> ceased, the recovery rate (from reducing the pump rate to 1000 <br /> gallons per day) of monitor well MW3 along with MW2 , MW4, MW7 and <br /> MWS will be recorded using the recorded transducers as mentioned <br /> above. From this data, time drawdown curves will be plotted for <br /> each observation well and using time and distance draw down type <br /> curves for an unconfined aquifer, a calculated transmissivity and <br /> storage coefficient will be obtained. From this data a ground <br /> water modeling program will be used to determine the recovery rate <br /> and wells needed to capture the contaminant plume. <br /> 8 <br />