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Revued OR Levine Fricke The lower well screens within the dual completion wells to be used for sponging or groundwater monitonng will be developed following the methodology identified below The grout around the deep well screens will be allowed to cure for a mmumun of 48 hours, after which the new wells will be developed by bailing, swabbing, or pumping This will remove any sediment left in the well during construction and enhance the hydraulic communication.between the well and surrounding sediments Observations concerning the quantity and clarity of water withdrawn will to recorded during this proem Indicator parameters (pH, temperature, and specific conductance) will be recorded during well development Approximately 3 to 10 well casing volumes will be removed from the well during the development process. In the event a well recovers slowly, the well will be pumped dry and then allowed to recover to approximately 80 percent of its static water level before being pumped dry again, or after approximately two bows This process will continue until the indicator parameters s%bd=e to within 10 percent of the prior measurement, or until 10 well volumes are removed. 9.2.5 Groundwater Sampling Groundwater sampling will be conducted during the different phases of the pilot test Before sampimg, a water level measurement will be made. Groundwater sampling will be conducted using eitlicr of the below discusser[ methods The first method is to purge approximately 3 well casing volumes of groundwater using either a bailer or a pump and measure indicator parameters After the indicator parameters have stabilized, a Teflon bailer will be used to collect groundwater from rite well The groundwater samples will be immediately decanted from the bailer into 1 laboratory-supplied 40-m1 volatile orgastic analysis vials with preservatives appropriate 1 for the analysis (see Table 1 of the Quality Assurance Project Plan, Appendix B of the Draft RI/FS Work Plan subnuttod April 24, 2002) The second metliod that may be utilized is a low flow or inirco purge system Using this methodology, sampling will be conducted using a low flow bladder pump_ To perform low flow groundwater sampling, the dedicated pump is carefully placed within the screened interval of the well. The primp is operated slowly to purge the water from the discharge tubuig and draw water from the aquifer formation through the screen immediately adjacent to the intake without mixing the stagnant water in the well The pumping water level is monitored to ensure that the drawdown in the well is kept to a minimutim. Dunng purging, groundwater is monitored for indicator parameters using a flow through cell. Purging continues until the monutored parameters stabilize, that is when (1) the pH is within 0 1 pH units, (2) EC is within 10 percent, and temperature is within 1.0 to 2.0 degrees Celsius. Samples will be collected after the temperature, pH, and EC have stabilized wpsvi:Cs.W,-,ev.0a123 dw-M Pagt 31 OV/TZ d BETO09b60ET 01 9060 25;9 OTS 3>io1ad 3N ozi 6=1-1 aj 00-9T 20, 60 -inr