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CLEARWATER G R O U P Environmental Services foot layer of hydrated bentonite Time release coated bentorute pellets will be used to drop through the standing water anticipated to be in the annular space The remaining annular space will be filled with cement and a tamper-resistant box will be concreted in place over the wellhead The test point/well will be developed by surging and bailing following installation Development will involve the removal of water from each well until such time that it is relatively free of sediment, and pH, temperature, and conductivity parameters have stabilized It is anticipated this will not exceed ten saturated casing volumes Soil cuttings and auger/sampler rinseate will be stored on-site in labeled 55-gallons drums pending future removal and disposal The proposed borehole location for the air sparge test point is shown in Figure 1 Tentative construction details for the sparge test point are attached It is anticipated that this well will be used as an active sparge well during full-scale remedial system operation if this technology proves effective in remediation of this site Step-drawdown groundwater extraction test Clearwater will conduct a brief step-drawdown test on the new dual-phase test well, which will allow for a rough determination of sustainable flowrates, and specific capacity for the well Groundwater extraction for this site is primarily considered for dewatering a portion of the saturated zone in order to expose more contaminated soil for vapor extraction, thus longer term pumping tests used to determine hydrogeologic parameters and actual capture zone are not being tested at this time The test will be conducted in steps by pumping water from the well at increasing flow rates and monitoring the depth to water in the pumping well using an electric water sensor Prior to initiating each test, an electric pump will be placed in the well so that it is approximately two feet off the bottom of the well, and the static water level in the pumping well will be measured The pump will be started at a low flow rate (i a approximately I gpm) and the water level will be periodically gauged Each step will proceed for approximately one-half to one hour or until water level in the well has stabilized The flow rate will then be adjusted upward to complete several additional steps, based on initial field data, until a flowrate is achieved which nearly dewaters the well It is anticipated that this well will be tested for 3 to 4 hours Water pumped from the well will be stored at the site pending appropriate disposal upon receipt of characterization samples Z&I78C Workplan for remedial feasibility testing 8 Angnst 200I