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3)revise the feasibility study to identify a more cost-effective method of remediation_ However, some months prior to receipt of that directive,Valley Motors began to experience financial difficulties that prevented payment for work that had been completed up to that time. Part of the difficulty was due to a slowdown in reimbursement from the State Underground Storage Tank Cleanup Fund. Due to the anticipated high cost of proceeding with remediation,all work at the site,including groundwater monitoring, was suspended until payments could be restarted and account balances could be paid off. During this period SJCEHD.has been very cooperative and understanding of the situation and not attempted for force Valley Motors into more severe financial difficulties. However,recognizing that.the site investigation has been stalled for more than.a year, SJCEHD notified Valley Motors in April 2011 that it is out of compliance with SJCEHD directives and ordered Valley Motors to submit a plan for groundwater remediation by May 31,2011.. 2.0 EXTRACTION WELL INSTALLATION As explained in the Groundwater Extraction Pilot Test.Report, the pumping test demonstrated that pumping from a 2-inch diameter monitor well is not.reliable. On numerous occasions;the pump failed and the system shut down,and an excessive number of site visits was required to the system. This drove up the cost and slowed the test. Therefore itwill be necessary to install two 4-in6.11 diameter extraction wells. The well (VM-9 and VM-10)will be constructed,of 4-inch diameter PVC and screened from 38 to 53 feet: The wells will be i:ristalled using a hollow-stem auger drilling rig and construction details are presented in Figure 3. Soil samples will be obtained at 5-foot intervals and screened using a PID. A,minimum,of two s for:laboratory analysis. Poring logs will be prepared and submitted. Drill cuttings will be stored:in drums on site. Upon completion, the drums will be transported to a disposal facility. 3.0:EXTRACTION SYSTEM CONFIGURATION Extracted water will be pumped to a.500-gallon holding tank.for temporary storage. A water meter will be plumbed ahead of the tank to measure the extraction rate and total volume extracted. The water will then be pumped through two 500-gallon granulated activated carbon vessels for treatment. Pumping through two vessels should solve the problem that was encountered during the 2010 pumping test,when four in-series 55- gallon carbon canisters were not sufficient in filtering chlorinated hydrocarbons and it was necessary to re-circulate the water through the canisters a second time.