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Workplan for Interim Remediation&4`h Quarter 2000 Groundwater Monitoring Report Former Moore Petroleum Bulk Plant,5491 F Street,Banta,California Page 5 of 9 Wellhead connections will be completed approximately 18 inches below surface grade by adding a FVC tee connection to the existing and proposed well casings. The two vapor wells (VEW-1 and VEW-2) will have a four-inch PVC conduit running from the proposed compound to the wellhead and connected to the well casing with a four-inch FVC tee. Four-inch PVC pipe will be connected to the well casing at the tee location and routed to the remediation compound. This procedure will be repeated for all three groundwater recovery wells (RW-1, RW-2 and RW-3).. Surface completion for each well head will be made with a new traffic rated well box, set in a 12- inch concrete collar and sealed during resurfacing (Figure 4). PROPOSED PUMPING TEST DETAILS Apex proposes to install a submersible groundwater pump inside remediation well RW-2 (Figure 4). RW-2 was selected as the pumping location based on the proximity to the former source area and this well is between RW-1 and RW-3. Apex proposes to monitor groundwater elevations at four locations during the pumping test. Apex will install pressure transducers in three groundwater monitoring wells (MW-3, MW-8, and MW-9) and one recovery well (RW-1)to determine changes in water levels during the test (Figure 2). Additional water levels will be collected manually with a water level indictor at other monitoring well and recovery well locations throughout the test. This additional water level information will be recorded in a field notebook. Apex proposes to conduct a pre-test pumping test to verify the hydraulic properties of the aquifer. Apex will begin pumping groundwater from RW-2 at a rate of approximately 10-gallons per minute (gpm). If field observations warrant, the pumping rate may have to be adjusted and the test restarted (after allowing time for the aquifer to recharge within 95 percent of original water levels). All evacuated water will run through a flow totalizer meter to record total flow and calculate flow rates during the test. Apex anticipates conducting a 48-hour pumping test after the pre-test. Apex will synchronize all the data loggers and begin collecting data for approximately 15-minutes prior to restarting the PUMP. Based on 48-hours of pumping time, the test will produce approximately 28,800 gallons of water that will require proper disposal. Two water tank trucks, each with a capacity of 21,000 gallons will be on-site to contain the water. Apex personnel will collect groundwater samples during the test in accordance with SOPS included as Appendix B. The groundwater samples will be analyzed by a state certified laboratory for TPHg and TPHd by modified EPA Method 8015; BTEX by EPA Method 8020; the `five oxygenates' and 1,2 DCA by EPA Method 8260; and iron and calcium (to determine the possibility of fouling the groundwater treatment system).