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✓ '"►' Test Well Location and Design The proposed location of the test well is between monitoring well MW-6 and MW-1 about twenty feet southeast of MW-6 as close to the building as possible (see site map attached). The screen section of this extraction test well is proposed to cover from sixty to twenty-five feet below the surface. Due to the expected high flows of this test, a six inch PVC casing is proposed with an 0.02 slot screen. The proposed filter is #3 x #10 sand in a fifteen inch bore hole (see well construction drawing attached). Well development is proposed to include surging and purging to industry standards. Pump Test Procedure After purging,a submersible pump with a capacity of twenty-gallons per minute at one hundred feet of head will be installed. The proposed pump is a two horse-power submersible with a 1-1/2" discharge. Pump discharge is into a 21,000 gallon Baker tank. The proposed duration of the pump test is twenty-four hours or when the Baker tank is full,which ever comes first. The Baker tank shall have secure covers and be leak free. Soundings on the hour are proposed for monitoring wells MW-1,MW-1R,MW-2,MW-2R,MW-3, MW-3R,and MW-5. Soundings on four hour intervals are proposed for all other monitoring wells. Standards of the industry shall be applied to all sounding measurements.Pumping volumes shall be recorded on the hour. Proposed sampling of ground water discharge will be one set of samples at the start of pumping and one set at the end of pumping. Proposed laboratory analysis is by EPA Method SW802OF for BTEX and TPHg. All groundwater samples will be stored on ice and transported under chain of custody to a certified laboratory of analysis. Three methods are proposed for contaminated groundwater disposal. The method with the lowest cost to the owner will be chosen. 1. Method one is bioremediation of the discharge water while in the Baker tank. The water in the Baker tank will be held until discharge water samples reach non-detect for BTEX and TPHg. Bioremediated water will then be discharged under permit to the Stockton City sanitary sewer. 2. Method two is passing discharge water though a suitable activated carbon filter to remove all contaminates and discharging the filtered water in to the Stockton City sanitary sewer. 3. The third method is to transfer all discharges under manifest to a certified disposal unit. Report of findings The proposed report of findings shall include all monitoring well sounding data with a draw-down curve calculated for the last data set in the pump test. The "k" factor for the aquifer will be calculated off that draw-down curve for the pump test using Dupuit Theory Equation. The findings will also include the laboratory analysis results from the two groundwater samples extracted during the pump test. 3