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A Grundfos®2-inch submersible pump was proposed for use. The proposed initial pumping rate was 0.5 gpm,with step wise increments of approximately 0.25 GPM until the maximum sustainable yield was achieved. That rate would then be used in the constant-rate test. The plan proposed processing the extracted water through three 55-gallon carbon canisters, collecting a treated sample for approval by the City of Stockton Sanitation District, and discharging into the City sewer system. After approval of the discharge permit,water extraction would resume and samples were to be collected at approximately 2-3,000-gallon intervals until termination of the test. 2.0 Step Test The Step test was performed May 13, 2009. The Grundfos®pump was lowered to a depth approximately 45 feet below the surface, or approximately 16 feet below the water table. Water was initially removed at a rate of approximately 0.75 gpm. Each hour,the rate was increased approximately 0.25 to 0.5 gpm. After nearly 6 hours, a stabilized rate of approximately 2.5 gpm was achieved. However, a lower rate of 1.25-1.5 gpm was selected for the subsequent constant-rate pumping test as a precautionary measure. After 332 gallons had been pumped into a 500-gallon storage tank, a baseline sample was collected. The test then resumed and an additional 148 gallons were pumped,bringing the total to 480 gallons in the 500-gallon storage tank(Table 1). A second water sample was then collected. The samples were transmitted to Excelchem Analytical. The first sample was analyzed for Total Petroleum Hydrocarbons in the gasoline range (TPH-g) and volatile aromatics (benzene, toluene, ethylbenzene, and xylene)by EPA method 8260B. The end-test sample was analyzed by EPA method 624 because that was required by the sewer discharge permit, and Trichloroethane (TCE) and Perchloroethane (PCE)were included in the analysis because chlorinated hydrocarbons had previously been detected in groundwater samples and the Sanitation District required verification of their concentration.. Lead analysis was performed by EPA 200.7. The laboratory report is in Appendix A, and the results are summarized in Table 2. The TPH-g concentration at the end of the test was about 18%higher than it was after the first 332 gallons had been pumped. Other concentrations were also generally higher, though by lesser amounts. Due to the detection of a total TCE/PCE concentration of 170µg/l (parts per billion), the Sanitation District rejected the request for continuous discharge of treated groundwater and required Valley Motors to submit a new application for batch discharge. A copy of this correspondence from the Sanitation District is in Appendix B. Because PCE was detected in the end-test sample, additional filtering was required to remove chlorinated hydrocarbons. A sample was collected after each filtering cycle and 2