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25 March 2009 AGE-NC Project No. 95-0121 Page 7 of 9 The DPE remediation system will consist of a 25-horsepower, oil-filled liquid ring pump to simultaneously extract free-phase petroleum, ground water and soil-vapor from the proposed extraction well network. The vacuum pump under standard temperature and pressure is capable of producing a maximum vacuum of 29-inches of Hg with a nominal capacity of 200 cfm. DPE will be accomplished by installing 1 -inch diameter PVC, high density/highpressure tubing with an attached angle-cut tipped "stinger" from the top of the wells to an anticipated depth of approximately one foot above the completion depth of each well (refer to Table 1 for individual completion details). The target interval from well EW- 1 is the upper portion of HU3 which is fine grained; the target for VW- is HU 1/HU2; while the target for AW- 1 is the lowest portion of HU2. An air-tight seal will be formed between the 1 -inch diameter PVC tube and the well heads of each well utilizing a well-head assembly. The stinger will allow the extraction of soil vapor within a depressed water table, caused by the rapid extraction of water from within the well screens. From the well-head, 14nch diameter PVC piping will route the extracted free-phase petroleum, hydrocarbon impacted ground water and soil-vapor via the trenched conveyance system to connect to the liquid containment vessel under vacuum. From the separating chamber, the water will be processed (via process pump) to a secondary storage tank where it will be pre-treated with a scale inhibitor solution. The intermediate (pre-treated) water will then be pumped directly through an air stripper, then through three 2,000-pound media vessels containing liquid phase granular activated carbon. Simultaneously soil-vapor will be processed through an electric-heated catalytic oxidizer for soil-vapor treatment. Additionally, vapor from the air stripper will be processed through the electric-heated catalytic oxidizer. Processed and treated ground water will be discharged under City of Stockton permit into the on-site sanitary sewer conveyance system to the City sanitary sewage conveyance system located on Navy Drive. The treated water, at an approximate rate of 10 gallons per minute, will enter the on-site sanitary sewage conveyance system at the southernmost terminal clean-out. Processed vapor will be destroyed by catalytic oxidation and the byproducts exhausted into the atmosphere under SJVAPCD Permit To Operate (PTO),which will be obtained following the SJVAPCD inspection at system start-up. A diagram of the planned system is illustrated in Figure 6. 4.3 . 1 . DPE-Soil Vapor Extraction Monitoring During the one-week start-up period for the DPE system, vapor samples will be collected and operational parameters will be monitored on a daily basis. Advanced GeoEnvironmental, Inc.