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' associated piping, and remediation well network at the site Table 3 provides the well completion detail A more detailed description of each of the system components follows ' SVE System The new SVE equipment (i e , 300 standard cubic feet per minute (SCFM) thermal oxidizer) was ' installed at the site on April 7, 2005 The SVE was connected to the existing 500-gallon propane above ground storage tank (AST) for supplemental fuel supply, necessary hoses, pipes, gauges to transfer the propane, subsurface piping and wellhead connections between the SVE remediation wells, the AS ' remediation wells and the fenced remediation equipment compound There were originally four SVE remediation system wells (V W l through VW4) at the site VW 1 is ' screened between 10 and 30 feet bgs VW2 is screened between 20 and 35 feet bgs VW3 and VW4 were screened between 15 feet bgs and 25 feet bgs Each SVE wellhead connection includes a gate valve, vacuum gauge, sampling port, and flow rate measurement port ATC started the SVE system continuously on December 19, 2002 After the initial start-up operations for the original SVE system, VW3 was taken off line to reduce water ' production and VW4 was partially closed off but remains on line In July of 2004, the completions of VWl and VW2 were altered to further reduce produced water These wells now include stingers set at approximately 28 feet bgs and 32 feet bgs, respectively. ' MW 1 was converted to a vapor extraction well on February 10, 2004 The well completion of MW 1 was altered with a stinger, set at approximately 32 feet bgs Water Treatment System The SVE/AS system, groundwater treatment and discharge system (as previously configured) were started ' up on December 20, 2003 A water treatment system is required for the produced water associated with the SVE wells ' Components of the water treatment system include the knockout tank, located within the remediation compound, one 1,000-gallon drop tank, three transfer pumps, two 2,000 pound canisters connected in series containing aqueous-phase granular activated carbon (GAC), associated piping, control valves, pressure gauges, flow meters, instrumentation and controls From the effluent end of the lag canister, fluid is pumped into a 100-gallon tank where it is discharged to the sanitary sewer system located on the south side of the on site building ' During initial start up of the vapor extraction system, approximately 25 gallons of groundwater per hour were extracted from the four vapor wells (V W 1 —VW4) ATC closed the valves on V W l and VW2 and I only extracted from VW3 and VW4, which are screened approximately two feet above the current water level Seven gallons of groundwater per hour were extracted from VW3 and VW4 ' To operate the vapor extraction system more efficiently, ATC modified the vapor extraction system to include groundwater treatment and discharge to the City of Stockton sewer system (This is the groundwater that accumulates during operation of the vapor extraction side of the system ) ATC submitted the necessary permit application information for the discharge of treated groundwater and on ' November 6, 2002 the City of Stockton Department of Municipal Utilities (DMU) issued the Groundwater Discharge Permit (GDP) Following the issuing of the GDP, approximately 50 feet of 3- inch diameter, ABS pipe was placed on the surface of the site from the remediation compound to a S lenviro1625961quart1yl3gr-2005 doc 4 ATC ASSOCIATES INC 1