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1 SVE system Installation and Efficiency Report Canepa s Car wash(Pacific Avenue) June 25 1999 ' Page -3 5 0 SOIL VAPOR EXTRACTION SYSTEM INSTALLATION 51 PIPING AND MANIFOLDS ' The layout of the piping and manifold system is shown in Figure 4, Appendix A The piping connecting soil vapor extraction wells SV-1 through SV-9 consists of four-inch diameter PVC and was installed as ' part of a previous SVE system that operated at the site from 1994 to the Fall of 1996 The current SVE system has been provided by the Fund and was manufactured by Burners and Controls 1 his system was previously located at 825 East Main street in Turlock, California and operated under STVZTAPCD, ATC ' 4N-3297-1-0 The piping from the extraction wells was manifolded to the SVE unit Each extraction well is equipped with a valve at the manifold to open or close the vapor conduit to the SVE unit I 5 2 THERMAL OXIDATION UNIT The SVE thermal oxidation unit was installed approximately 70 feet south of SVE well array and enclosed by a chain link fence with a lockable gate A supplemental fuel (natural gas) source was connected to the thermal oxidation unit via an underground gas conduit installed and connected by PG&E A i epresentative of PG&E also installed a gas meter for the thermal oxidation unit An electrical power source was provided by means of a temporary drop to a pole located adjacent to the SVE ' enclosure A representative from the City of Stockton inspected the installation of the gas and electrical connections during the installations The SVE system is intended to operate 24 hours per day, 7 days a week The thennal oxidation unit includes a water vapor knockout drum, a dilution air valve, a blower, a flame arrestor, a thermal combustion chamber, and exhaust stack The safety shutoff apparatus for the system includes a flame I out ultraviolet sensor, a high temperature switch for the combustion chamber, a high and low gas pressure switch, a low air flow switch, a cooling blower shutdown switch, LEL shutdown switc,ll, an effluent knockout drum high water level sensor, and a discharge drum full tank sensor The discharged effluent is stored in 55-gallon drums for periodic removed as necessary 6 0 EFFICIENCY OF THE SOIL VAPOR EXTRACTION SYSTEM The efficiency of tine soil vapor extraction system is dependent upon its ability to extract VOCs from the subsurface, destroy the VOCs by then-nal oxidation, and produce a vacuum in the subsurface to influence the soil contamination plume The following sections describe the analytical testing, field monitoring Iand system analysis for evaluating the efficiency of the soil vapor extraction system 6 1 SYSTEM START UP On March 9, 1999, an initial inspection was conducted to initiate operation of the SVE system However, a VOC destruction efficiency of 95% was not demonstrated and consequently, the start up of the SVE systern was aborted A second inspection was conducted on March 15, 1999 lir samples were obtained from both the inlet (influent) and exhaust (effluent) for evaluation of the efficiency of the SVE system In addition vapor concentrations from the influent and effluent were measured concurrently with a photoionization detector (PID) to calibrate the PID for future field measutenients The, influent air sample collected for laboratory analysis was collected directly frim a port lmated between the vacuum pump and the burner The sample was collected by filling a Fcdlarfl bag directly from the sampling port The effluent air sample coilc.ctcd for laboratory analysis was collected by drawing air from the exhaust, though a stainless steel tube, using the vacuum purnp of the PID, into a Tedlar© bag ne sample containers were labeled, placed in a cooler chilled with ice, and delivered, in accordance �� CONDOR