SITE INFORMATION AND CORRESPONDENCE

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Caoepa's Car Wash SVE Start-up Report November 30, 2004 Page 3 of 460,000 ppbv indicates that correction factor of 2.8 should be used for higher concentrations. The effluent PID measurement of 1 .0 ppm compared to the laboratory measurement of 3 ,000 ppbv indicates that correction factor of 3 should be used for lower concentrations, FLOW MEASUREMENTS AND CALCULATIONS Direct measurement utilizing a pitot tube was used to calculate the influent airflow rate at two points on the vapor stream. These measurements confirmed the reading from a dedicated pitot tube that is displayed on the equipment controls and is continuously recorded to a digital format. The pitot tube was placed in a straight segment of the inlet pipe, between the SVE well manifold and the SVE unit, and between the air stripper and the SVE unit. The calculation considered the pitot tube reading (from a manometer), in-line air temperature, ambient air pressure, and a correction factor (provided by the manufacturer) for humidity and inline pitot tube placement, The direct measurement for the soil vapor well influent of 038 inches of water through a 3 -inch diameter pipe indicates that the rate of flow, Qal (Qsoil), was 120 cubic feet per minute. The direct measurement for the , soil vapor well influent of 0. 10 inches of water through a 4-inch diameter pipe indicates that the rate of flow, Qa2 Qstripper), was 110 cubic feet per minute. These calculations are detailed in an attached document. The digital readout, Qtotal, indicated that the SVE system is averaging approximately 240 cubic feet per minute (CFM) . The sum of Qsoil and Qstripper were in close agreement with the dedicated pitot tube and digital readout that will be used for future monitoring of the equipment. EFFLUENT MASS CALCULATION The effluent flow rate for the SVE system was estimated by direct measurement of the influent, A calculation for influent rate of the fuel (natural gas) indicates that its contribution to the total effluent is negligible. The total estimated effluent for the SVE system, therefore, is 240 CFM. Laboratory analysis of the effluent sample detected TPH at a concentration of 3000 ppbv, and also reported TPH in a mass .per volume concentration of 12000 micrograms per cubic meter (µg/m'). Based upon an effluent flow rate of 240 CFM it is calculated that a total of 0 ,258 lbs./day of hydrocarbon constituents are being released to the atmosphere. ( 12000 µg/m') x ( 1 lbs/4.536 x, 108 µg) x (240 ft'/min.) x (m'/35 ,31 ft ) x ( 1440 min./day) _ 0 .258 lbs/day This quanity is less than the maximum VOC emission rate of 2 pounds per day. [District Rule 2201 ] Laboratory analysis of the influent sample indicated that TPH was detected at a concentration of 480,000 ppbv. Based upon an influent flow rate of 240 CFM it is calculated that an estimated of 10 lbs./day of hydrocarbon constituents are being treated per day. (480000 gg/m') x ( 1 Ibs/4.536 x 108 µg) x (240 ft /min.) x (m3/3531 ft ) x ( 1440 min./day) _ 10.357 lbs/day A weekly field log is being maintained on site and will include influent and effluent hydrocarbon concentrations measured with a PID, rate of flow, running time, combustion chamber exhaust temperatures, and various other parameters . [District Rule 1081 , 2201 ] If the system is shown to exceed the Authority to Construct limits during the monitoring, the system will be shut down and the SJVAPCD will be notified. An Installation and Efficiency Report will be prepared and submitted along with the R P■ ,a CONDOR