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FP Recovered This Quarter: No Cumulative FP Recovered to Date: NA Approximate Depth to Groundwater: 44.81 to 46.89 feet below top of well casing Groundwater Flow Direction: South Groundwater Gradient: 0.002 ft/ft SVE SYSTEM QUARTERLY OPERATION AND PERFORMANCE Equipment Inventory: 2.3 HP Fuji Blower,two 3,000 Ib carbon vessels Operating Mode: Shut down pending installation of carbon system APCD Permit No.: N-4887-1-0(ATC) TPH Concentration End of Period(lab): --- Benzene Concentration End of Period(lab): --- MTBE Concentration End of Period(lab): --- Flow Rate End of Period: --- HC Destroyed this Period(lab): --- Cumulative HC Destroyed: 3467.25 lbs. Percent Time Operational: 0 DISCUSSION: iAt the time of the third quarter monitoring event, groundwater was encountered in the monitoring wells at depths ranging from approximately 44.81 to 46.89 feet below ground surface (bgs). Groundwater elevations in the monitoring wells decreased 2.87 to 3.27 feet since the second quarter 2003 sampling event. Depth to water measurements were normalized to mean sea level (MSL), and were used to construct a groundwater elevation contour map (Figure 2). The general groundwater flow direction on July 28, 2003, was calculated to be towards the south at an average gradient of 0.002 ft/ft. South-southeast groundwater flow direction has consistently been observed during previous monitoring events. TPHG (2,200 gg/L) and MTBE (11 µg/L) were reported in well MW-3. Benzene was not reported in any of the wells. No other fuel oxygenate compounds were reported in any of the wells. Analytical results from the July 28, 2003, sampling event are generally consistent with historical analytical data. TPHG, benzene, and MTBE data have been summarized on Figure 3. The SVE start-up was initiated on August 1, 2003, by conducting source testing in accordance with SJVUAPCD authority to construct requirements. The reported influent concentrations for TPHG, benzene, and MTBE in air sample collected on August 1, 2003, were 36,000 milligrams per cubic meter (mg/m3), less than 10 mg/m3, and 57 mg/m3, respectively. During the site visit on August 18, 2003, low destruction efficiency was observed for the SVE system and the system was shutdown after collecting effluent air samples. A TPHG break-through was observed in the effluent air sample at 100 mg/m3, and hence the system was not re-started pending carbon charge-out. =—� -Between October -16; 2003- and October 22; 2003,-Stratus-conducted-the ,carbon- change-out and - - - re-started the SVE system on October 22, 2003. The SVE system is currently being operated on a continuous basis. Tabulated analytical results with petroleum hydrocarbon mass removal and emission rates will be included in the fourth quarter 2003, monitoring report. • P:1USA Gasoline100651Qtrly120031USA_65_3QO3.DOC 57-KAWS