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DISCUSSION Results of the third quarter 2000 groundwater-monitoring event indicate that the concentrations of dissolved hydrocarbons are generally consistent with concentrations detected in previous sampling events The highest levels of TPHG (137 pg/L) and benzene (2 18 ug/L) were detected in MW-5 and MW- 1, respectively The highest concentration of MTBE (Method 8260A) was detected at 161 Pg/L in MW-3 The direction of groundwater flow was east-northeast with a gradient of 0 0038 ft/ft This is consistent with previous groundwater monitoring events The groundwater elevation decreased approximately 2 5 feet in the monitoring wells from the previous sampling event (June 2000) Delta conducted a startup and source test of the AS/SVE system consisting of a KingBuch/Hass Tech Catalytic Oxider model MMC5a on September 28, 2000 The AS/SVE system is connected to vapor extraction wells VW-1, VW-2, VW-3, VW-4, VW-5D and VW-5S Soil vapors are being extracted from all vapor extraction wells The air sparge compressor is connected to sparge wells AS-1, AS-2 and AS-3 (see Figure 2) During systems startup, influent and fluent flow rates were recorded and samples collected The air samples were forwarded to a state-certified laboratory for analysis Analytical results are included in Appendix B and in Field Data sheets included in Appendix C The system is currently extracting approximately 60 cubic feet/minute (cfm) of soil vapors During startup the system is extracting approximately 14 45 and 0 05 lbs/day of TPHG and benzene The system is in compliance with the Authority to Construct issued by the San Joaquin Valley Unified Air pollution Control District (APCD) Ambient air is,being injected into the groundwater via sparge wells AS-1, AS-2 and AS-3 at the rate of 0 35 cfm and 10 psi pressure ATTACHMENTS • Table 1 Groundwater Monitoring Data • Table 2 Groundwater Analytical Results for Oxygenates • Figure 1 Site Location Map • Figure 2 Groundwater Elevation Contours (Third Quarter 2000) • Figure 3 Groundwater Analytical Summary (Third Quarter 2000) • Appendix A Sampling and Analysis Procedures • Appendix B Laboratory Analysis Reports and Chain-of-Custody Records • Appendix C Field Data Sheets i C WY Documentslarco105481QTRLY1200010548Q300 DOC Delta 11/14/00