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Date: December 20,2002 <br /> Quarter: 3rd Quarter,2002 <br /> DISCUSSION: <br /> Total petroleum hydrocarbons as gasoline (TPHg), benzene, toluene, and total xylenes were reported in wells <br /> sampled this quarter at concentrations that are generally consistent with previous quarterly monitoring events. Fuel <br /> oxygenates including methyl tent-butyl ether (MtBE), tertiary-butyl alcohol (TBA), and 1,2-dichloroethane (1,2- <br /> DCA) were also detected in groundwater samples collected this quarter at concentrations consistent with historical <br /> data. Other fuel oxygenates analyzed were reported as below laboratory reporting limits. Groundwater elevations <br /> decreased during the quarter. Groundwater flow direction and gradient were consistent with previous quarters. <br /> Three site visits were conducted to optimize and maintain the SVEIAS system. Approximately 99 lbs of TPHG were <br /> removed during the third quarter 2002,with a cumulative mass of 1,645 lbs since startup(09128100). The AS system <br /> was not operational until August 27,2002 due to a broken compressor. The SVE system was in compliance with the <br /> San Joaquin Valley Unified Air Pollution Control District permit to operate. <br /> This report is based on data, site conditions,and other information that are generally applicable as of the date of the <br /> report,and the conclusions and recommendations herein are therefore applicable only to that time frame. <br /> Background information, including but not limited to previous field measurements,analytical results, site plans,and <br /> other data has been furnished to URS by Atlantic Richfield Company, its previous consultants, and/or third parties <br /> that URS has used in preparing this report. URS has relied on this information as furnished. URS is not responsible <br /> for nor has it confirmed the accuracy of this information. <br /> Field measurements have been supplied by a groundwater sampling subcontractor. URS has not performed an <br /> independent review of the field sampling data and is neither responsible for nor has confirmed the accuracy of these <br /> • data. <br /> TABLES <br /> Table 1 Groundwater Elevation and Analytical Data <br /> Table 2 Fuel Oxygenates Analytical Data <br /> Table 3 Floating Product Monitoring Summary Well VW-51) <br /> Table 4 Operational Uptime Information of the Soil Vapor Extraction System <br /> Table 5 Flow Rates and Analytical Results of Air Sample Analyses <br /> Table 6 Extraction and Emission Rates <br /> FIGURES <br /> Figure 1 Groundwater Elevation Contours <br /> Figure 2 Groundwater Analytical Summary <br /> Figure 3 Influent Concentrations vs.Time <br /> Figure 4 Cumulative Mass Removed vs.Time <br /> APPENDICES <br /> Appendix A Field and Laboratory Procedures <br /> Appendix B Laboratory Analytical Reports,Chain-of-Custody Documentation,and Field Data Sheets <br /> • <br /> K:V5 BP ARC010054813-QTR 02\548 GIAMR3QDldc Page 2 <br />