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Date July 14,2004 <br /> Quarter 2nd Quarter,2004 <br /> DISCUSSION: <br /> Gasoline range organics (GRO), benzene, toluene, ethylbenzene, total xylenes (BTEX), methyl tert-butyl ether <br /> (MtBE), and tert-butyl alcohol (TBA)were reported above method detection limits in groundwater samples collected <br /> from site wells during this quarter MtBE and TBA were reported as below method detection limits in MW-2 this <br /> quarter In MW-4, GRO concentrations decreased and TBA was reported as below method detection limits TBA <br /> was reported above method detection limits in MW-5 for the first time since analysis for TBA began in July 2003 In <br /> MW-6, GRO concentrations increased, low-level concentrations of toluene and MtBE were detected above method <br /> detection limits, and ethylbenzene concentrations decreased relative to the previous quarter MtBE decreased and <br /> TBA was reported as below method detection limits in MW-7 GRO was reported above method detection limits in <br /> MW-8 for the first time since July 2001 In AMW-5, MtBE was reported at the lowest level historically and TBA <br /> was reported as below method detection limits this quarter Total xylenes were reported above method detection <br /> limits in AMW-6 for the first time since July 2001 Otherwise, reported concentrations were generally consistent <br /> with historical data <br /> Groundwater elevations in the site monitoring wells generally decreased relative to the previous monitoring event <br /> The inferred direction of groundwater flow across the site was to the northwest at an average hydraulic gradient of <br /> 0 005 feet/foot (ft/ft) Regionally, the inferred direction of groundwater flow was toward the northwest at an average <br /> hydraulic gradient that ranged from 0 005 to 0 011 ft/ft A regional groundwater elevation contour map (Figure 1) <br /> and a regional groundwater analytical summary (Figure 2) were created with data from the former Chevron service <br /> station at 575 Grant Line Road and the former Scotty's service station at 574 Grant Line Road <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 /> • TABLES <br /> Table I Groundwater Monitoring and Analytical Data <br /> Table 2 Fuel Oxygenates Analytical Data <br /> Table 3 Groundwater Gradient Data <br /> FIGURES <br /> Figure 1 Regional Groundwater Elevation Contours <br /> Figure 2 Regional Groundwater Analytical Summary <br /> Figure 3 Concentration and Water Level Trends(Well MW-2) <br /> APPENDICES <br /> Appendix A Sampling and Analysis Procedures <br /> Appendix B Laboratory Analytical Reports,Chain-of-Custody Documentation,and Field Data Sheets <br /> Appendix C Former Chevron and Former Scotty's Groundwater Monitoring Data <br /> Appendix D GeoTracker Upload Confirmation <br /> K 1Wpro essU5 BP ARC011 11945Qua ulyl2 QTR 64111194 GWMR 2Q64 doe Page 2 <br />