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1� :Z Date January 29,2004 Quarter 4`s Quarter,2003 • • The elevated reporting limits were the result dilutions performed by the laboratory in order to quantitate a target analyte(s) DISCUSSION: Total petroleum hydrocarbons as gasoline (TPHg), benzene, toluene, ethylbenzene, total xylenes (BTEX), methyl tert-butyl ether (MtBE), and tert-butyl alcohol (TBA) were reported above method detection lints in groundwater samples collected from site wells this quarter Analyte concentrations were generally consistent with historic data with the following exceptions TPHg concentrations increased in MW-6,VW-1,VW-2,VW-7,VW-11,and MS-2A but remains within historic ranges TPHg, toluene, and MtBE concentrations were reported as below method detection limits in well MW-5 this quarter In MW-6, a low level concentration of MtBE was detected for the first time since September of 1999 Low-level concentrations of benzene, ethylbenzene, and total xylenes were reported in VW-1 this quarter In VW-4, TPHg concentrations increased but remain within historic ranges, benzene, ethylbenzene, and total xylenes concentrations increased to historic levels, and toluene was reported above method detection limits for the first time since sampling began in December of 2002 In VW-8, TPHg, benzene, ethylbenzene, and total xylenes concentrations decreased to the lowest levels reported historically, and a low level concentration of MtBE was detected for only the second time since sampling began in May of 1997 In VW-10, TPHg concentrations increased but are consistent with historical data and BTEX concentrations increased but are estimated as discussed in the analytical data review Low-level concentrations of TPHg and BTEX were detected above method detection limits in MS-IA, MS-113, MS-2A, MS-2B, and MS-3A this quarter Though TPHg concentrations were generally within historic ranges in the MS wells sampled, BTEX concentrations generally increased to historic levels Methanol and 1,2-dichloroethane (1,2-DCA)were added to the analyte list this quarter Methanol was reported as below method detection limits in all groundwater samples collected from site wells this quarter 1,2-DCA was reported above method detection limits in the majority of groundwater samples collected from site wells this quarter with concentrations ranging from 0 89 to 160 micrograms per Liter(pg/L) Groundwater elevations generally decreased relative to the previous sampling event The inferred direction of groundwater flow across the site was toward the south to southeast with an average hydraulic gradient of 0 0006 to 0 0017 ft/ft This report is based on data, site conditions, and other information that are generally applicable as of the date of the report,and the conclusions and recommendations herein are therefore applicable only to that time frame TABLES Table I Groundwater Monitoring and Analytical Data Table 2 Fuel Oxygenates Analytical Data Table 3 Groundwater Gradient Data I FIGURES Figure 1 Groundwater Elevation Contours Figure 2 Groundwater Analytical Summary APPENDICES Appendix A Field and Laboratory Procedures Appendix B Laboratory Analytical Reports,Chain-of-Custody Documentation,and Field Data Sheets Appendix C GeoTracker Upload Confirmation K.1Wpruc WJ5 RP ARC01021301Quarterlp54 QTR 0312134)G WMR 4Q03 doc Page 2 i