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In May 2003, SECOR, Inc. submitted a report on the fonner Chevron station, entitled C_oneeplual Site 1Lrodel. That report attempted to show that a plume of contaminated groundwater originating at the Kwikee Foods site has co-mingled with a plume of contaminated groundwater that originated at the Chevron site. EHD recently reviewed both site models and subsequently infonned Upgradient Environmental by telephone that 1;111) favors the Upgradient interpretation at the present time and is considering the request for site closure. EHD has also contacted the Regional Water Quality Control Board to discuss closure, and was instructed by the Water Board to require additional information regarding the presence or absence of the hydrocarbon 1,2-dicHoroetliane (1,2-DCA) before granting site closure. 3.0 MONITORING PROCEDURES Groundwater monitoring took place on August 21, 2003. Gettler-Ryan Inc. monitored the neighboring Chevron site on the same date and provided water-depth measurements and laboratory data. After the wells were opened and allowed to equalize with atmospheric pressure, the depth to groundwater was measured with a water level meter and recorded on the Well Monitor Report (Appendix A). A battery-operated purge pump was then used to purge the wells of standing water. Six to 8 gallons of water were purged from the four wells that were to be sampled (KF-1, 2, 3, and 5). The purged water was stored in a 55-gallon drum on site. After purging, water samples were collected with a disposable plastic bailer and placed in 40-m1 vials. The bottles were labeled and logged and placed in a cooled ice chest for later transport to Sequoia Analytical Laboratory. The laboratory report and chain of custody form are in Appendix B. 4.0 RESULTS 4.1 Depth to Groundwater and Hydraulic Gradient The static water level at both Kwikee Foods and the former Chevron site was more than 2 feet lower on August 21 than on May 22 (Table 1). The amount of the decline increases eastward from the western side of the Chevron site to the eastern side of the Kwikee site. For example, the elevation of the water table declined 2.27 ft (from —7.41 ft to —9.68 ft) in Chevron MW-3, 2.32 ft (from —7.07 ft to —9.39 ft in Chevron MW-1, and 2.40 ft (from -7.37 ft to—9.77 ft) in Kwikee KF-7. This has resulted in a strong reversal in the groundwater flow direction, as illustrated in Figure 3. When the sites were monitored in May, shortly after groundwater remediation ceased at the Chevron site, the cone of depression around the remediation wells had largely disappeared. A number of slight north-trending ridges and troughs were evident in the elevation contours, suggesting a disequilibrium condition during readjustment of the hydraulic gradient (see Second 3