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After purging, water samples were collected with a disposable plastic bailer and placed in 40-m1 vials. The vials 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 Surveyed Well Elevations Well casing elevations provided by Morrow Surveying range from 0.9 to 1.63 feet above sea level and average 0.72 feet lower than those that were based on the previous survey (Table 1). This will result in a commensurate fall in the static water elevation in all wells and should be kept in mind when comparing the November water depth data to those from previous quarters. 4.2 Depth to Groundwater and Hydraulic Gradient The static water level fell by almost 1 foot (average of 0.92 feet) during the fourth quarter, and the depth to groundwater now averages more than 11 feet. This is a typical seasonal decline prior to the start of the rainy season. The data in Table 1 were used to contour the piezometric surface and interpret the groundwater flow direction, which are illustrated in Figure 3. The piezometric surface slopes westward toward the former Chevron site, and there is a closed depression surrounding the remediation wells at that site. Beneath Kwikee Foods,, the gradient is steeper on the east side of the property and there is a flat spot in the north-central part of the site, beneath the store. The westward gradient is rather unusual for the site; in the past,the gradient has sloped rather uniformly to the east or northeast. 4.3 Analytical Results The water samples were analyzed for Total Petroleum Hydrocarbons as gasoline and for volatile aromatic hydrocarbons (benzene, toluene, ethylbenzene, and xylene). The results are shown in Table 2. The samples from KF-3 and KF-5 were also analyzed for MTBE by EPA method 8020. Samples from KF-6 and KF-7 continue to be below detection limits for all analytes, and KF-5 joined that group this quarter. This is the first time that no hydrocarbons have been detected in KF- 5. Samples from KFA, 2, and 4 were also free of most hydrocarbons, although xylene was present in KFA and KF-4 and both xylene and toluene were detected in KF-2. Concentrations in all three wells were below I µg11 (ppb) and could easily be due to laboratory error or cross-contamination during sampling. These results should not be regarded as a reversal from previous trends. Concentrations in KF-3 rose from those that were reported in the third quarter, and were similar to those reported in August 1998, December 2000, and May 2001. The historical record of analytical results for two of the monitor wells is illustrated in Figures 4 and 5. Benzene and gasoline were both present at high concentrations from the time the investigation 4