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3.2 Groundwater Monitoring The depth to groundwater and the calculated elevation of the static water level since 1995 are shown in Table 1. Groundwater monitoring took place on twice during the quarter. On July 13, KF- I through KF-5 and Chevron's well MW-8 were surveyed, monitored, and sampled, and a groundwater gradient map was prepared (Figure 3). Wells KF-6 and KF-7 had not been drilled at that time. These wells were monitored and sampled on October 17. In order to prepare a valid gradient map, the depth to the static water level was re-measured in the other wells (except the Chevron well) at the same time (Figure 4). Except for the 1-inch diameter wells, a two-stage submersible pump was used to purge the wells. Water temperature and conductivity were measured during purging. The purged water is stored in 55-gallon drums on the east side of the property. Depth measurements and purging data are shown in Appendix C. After purging, water samples were collected with a disposable plastic bailer and poured into 40-m1 vials. The vials were labeled, logged, placed in a cooled ice chest, and transported to Sequoia Analytical for analysis. The laboratory report and chain of custody form are in Appendix D. 4.0 RESULTS 4.1 Depth to Groundwater and Groundwater Gradient The static water level has risen steadily since monitoring began at this site in earl 1995 g y and the depth to groundwater now averages about 7 feet. As a result of this rise, the soil-water interface is now within the upper clay bed (aquitard). The data in Table 1 were used to contour the piezometric surface and interpret the groundwater flow direction, which are illustrated in Figures 3 and 4. In July, the gradient arced from north-south to east-west beneath the site and sloped at 0.0008 ft/ft to the northeast. This is an exceptionally flat gradient, and combined with the high static water level the net effect would be very slow groundwater flow. The are in the gradient is even more dramatic in the October data, because the static water level in KF-6 and KF-7 is higher than expected. This forms a trough in the gradient. The trough trends northwestward in the southeastern quarter of the site, but then swings to the north beneath the building. Its origin is unknown. 4.2 Soil Samples The six soil samples from KF-4 and KF-5 were analyzed for Total Petroleum Hydrocarbons as gasoline, benzene, toluene, ethylbenzene, and xylene, and five gasoline oxygenates. The results are summarized in Table 2,which also includes the results of previous samples for comparison. 5