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3.0 MONITORING PROCEDURES Groundwater monitoring took place on February 20, 2003. Gettler-Ryan Inc. monitored the neighboring Chevron site on the same date and provided water-depth measurements but rrot 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. Nine to 12 gallons of water were purged from each well (except the two small-diameter piezometers [KF-6 and KF-7]). The purge water was stored in 55-gallon drums on site. After purging, water samples were collected with a disposable plastic bailer and placed in 40-ml 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 rose by almost 3 feet during the first quarter at the Kwikee Foods site, and the depth to groundwater now averages less than 9 feet. A similar rise (nearly 4 feet) occurred during the first quarter of 2002, and the depth also averaged less than 9 feet at that time. This rapid rise is probably due to the abundant rainfall that took place in both late 2001 and late 2002. At the Chevron site to the west of Kwikee Foods, the water table remains depressed and is more than 9 feet below grade in some wells. The data in Table 1 and the data from Gettler-Ryan were used to contour the piezometric surface and interpret the groundwater flow direction, which are illustrated in Figure 3. As noted above, the water table is depressed in the eastern portion of the Chevron site, and is more than one feet deeper than in the wells at Kwikee Foods. The cone of depression at the Chevron site extends to the western side of the Kwikee site, but there is a slight ridge that trends northward from the center of the Kwikee site toward the Chevron wells in Elmwood Street. A similar "mound" has been observed occasionally in the past. As a result, groundwater flows westward toward the Chevron site from KF-1 and KF-3 but eastward or southward from all of the other Kwikee wells. These wells are presently beyond the influence of the Chevron remediation system. 4.2 Analytical Results The water samples were analyzed for Total Petroleum Hydrocarbons as gasoline using EPA method 8015, for volatile aromatic hydrocarbons (benzene, toluene, ethylbenzene, and xylene) using EPA 3 i