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level in this well had not yet stabilized. However, the level had not declined after another half hour <br /> had elapsed. All wells were then purged of standing water. Nine to 1.2 gallons of water were <br /> pumped from each well (except the two small-diameter piezometers fKF-6 and KF-7]). The purge <br /> water was stored in 55-gallon drums on site. After purging, the depth to the static water level in KF- <br /> 5 was re-measured, and even though the water depth remained stable,the reading was recorded. <br /> After purging, water samples were collected with a disposable plastic bailer and placed in 40-m1 <br /> vials. A 1-liter bottle sample was also collected for total lead analysis. The bottles were labeled and <br /> logged and placed in a cooled ice chest for later transport to Sequoia Analytical Laboratory. The <br /> laboratory report and chain of custody form are in Appendix B. <br /> 4.0 RESULTS <br /> 4.1 Depth to Groundwater and Hydraulic Gradient <br /> The static water level fell by approximately 18 inches in all wells except KF-5, where the level <br /> dropped by only 6 inches. The depth to groundwater now averages over 9 feet, which is about one- <br /> and-one-half feet deeper than last year at this time. <br /> The data in Table 1, along with data supplied by Gettler-Ryan,were used to contour the piezometric <br /> surface and interpret the groundwater flow direction, which are illustrated in Figure 3. Beneath <br /> Kwikee Foods, the piezometric surface slopes eastward, which is the normal groundwater flow <br /> direction. Beneath the Chevron site, the piezometric surface slopes toward the center of that site, <br /> where a closed depression surrounding MW-1, MW-2, MW-3, and MW-8 developed during the <br /> first quarter of 2002 and is still present. Between the two sites,just west of monitoring well MW-6, <br /> there is a slight crest or divide in the piezometric surface, separating eastward and westward flow. <br /> In the First Quarter 2002 Report, we interpreted the depression beneath the Chevron site as the <br /> result of groundwater remediation at that site. Contouring suggested that the water table had been <br /> drawn down several inches by groundwater pumping. During the second quarter, however, remedial <br /> activities were suspended at the Chevron site and the piezometric surface began to recover. Beneath <br /> the Kwikee Foods site, the recovery was sufficient to restore the local groundwater flow direction <br /> (eastward). Beneath the Chevron site, the water level has not fully recovered and flow is still radial <br /> toward the extraction well(s). <br /> 4.2 Analytical Results <br /> The water samples were analyzed for Total Petroleum Hydrocarbons as gasoline and for volatile <br /> aromatic hydrocarbons (benzene, toluene, ethylbenzene, and xylene) using EPA methods 8015 and <br /> 8020. In addition, PHS/EHD requested that the samples also be analyzed for all gasoline <br /> oxygenates, 1,2-DCA, and EDB and for total lead. EPA methods 8260 and 7010 were used to <br /> analyze for these constituents. The results are shown in Table 2. <br /> • 4 <br />