SITE INFORMATION AND CORRESPONDENCE

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i Quarterly Monitoring Report, April 2000 Canepa's Car Wash (Park Street) October 20, 2000 Page 2 3.1 GROUNDWATER MONITORING OBSERVATIONS AND PARAMETERS The static water level in each well was measured to the nearest 0.01 -foot with a battery-operated, flat tape, water-level meter. A clean, single-use, polypropylene, disposable bailer was lowered into each well to check for floating product, petroleum odors, and sheen. It should be noted that the groundwater table was above the top of the well screens. A slight petroleum hydrocarbon odor was noted in the groundwater sample collected from MW-2. A gray color was apparent in the groundwater samples collected from MW-2 and MW-4. The other groundwater samples were clear and had no color. Monitor wells MW-3 , MW-6, and MW-7 were purged using new, disposable bailers. MW- 1 , MW-2, MW-4,, and MW-5 were purged with a Redi-Flow submersible pump that was decontaminated prior to use. Approximately three well casing volumes of water were purged from each well (see the Groundwater Monitoring Field Forms in Appendix B) . The purged water from each well was placed in 55-gallon drums and left on site pending laboratory analytical results. 3.2 GROUNDWATER SAMPLING The groundwater samples obtained from monitor wells MW-3 , MW-6, and MW-7 were collected directly from disposable bailers by transferring the groundwater to two 40-milliliter glass vials . The groundwater samples from MW- 1 , MW-2, MW-4, and MW-5 were collected by filling two 40-milliliter glass vials with groundwater directly from the pump discharge tubing. The sample containers were labeled, placed in a cooler chilled with ice, and delivered in accordance with chain-of-custody procedures to GeoAnalytical Laboratories, Inc„ in Modesto, California for analyses. 4. GROUNDWATER MONITORING RESULTS 4.1 GROUNDWATER ELEVATION CONTOURS On July 12, 2000, the depth to groundwater was measured in each monitor well prior to the collection of groundwater samples. The average depth to groundwater on July 12, 2000, was approximately 22.5 feet below the well measuring points. The average depth to groundwater increased approximately 0. 1 feet since the previous monitoring event conducted in April 2000. The groundwater elevation ranged from 10 .48 to 12. 15 feet below mean sea level (bmsl). The groundwater elevation contour map (Figure 2, Appendix A) indicates a groundwater gradient generally toward the northeast. See Table 1 on the following page for groundwater elevation data. A hydrograph of groundwater elevations is included as Figure 6, Appendix A. Note from the hydrograph in Figure 6 and a comparison of the top of the well casing screen interval versus the depth to water in Table 1 that all wells are drowned, i.e. the water table is 17 to 23 feet above the top of the screen. i L ✓ CONDOR