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Quarterky Monitoring and Sensitive Receptor Survey Report Canepa's Car Wash(Park Street) November 5,2001 Page 2 3.0 QUARTERLY GROUNDWATER MONITORING—OCTOBER 2001 On October 9, 2001, Condor representatives made field observations and collected groundwater samples from the seven monitor wells at the site (see Figure 2, Appendix A) The wells were sampled in the following order MW-1, MW-4, MW-2, MW-7, MW-5, MW-6, and MW-3 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 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 all the I well screens A strong petroleum hydrocarbon odor was noted in the groundwater inspection samples collected from MW-2 and MW-5 All of the other groundwater inspection samples were noted as not having petroleum hydrocarbon odor IAll monitor wells were purged using a clean, single-use, polypropylene, disposable bailer Approximately three well casing volumes of water were purged from each well The purged water from I each well was placed in 55-gallon drums and left on site pending laboratory analytical results The groundwater monitoring field forms and groundwater measurement field form are included in Appendix B 3 2 GROUNDWATER SAMPLING The groundwater samples from the monitor wells were collected by filling three 40-m1 glass vials with I groundwater directly from the bottom of the bailer using a 100-m1/minute bottom-emptying device The sample containers were labeled, placed in a cooler chilled with lee, and delivered in accordance with chain-of-custody procedures to Exelchem Environmental Laboratories, Inc , in Roseville, California for analyses 4.0 GROUNDWATER MONITORING RESULTS I4 1 GROUNDWATER ELEVATION CONTOURS On October 9, 2001, the depth to groundwater was measured in each monitor well prior to the collection I of groundwater samples The average depth to groundwater was approximately 25 2 feet below the well measuring points The average depth to groundwater increased approximately 12 feet since the previous monitoring event conducted in July 2001 The groundwater elevation ranged from 13 30 to 15 06 feet I below mean sea level (bmsl) The groundwater elevation contour map (Figure 2, Appendix A) indicates a groundwater gradient generally toward the northeast Groundwater elevation data is presented in Table 1, on the next page A hydrograph of groundwater elevations is included as Figure 3, Appendix A Note from the hydrograph in Figure 3 and a comparison of the tops of the well casing screen intervals versus the depth to water in Table 1, that the water table is approximately 14 5 to 19 5 feet above the top of the screen in all of the wells I i L CONDOR I