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~ Y KEI-P89-1104 .R7 December 10, 1990 Page 8 The wells were developed on October 18, 1990. Prior to develop- ment, the wells were checked for depth to the water table using an electronic sounder, presence of free product (using paste tape) and sheen. No free product or sheen was noted in any of the wells. After recording the monitoring data, the wells were developed with a surface pump until the evacuated water was clear and free of suspended sediment. Monitoring and well development data are summarized in Table 1. The wells were sampled on October 26, 1990. Prior to sampling, monitoring data was collected and the wells were then purged of 15 gallons each. Water samples were collected using a clean Teflon bailer, which was rinsed with distilled water prior to sampling each well. The samples were decanted into clean glass VOA vials, sealed with Teflon-lined screw caps, and labeled and stored on ice until delivery to a certified laboratory. ANALYTICAL RESULTS Selected soil and all water samples were analyzed by Sequoia • Analytical Laboratory in Concord, California, for TPH as gasoline using EPA method 5030 in conjunction with modified 8015 and BTX&E using EPA method 8020. In addition, the samples from MW1 were analyzed for TPH as diesel using EPA methods 3550/3510 in con- junction with modified 8015, total oil and grease (TOG) using SM 503A&E and purgeable halocarbons using EPA method 8010. Analytical results of soil samples collected from the borings for monitoring wells MW1 through MW4 , indicate non-detectable levels of TPH as gasoline and benzene in all soil samples, except for sample MW3 at 30. 5 feet which showed 0. 088 ppm benzene. In MW1, TPH as diesel, TOG and EPA 8010 compounds were non-detectable in all samples, except for sample MW1 at 10 feet, which showed 76 ppm of TOG. Analytical results of the ground water samples collected from monitoring wells MW1, MW2 and MW4 indicate non-detectable levels of TPH as gasoline and BTX&E. In well MW3 , TPH as gasoline and benzene were detected at levels of 220 ppb and 7 . 6 ppb, respec- tively. In well MW1, TPH as diesel was detected at a level of 170 ppb, TOG was non-detectable and EPA method 8010 constituents were non-detectable, except for chlorobenzene and 1, 2-dichlorobenzene at concentrations of 2 . 3 ppb and 7 .4 ppb, respectively. Results of the soil analyses are summarized in Table 3 , and the water analyses in Table 2 . Copies of the laboratory analyses and Chain of Custody documentation are attached to this report.