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KEI-P89-1104 .QR1 April 19, 1991 Page 7 Selected soil and all water samples were analyzed by Sequoia Analytical Laboratory in Concord, California, for TPH as gasoline and BTX&E. In addition, the samples collected from MWl were analyzed for TPH as diesel, total oil and grease (TOG) , and EPA method 8010 constituents. Analytical results of soil samples collected from the borings for monitoring wells MW1 through MW4, indicated 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 all EPA method 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 indicated 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 all EPA method 8010 constituents were non-detectable, except for chlorobenzene and 1,2-dichloro- benzene 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 . Based on the analytical results, KEI recommended implementation of a monthly monitoring and quarterly sampling program for all wells. Documentation of well installation, sample collection and sample results are presented in KEI 's report (KEI-P89-1104 .R7) dated December 10, 1990. RECENT FIELD ACTIVITIES The four wells (MW1, MW2, MW3 and MW4) were monitored three times and sampled once during the quarter. During monitoring, the wells were checked for depth to water and presence of free product and sheen. No free product or sheen was noted in any of the wells during the quarter. Monitoring data are summarized in Table 1. Water samples were collected from the wells on March 26, 1991. Prior to sampling, the wells were purged of between 15 to 25 gallons each using a surface pump. Samples were then collected using a clean Teflon bailer. Samples were decanted into clean VOA vials and/or one liter amber bottles as appropriate which were sealed with Teflon-lined screw caps and stored in a cooler on ice until delivery to the state certified laboratory.