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KEI-P91-0202 .R6 January 23 , 1992 Page 6 clear and free of suspended sediment) . Monitoring and well development data are summarized in Table 1 . 4 vGc � The wells were sampled on January 3 , 1992 . Prior to sampling, monitoring data were collected, the wells were each purged of ,- P ' between 5 to 9 gallons, and water samples were then collected by the use of a clean Teflon bailer. The samples were decanted into clean glass VOA vials that were sealed with Teflon--lined screw caps, labeled, and stored, on ice, until delivery to a State certified laboratory. ANALYTICAL RESULTS Water samples from all wells, and selected soil samples from the borings of MW4 through MW9 and exploratory borings EBI and EB2 , were analyzed at Sequoia Analytical Laboratory in Concord, California. All samples analyzed were accompanied by properly executed Chain of Custody documentation. The samples were analyzed for total petroleum hydrocarbons (TPH) as gasoline by EPA method 5030 in conjunction with modified 8015, and benzene, toluene, xylenes, and ethylbenzene (BTX&E) by EPA method 8020. In addition, the soil samples collected from EBI and EB2 were analyzed for TPH as diesel using EPA method 3550 in conjunction with modified 8015, TOG by Standard Method 5520E&F, and chlorinated solvents using EPA method 8010. Analytical results of the soil samples collected from borings MW4 through MW9 indicated non-detectable levels of TPH as gasoline and BTX&E in all analyzed samples, except in sample MW6 (74) , which had a TPH as gasoline level of 5.7 ppm with a benzene level of 0.061 ppm, and in MW6 (60) , which showed a benzene level of 0. 016 ppm. In exploratory borings EBI and EB2, TPH as diesel, TOG, and EPA method 8010 constituents were non-detectable in all samples. Analytical results of the water samples collected from MW1 and MW3 through MW9 indicated non-detectable levels of TPH as gasoline and BTX&E. Analytical results of the water samples collected from MW2 indicated a level of 240 ppb of TPH as gasoline, and a level of 1 . 4 ppb of benzene. Results of the soil analyses ,are summarized in Tables 3 and 3a, and results of the water analyses are summarized in Table 2 . Copies of the laboratory analyses and Chain of Custody documentation are attached to this report. HYDROLOGY AND GEOLOGY The water table stabilized in the monitoring wells at depths ranging from 72 . 17 to 73. 65 feet below the surface, except for well . MW5, which stabilized at a depth of 61. 23 feet below grade. The higher ground water level in well MW5 is considered to be a localized condition, and was not used for calculating ground water