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KEI-P89-1104 .QR1 April 19, 1991 Page 9 varying in thickness from about 13 . 5 to 27 . 5 feet. This fine- grained sequence is inturn underlain by a second sandy zone consisting predominantly of silt sand and extending to the maximum depths explored in all wells (69 to 75 feet) . Ground water was encountered during drilling in this deeper silty sand zone only in well MW2 and was encountered approximately 2 . 5 feet above the silty sand zone in wells MW1 and MW3 and approximately 9 feet above the silty sand zone in MW4, generally within silt materials. ANALYTICAL RESULTS Ground water samples were analyzed at Sequoia Analytical Laboratory in Concord, California, and were accompanied by properly executed Chain of Custody documentation. The samples were analyzed for TPH as gasoline using EPA method 5030 in conjunction with modified 8015, and BTX&E using EPA method 8020. In addition, the ground water sample collected from MW1 was analyzed for TPH as diesel using EPA method 3510 in conjunction with modified 8015, TOG using Standard Method 5520B&F, and halogenated volatile organics using EPA method 8010. Analytical results of the ground water samples, collected from monitoring wells MW1 through MW4 , indicate non-detectable levels of TPH as gasoline and BTX&E for all samples, except for 0. 39 ppb of xylenes detected in well MW3 . In MW1, TPH as diesel, TOG and all EPA method 8010 constituents were non-detectable except for 1. 4 ppb of chlorobenzene and 5.6 ppb of 1, 2-dichlorobenzene. Results of the analyses are summarized in Table 2 . Copies of the analytical results and Chain of Custody documentation are attached to this report. DISCUSSION AND RECOMMENDATIONS Based on the analytical results collected and evaluated to date and no evidence of free product or sheen in any of the wells, KEI recommends the continuation of the current monitoring and sampling program of the existing wells per KEI ' s proposal (KEI-P89-1104 .P5) dated December 10, 1990. In addition, KEI has recently contacted Purviance Drilling for the status of the special tools necessary for proper destruction of the presently abandoned water well. The special tools have not been completed as of the date of this report. Purvxance Drilling will contact KEI and the San Joaquin County Public Health Services when the tools have been completed and the well destruction can be scheduled.