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Soil samples were collected for lithologic description and chemical analysis from the borings at five- foot intervals using a Cal-modified split spoon sampler Soil sample tubes selected for laboratory analysis were covered with Teflon tape, capped, labeled, entered onto a Cham-of-Custody record, and stored in a cooler with ice The samples were transported to VOC Analytical (VOC) a state-certified environmental laboratory located in Concord, California, for analysis The soil samples were analyzed for Total Purgeable Petroleum Hydrocarbons (TPPH) according to EPA Method 8015 (Modified), and benzene, toluene, ethylbenzene, xylenes (BTEX), and methyl- tertiary-butyl-ether according to EPA Method 8020 Additionally, soil samples from MW-1 l were analyzed for oxygenate compounds by EPA Method 8260 Soil Stockpile Soil generated during drilling activities was placed in a stockpile at the subject site The soil was placed on and covered with visqueen Soil samples were collected from the stockpile and analyzed for TPPH, BTEX and TTLC lead The soil was profiled to Forward Landfill in Manteca, California and was transported there on December 16, 1997 by Manley and Sons Trucking for disposal Monitoring Well Installations- Borings MW-9, MW-10, and MW-11 were completed as ground water monitoring wells constructed of 2-inch diameter threaded Schedule 40 PVC well casing Well screen was placed in the first encountered water bearing zone from 5 to 20 feet below grade (fbg) in each well Well construction included the placement of filter pack sand across the screened interval and one foot above the top of the screen interval A one foot thick bentonite seal was placed above the sandpack followed by a cement-grout seal to grade Each well was secured with a locking well plug and a vault box Well completion details are presented in Table 1 and on the exploratory boring logs contained in Appendix B The elevations of the newly installed wells have been surveyed by a licensed surveyor relative to the existing site wells The top of casing and top of vault box elevations for each of the new wells were surveyed to the nearest 0 01 foot On December 2, 1997, Blaine Tech Services (Blaine) of San Jose, California developed Wells MW-9, MW-10, and MW-11 by surging and purging the wells and pumping 10 casing volumes from each well Findings Geology and Hydrogeology Lithology encountered during the drilling of the exploratory soil borings consisted of clay, silt, and silty sand, to a depth of approximately 21 fbg First encountered ground water occurred in the borings at depths of 10 to 16 fbg Ground water in the wells later stabilized at approximately b to 10 8 fbg 240-0783 1 i