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KEI-P88-1013 R6 May 22 , 1996 Page 2 drilled, constructed, and completed in accordance with the guidelines of the RWQCB and the California Well Standards (per Bulletin 74-90) The subsurface materials penetrated and details of the construction of the wells are described in the attached Boring Logs and well Construct n onstruct1pn Diagrams, respectively tonitoring wells MW16 and MW17 were each drilled and completed to otal depths of 64 and 65 feet below grade, respectively Ground ater was encountered during drilling of wells MW16 and MW17 at depths of 52 5 and 53 5 feet below grade, respectively Soil samples were collected for laboratory analysis and for lithologic logging purposes at a maximum spacing of 5 foot intervals, at significant changes in lithology, at obvious areas of contamina- tion, and at or within the soil/ground water interface, beginning at a depth of approximately 5 feet below grade and continuing until ground water was encountered. Soil sampling conducted bel/w the ground water table was for lithologic logging purposes only The undisturbed soil samples were collected by driving a California- modified split-spoon sampler (lined with brass liners) ahead of the drilling augers The two-inch diameter brass liners holding the samples were sealed with Teflon-lined plastic caps, labeled, and placed in individually sealed plastic bags, which were then stored in a cooler, on ice, until delivery to a state-certified labora- tory Each new well casing was installed with a watertight cap and padlock A round, watertight, flush-mounted well cover was cemented in place over each new well casing The surface of each new well cover and the top of each new well casing were surveyed by Kier & Wright of Pleasanton, California, to Mean Sea Level (MSL) and to a vertical accuracy of 0 01 foot Monitoring wells MW16 and MW17 were developed on December 13 and 15, 1995 Prior to development, the wells were checked for the depth to the water table and the presence of free product No free product was noted in either of the new wells After recording the monitoring data, MW1Y and MW17 were purged (using a submersible pump) of 68 and 152 gallons of water, respectively, until the evacuated water was clear and free of visible suspended sediment All of cne Unocal wells, including the newly installed we'is VIVIivv and MW17, were monitored and sampled on December 19 , 1995 , by MPDS Services, Inc , of Concord, California The ground water samples were analyzed for total petroleum hydrocarbons (TPH) as gasoline and benzene, toluene, ethylbenzene, and xylenes (BTEX) The monitoring and well development data for the Unocal wells are summarized in Table 1, the field parameter data are summarized in Table 2 , and the analytical results of the ground water samples are 40 summarized 3n Table 3