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. KEI-P88-1013 R6 May 22 , 1996 Page 3 A point monitoring event was also conducted with the nearby Montgomery Ward site on December 19 , 1995 The monitoring data and the analytical results for the Montgomery Ward monitoring wells (provided by Environmental Audit, Inc ) are summarized in Table 4 ANALYTICAL RESULTS Selected soil samples collected from the boring of monitoring wells MW16 and MW17 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 TPH as gasoline by EPA method 5030/modified 8015 , and BTEX by EPA method 8020 The analytical results of the soil samples are summarized in Table 5 Copies of the laboratory analyses and the Chain of Custody documentation for the soil samples are attached to this report The analytical results of all of the ground water samples collected from the Unocal monitoring wells (MW10 through MW17) to date are summarized in Table 3 The concentrations of TPH as gasoline and benzene detected in ground water samples collected on December 19 , 1995 , are shown on the attached Figure 2 Copies of the laboratory analyses and the Chain of Custody documentation for the water samples collected on December 19 , 1995 , are attached to MPDS Services, Inc Quarterly Data Report (MPDS-UN5098-09) dated January 24 , 1996 HYDROLOGY AND GEOLOGY On December 19, 1995 , the measured depth to ground water in the Unocal moni rang we is ranged from 46 13 to 47 55 feet below the top of the well casings The ground water flow direction at the Unocal and the adjacent Montgomery Ward s�rte on December 19 , 1995 , appeared to be predominantly to the east,✓ as shown on the attached Figure 1 The ground water flow direction has varied from the east to the south-southwest during the 15 previous quarters of monitor- ing and sampling The hydraulic gradient at the site and vicinity on December 19 , 1995 , was approximately0based on water level data collected from the Unocal monitoring wells prior to purging The subjecz size is locazeu aujacenz Lo zlle baC.Latilellcu-Scul Joaquli1 delta in the Central Valley geomorphic province The Central Valley is a large, northwestward-trending, asymmetric structural trough that has been filled with as much as six vertical miles of sediment in the San Joaquin Valley. Based on review of regional geologic maps (U S Geological Survey Miscellaneous Field Studies Map MF-1401 "Geologic Maps of the Sacramento-San Joaquin Delta, California" by Brian F Atwater, 1982 ) , the subject site is underlain by Holocene and/or upper Pleistocene alluvium identified as Alluvium of Calaveras River and Vicinity (Qcr) The Calaveras