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1990) Data from nearby studies within the Port area indicate a soil profile to a depth of about 20 feet bsg consisting of interbedded sands and clays, mostly under reduced conditions (Sierra-Pacific ' Groundwater Consultants [SPGC], 1994) Lithologic data at Site 3 indicate that,in general, the interval from roughly 13 to 23 feet bsg beneath ' the former tanks comprises mostly silt, clayey silt, and clay Silty sand occurs below this interval, which grades downward into loose, dark gray to greenish-gray, poorly-graded sand This dark gray sand was observed in all three borings from approximately 30 to 41 feet bsg, the total depth ' explored Data from nearby studies indicate that the current depth to groundwater in the vicinity ranges from about 5 to 10 feet bsg. (SPGC, 1998, and EMCON, 1998) Seasonal fluctuations in the water table ' appear to range from about 3 to 5 feet, with some as much as 6 to 9 feet Tank removal inspection records for Port sites (dating back to 1987) indicate that no groundwater was encountered during ' excavation or soil resampling to a depth of as much as 16 feet bsg Water levels in this area have risen as much as 8 feet since 1994, 2 to 3 feet of which appear to be attributable to the heavy and prolonged El Nino rainfalls the winter of 1997 Water levels measured in the three initial borings at Site 3 on August 7, 1998 ranged from about 9 5 to 12 feet bsg Based on nearby studies (SPGC, 1998 & EMCON, 1998) groundwater flow directions in the vicinity appear to be variable, ranging from west northwest to east southeast Flow direction changes may be due to tidal influences produced by the deep water channel to the north and the San Joaquin River to the west and southwest of the Port complex HISTORY OF SITE WORK ' 1988 During removal of two underground storage tanks (USTs) in 1988, approximately 180 cubic yards of soil were excavated with the tanks to a depth of about 11 feet bgs (Boyajian & Ross, 1998) Discolored gray soil with strong petroleum odors was observed at the southern ends of the tanks Soil samples were collected near the ends of the USTs from depths of approximately ' 13 and 16 feet bgs No groundwater was encountered during excavation or sampling to a depth of 16 feet bgs These soil samples were analyzed for total petroleum hydrocarbons quantified as gasoline (TPHg) and total petroleum hydrocarbons quantified as diesel using United States Environmental Protection Agency(EPA) Method 8020 Selected samples were analyzed for ethylene dibromnde ' (EDB)using EPA Method 8010, and for total lead Analytical results indicated low levels of petroleum hydrocarbon compounds (PHCs) in the soil samples, primarily those collected at the south ends of the tanks PHC concentrations in the 16-foot samples were significantly lower than 1 those of the 13-foot samples EDB was not detected in these samples Lead was detected at 6 to 12 4 milligrams per kilogram in the 13-foot samples collected from the north ends of both tanks, but was not detected in the samples collected at 16 feet bgs ' ust stte3 qtr]3 doe 2 1