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i depth of about 20 feet bgs comprised of interbedded sands and clays, mostly under reduced conditions (Sierra-Pacific Groundwater Consultants [SPCC], 1994). Lithologic data from Site 2 (borings B2-1 and B2-2 [Appendix A]) indicate a predominance of ' silt and clay to a depth of about 15 feet bgs, with silty sand to 21 feet bgs, the maximum depth explored at Site 2 Lithologic and hydrologic data at Site 3, together analytical data from soil and groundwater samples, are depicted on the geologic cross section presented on Figure 4 The cross-section extends approximately 30 feet, from boring B3-2 on the northwest to boring B3-1 on the southeast. Data from boring B3-3 is projected approximately 20 feet northeast onto the plane of the cross section The cross section indicates that, in general, the interval from roughly 13 to 23 feet bgs beneath the former tanks at Site 3 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 bgs, the total depth explored during tlus ' investigation Data from nearby studies indicate that the current depth to groundwater in the vicinity ranges ' from about 5 to 10 feet bgs (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 bgs. Water levels in this area have risen as much as 8 feet nice 1994, 2 to 3 feet of which appear to be attributable to the heavy and prolonged El Nano rainfalls of last winter The static water level measured in borings B2-1 and B2-2 at Site 2 ranged from about 8 5 to 9 feet bgs on August 6 (Appendix A) Water levels measured in the three borings at Site 3 on August 7 ' ranged-from about 9.5-to 12-feefbgs(Appendix A);-=Based-on nearby=studies-(SPGC;-1998= -- ---- &-EMCON,-1998)-groundwater.flow directions-in_the vnciuty appear_to_be vanable,-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 area. ' 4.2 SOII. AND GROUNDWATER ANALYTICAL RESULTS Analytical results for soil and groundwater samples at Sites 2 and 3 collected during this investigation are presented on Tables 2 and 3, respectively. The laboratory data sheets and chain-of-custody records are included in Appendix B. The results from each of the two sites are discussed in the following sections ' 8 98117UNVRPT3%3 sUsnN RPT 1 1