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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 this investigation Data from nearby studies indicate that the current depth to groundwater in the vicinity ranges from about 5 to 10 feet bgs(SPDC, 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 since 1994, 2 to 3 feet of which appear to be attributable to the heavy and prolonged El Nino rainfalls of last winter Water levels measured in the three initial borings at Site ' 3 on August 7, 1998 ranged from about 9 5 to 12 feet bgs 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 3.0 SUMMARY OF ACTIVITIES Activities during this investigation included installation and development of monitoring wells, sampling of monitoring wells, elevation survey of monitoring wells, and completion of a survey of ' nearby supply wells that could be affected if contamination were to migrate off site All activities were conducted in general accordance with procedures described in the work plan 3.1 INSTALLATION OF MONITORING WELLS Monitoring well installation services were provided by West Hazmat Drilling Corporation (West Hazmat)of Rancho Cordova, California, a C-57 licensed drilling contractor, and geologic logging ' of the bonngs was provided by Geomatnx Consultants, Inc of Fresno, California and Philip P Ross, R G The boring for MW3-3 was drilled using a CME-75 drill ng, and borings for MM3-1 ' and MW3-2 were drilled with a track-mounted hmited-access hollow stem auger rig Prior to drilling operations, Underground Services Alert was contacted and underground utilities marked by respective utility companies In addition, the Port's maintenance department was notified and ' they examined the site for underground utilities West Hazmat obtained an approved monitoring well installation permit from PHS/EHD (Appendix A) and monitoring wells were constricted on May 18, June 1, and June 2, 1999 vrrn-wim 4 PHILIP P. Ross, R.G.