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C maximum depth explored at the site..Soils encountered near the former dispenser area(borings B5- 4 and B5-5) comprise mostly clay. A 1- to 2-foot thick bed of sand occurs beneath the former dispenser area at about 17 feet bgs. 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 this and other Port sites (dating back to 1987) indicate that no groundwater was encountered during excavation of tanks 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 E1 Nino rainfall events of last winter. The static water level in the borings emplaced near the former USTs(borings B5-1 to-3)was about 9 feet bgs on August 5,while water levels in the borings emplaced near the former dispenser area(borings B54 and-5) were about 11 feet bgs. Based on nearby studies(SPGC, 1998, and 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 ACTPVfrlES 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 nnigrate 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 borings was provided by Geomatrix Consultants, Inc. of Fresno, California. The borings were drilled using a CME-75 drill rig.:Prior to drilling operations,Underground Services Alert was i contacted and underground utilities marked by respective utility companies. In addition,the Port's tmaintenance 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 constructed on May 17, 1999. Wells MW5-1 and MW5-2 are located within 3 feet of previous borings B 5-1 and B5-5;respectively L (Figure 2). No soil samples were collected from the borings for these wells ,because of their proximity to previous borings, from which samples were collected to depths of 26 and 20 feet 4 PHILIP P. Ross �s s R.G.