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2. Field Investigation 3. Laboratory Analyses 4. Investigation-Derived Waste Disposal 5. Site Investigation Report Preparation 3.1 Task 1: Permitting and Mobilization Permits for the soil and groundwater investigation will be obtained from the San Joaquin County Public Works Agency (SJCPWA). Access agreements will be obtained for proposed investigation points on private land. Underground Service Alert will be notified of the subsurface investigation at least 48 hours prior to initiation of the investigation. 3.2 Task 2: Field Investigation This task will include the advancement of 12 Cone Penetrometer Test (CPT) points and the collection of groundwater grab samples at each of the CPT points. The area north of the site was delineated by a 500 foot grid originating at the southeast corner of the site. CPT locations were selected, based on the grid spacing, to provide data for systematic evaluation of subsurface conditions. The locations for the CPT points/groundwater sample locations are shown in Figure 2. CPT and groundwater sampling procedures are presented in Appendix A. 3.2.1 Cone Penetration Testing Twelve CPT points will be advanced to determine the nature and sequence of subsurface strata, groundwater conditions, and the physical and mechanical properties of the subsurface strata. The CPT methodology will provide a near continuous profile of soil type and detailed stratigraphy information using tip resistance and sidewall friction. CPT points will also provide measurement of equilibrium pore pressure which can be used to evaluate the direction of groundwater flow and vertical pressure head distribution. The projected depth of each of the CPT sounding is between 80 and 100 feet BGS. This projected depth is expected to encounter the upper groundwater zone previously sampled in the 1994 geoprobe investigations and will approach the depth of the screened interval of the domestic wells in the area. The actual total CPT depth will be determined by field conditions. All CPT equipment will be washed prior to advancement and between points. CPT holes will be grouted upon completion. Waste generated during the field investigation will be stored in 208-liter (55-gallon) drums approved by the United Nations for transport of liquid and solid wastes, and disposed of under Task 4. 3.2.2 Groundwater Grab Sample Collection Groundwater grab samples will be collected from the 12 CPT locations. Groundwater grab sample locations were selected to provide data for systematic evaluation of groundwater conditions. Based on previous investigations in the area of the site, the first groundwater interval is expected to be encountered at a depth of approximately 10 to 15 feet BGS. If a second and/or third groundwater Work Plan IT Corporation 4 All Pure,Tracy