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The soil boring and sampling conducted by CRC on the property site intercepted inorganic plastic clay (CL) and sandy to gravelly clay (SC) within the depth explored. CL was found in all five (5) boreholes while SC was only intercepted in boreholes 131 and B3 at the depths of 12 feet and 11.5 feet bgs, respectively. Soil type CL in boreholes B2, B4 and B5 and SC in boreholes 131 and B3 were not bottomed. The fine CL was slightly plastic (low to medium plasticity), variably silty, and relatively impervious. The SC-soil type was comprised of coarse sands and subrounded, hard gravels in clay matrix. Visual examination of the soil samples indicated no stain, odors or other features which might suggest petroleum hydrocarbon and/or VOC contamination. Groundwater was encountered in all boreholes. Depth to the groundwater ranged from 13.25 feet bgs in boreholes B 1 and B3 to 14.0 feet bgs in borehole B5. The flow gradient was toward the north-northeast which conforms with the regional trend. The type and the physical characteristics of the subsoil are described in the Soil Boring Logs (Appendix V). 4.0 PHASE II SITE INVESTIGATION ACTIVITIES 4.1 Utility Survey/Notification Prior to the site investigation, CRC located and marked on the ground the proposed five (5) boreholes. On April 17, 1995, Underground Service Alert (USA)was notified of the scheduled subsurface investigation. After inspecting the boring location, representatives of the water, telephone, gas and electrical utilities, advised CRC that the boring locations were free from underground utility lines. 4.2 Geophysical Survey At the request of CRC, Norcal Geophysical Consultants, Inc., (NORCAL) of Petaluma, California, conducted a geophysical investigation on April 19, 1995. The primary purpose of the survey was to investigate the potential presence of USTs on the subject property. The five (5) locations of the boreholes were also investigated to ascertain that no active or inactive utility lines or pipes existed at the proposed borehole locations. During the UST investigation, NORCAL used both the vertical magnetic gradient (VMAG) and the GPR methods. A 5-foot grid pattern was first established over the entire open area. Using a magnetic gradiometer (magnetometer), the earth's magnetic fields were measured on each of the grid points. The measurements were recorded, processed, and contoured as "VMAG Contour Map". The presence of buried objects, such as USTs, may be depicted as an "anomaly" which will show on the map as closely spaced contour lines forming a circular or CRC Environmental Risk Management, Inc. Project a 2100-217-2 American Savings Bank 150 West 10th Street May 1995 4 Tracy, California