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KLEINFELDER To assess the vadose zone characteristics outside of the landfill perimeter, two pilot borings (B-3 and B-4)were drilled, logged, and sampled to a depth of 100 feet. Detailed logs of the upper 50 feet of soil were obtained by continuously coring the borings. After approximately 50 feet, samples were collected and logged every 5 or 10 feet to the termination depths of 100 feet. 3.1.2 Logging The borings were logged using both the Unified Soil Classification System (USCS) to describe unconsolidated material and the rock classification system to describe consolidated materials. The USCS and rock classification systems are shown on Plates B-1 and B-2,Appendix B. The upper 50 feet of B-3 and B-4 were logged by alternating a 5-foot continuous core run with an 18-inch drive sample. The drive sample was used to collect soil for potential chemical and physical analysis. Below the 50-foot depth in B-3 and B-4 and beneath the fill contact in B-1 and B-2, drive samples were collected every 5 or 10 feet for lithologic logging. Boring logs are presented in Appendix B. 3.1.3 Sampling Two soil samples were collected to assess the pore fluid chemistry of the vadose zone beneath the landfill, following the protocol outlined in Appendix A. The two samples were chosen based upon a correlatable stratigraphic sand unit for comparison of the data. One sample was collected from B-1, at a depth of 75.5 feet, approximately 10 feet below the bottom of the fill material. The second sample was collected from B-2, at a depth of 56 feet, approximately 20 feet below the bottom of the fill material. One soil sample, collected from a depth of 33.5 feet in B-4, was selected to represent approximately the same lithology in a background location unlikely to be affected by the landfill. Nine samples were selected from B-3 and B-4 to assess permeability of the vadose zone soils. A log of the samples collected for analysis is presented on Table 3-1. FOOTHILL 17