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i ~ • The test holes were advanced through the overburden soils with aall-terrain mounted CME 55 drill rig utilizing both 4-inch diameter continuous flight and 7-inch diameter hollow stem power augers. The test pits were excavated with a Cat 416B backhoe. The test holes and pits were logged by a representative of NWCC, Inc. Samples of the subsurface materials were taken with either withal 3/8-inch split spoon sampler or were obtained from auger cuttings obtained during drilling. The split spoon samples were obtained by driving the sampler into the vazious strata with blows from a 140-pound hammer falling 30 inches. This test is similar to the standazd penetration test described by ASTM Method D1586. Penetration values, when properly evaluated, indicate the relative density or consistency of the soils. Depths at which the samples were taken and the penetration values are shown on the logs of the exploratory test pits and holes in Figures #3 through #5. The Legend and Notes associated with the test pit and hole logs are shown in Figures #6 and #7, respectively. Measurements of the water level were made in the test holes by lowering a weighted tape into the open holes shonly after the drilling was completed or during excavation of the test pits. The location of the water levels measured are shown on the logs of [he test pits and hales. [t should be noted that slotted PVC casing, l 1/2-inch diameter, was placed in the upper 10 feet of four of the test holes so that the groundwater levels can be monitored. LABORATORY INVESTIGATION • Samples obtained from the test holes and pits were examined and classified in the laboratory by the project engineer. Laboratory testing included standazd property tests, such as natural moisture contents, dry unit weights, grain size analyses and liquid and plastic limits. Unconfined compressive strength tests and direct sheaz testing was also conducted on samples of the overburden soils and the sands and gravels [o determine [he sheaz strength pazameters of these materials. Results of the laboratory testing program completed by our firm aze summarized in Table 1 and the results of [he direct sheaz tests, which were completed by Knight Piesold Laboratory, are shown in Appendix A. The laboratory testing was conducted in general accordance with applicable ASTM specifications. SUBSURFACE CONDITIONS The subsurface conditions encountered in the eight (8) test holes drilled and the four (4) test pits excavated for this investigation, as well as the nine (9) test holes previously drilled at the site for a gravel exploration study completed for the client, indicate that the subsurface conditions aze fairly uniform across the site and generally consist of a layer of overbank deposits consisting of topsoil, silts and clays overlying natural sands and gravels and claystone-shale bedrock [o the maximum depth explored, 40 fee[. . A layer of topsoil and silt was encountered at the ground surface in all of the test holes and pits and generally varied from 2 to 6.5 feet in thickness. These materials were clayey to sandy, fine grained with occasional gravels, lob No. 00431M Nonhwes[ Colorado Consultants, Inc. Page 3