2009-11-13_PERMIT FILE - C1982056 (3)

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The test holes were advanced through the existing reclaim fill materials with 4 -inch diameter continuous flight augers. The test holes were advanced with an all- terrain rig mounted with a CME 55 drill rig to depths ranging from 25 to 40 feet below the existing ground surface. A representative of NWCC, Inc. logged the test holes. Samples of the subsurface materials in the test holes were taken with either a California Liner sampler or a standard split spoon sampler. The samplers were driven into the various strata with blows from a 140 - pound hammer falling 30 inches. This test is similar to the standard penetration test described by ASTM Method D -1586. Penetration resistance values, when properly evaluated, indicate the relative density or consistency of the soils and bedrock materials. Depths at which the samples were taken and the penetration resistance values are shown on the logs of the exploratory test holes in Figure #3. The test pits were excavated with a Cat 315B trackhoe. The test pits were excavated in the upper 10 to 11'1 feet of the existing reclaim fill materials. A representative of NWCC, Inc. logged the test holes. Large bulk samples of the reclaim fill materials were obtained as the test pits were excavated. Graphic logs of the exploratory test pits are shown in Figure #4. The Legend and Notes associated with the test hole and test pit logs are shown in Figure #5. Laboratory Investigation • Samples obtained from the test holes and test pits were examined and classified in the laboratory by the project engineer. The laboratory testing included standard index property tests, such as natural moisture contents, density, grain size analyses and liquid and plastic limits. Swell- consolidation tests were also conducted on relatively undisturbed samples of the reclaim fill materials to determine the swell - consolidation potential of these materials. Moisture - density relationships using Standard Proctor tests were conducted on the large bulk samples obtained from the test pits. Unconfined - compressive (U -U) strength tests were conducted on samples of the in -place reclaim fill materials obtained from the test holes, as well as remolded samples obtained from the Standard Proctor tests. A bulk sample of the reclaim materials was delivered to Knight Piesold Consulting for triaxial shear testing. Consolidated - undrained (C -U) with pore pressure shear strength testing was performed on remolded samples of the reclaim fill materials. It should be noted that the reclaim spoils contain a significant percentage of cobbles and boulders, which cannot be included in conventional test samples. A summary of the standard index properties and unconfined compressive strengths from the samples obtained from the test holes are summarized in the attached Table 1. A summary of the standard index properties and unconfined compressive strengths from the remolded samples are summarized in the attached Table 2. Tables 1 and 2 along with the Standard Proctor test results, swell - consolidation test results and tri- axial shear strength test results are presented in Appendix A. All of the laboratory testing was conducted in general accordance with applicable ASTM specifications. • Job Number: 08 -7915 NWCC, Inc. Page 4 Revised 10/12/09