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<br />The Legend and Notes associated with the test hole logs aze shown in Figure p4. In addition, a large disturbed <br />sample of the sands and gravels was obtained from a test pit excavation previously advanced by the pit operator. <br />Measurements of the water level were made in the test holes by lowering a weighted tape into the open holes <br />shortly after the drilling was completed and 9 days subsequent to drilling. The location of the water levels <br />measured and the number of days subsequent [o drilling are shown on the logs of the test holes. <br />LABORATORY INVESTIGATION <br />~ Samples obtained from [he test holes were examined and classified in the laboratory by the project engineer. <br />Laboratory testing included standard property tests, such as natural moisture contents, dry unit weights, grain size <br />analyses and liquid and plastic limits. Unconfined compressive strength tests and direct shear testing was also <br />conducted on samples of the clays and sands and gravels to determine the shear strength of the natural soils. <br />Results of the laboratory testing program completed by our firm are summarized in Table 1 and the results of the <br />direct sheaz tests, which were completed by Advanced Terra Testing, aze shown in Appendix A. The laboratory <br />testing was conducted in general accordance with applicable ASTM specifications. <br />SUBSURFACE CONDITIONS <br />The subsurface conditions encountered in the three (3) test holes drilled for this investigation, as well as the <br />fifteen (l5) test boles previously drilled at the site for a gravel exploration study completed by the property <br />owner, indicate that the subsurface conditions are fairly uniform across the site and generally consist of a layer of <br />topsoil overlying natural clays which in turn were underlain by sands and gravels. <br />~ Namral topsoil was encountered at the surface in all of the test holes. The topsoil ranged in thickness from <br />approximately l to 2 l/2 feet. The topsoil was typically moist [o very moist and soft. <br />Natural clays were encountered below the topsoil layer and generally extended to depths ranging from 4 to 10 feet <br />below the existing ground surface in the ponion of the site to be mined. The clays were slightly sandy to sandy, <br />low to moderately plastic, medium to very stiff, moist and brown in color. The clays classified as CL soils in <br />accordance with the Unified Soil Classification System. Unconfined compressive strength tests conducted on <br />samples of the clays indicate that the unconfined compressive strengths ranged from 1,960 [0 3,350 pounds per <br />square foot (pst). These test results aze shown in Table 1. <br />• lob No. 9g-351M Northwest Colorado ConsultanLS, Inc. Page 4 <br />