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Cripple Creek & Victor Gold Mining Company Squaw Gulch Valley Leach Facility Design <br />summarized in Table 4 and presented in Appendix B.1.2. Particle size distributions of <br />soil samples obtained from the VLF area indicate an average of approximately 30 <br />percent passing the No. 200 sieve with a range between 15 and 73 percent. The <br />results of the Atterberg limits tests indicate that the liquid limit ranges from non - plastic <br />to 55 percent, with an average of about 35 percent, a plasticity index range between <br />non - plastic and 35, with the average of approximately 18 percent, and a plastic limit <br />range between 13 and 30, with an average of about 18. <br />Possible borrow source material found within Squaw Gulch is overlain by 2 to 5 feet of <br />unsuitable material consisting of growth medium and clean sands and gravels that <br />may have to be selectively removed to intercept the proven borrow material. The <br />depth to the top of the potential borrow source material ranges from 1 to 21 feet, with <br />an average depth of 6 feet. The depth of the bottom of the borrow source is between 8 <br />and 23 feet, with an average depth of 19 feet, due to machine limits of the trackhoe. <br />The borrow source was defined by the verifiable limits of the test pits only. <br />Flexible -wall permeability testing was conducted on representative remolded samples <br />from the AMEC 2010 field investigation within Squaw Gulch. The material was first <br />sieved to remove oversize particles and then recompacted to 95 percent of the <br />standard Proctor maximum dry density at or near the optimum moisture content. The <br />flexible wall permeabilities range from between 1.3x 10 cm /sec and 5.1x 10 -8 cm /sec <br />with a geometric mean of 7.5x10: cm /sec. <br />3.4 Clay Borrow Investigation <br />A total of 54 test pits were excavated in the Squaw Clay Borrow area. The test pits <br />were excavated to depths ranging from 4 to 20 feet. The soils generally encountered <br />include 1 foot of growth medium underlain by clayey sands, clayey gravels, and lean to <br />fat clays, with few areas encountering silty sands. These soils classify as SC, GC, CL, <br />CH, and SM under the USCS. These soils were underlain by fractured bedrock <br />intercepted at depths between 4 and 20 feet, with the average interception at <br />approximately 12 feet. The majority of bedrock was segregated to the eastern and <br />western flanks of the Squaw Clay Borrow area. <br />The borrow area has been delineated on Drawing A80 and represents approximately <br />500,000 cubic yards of in -place clayey soils that may be used to produce SLF. The <br />borrow source is overlain by 2 to 5 feet of unsuitable material consisting of growth <br />medium and clean sands and gravels that may have to be selectively removed to <br />intercept the proven borrow material. Also, a portion of the potential borrow area <br />underlies the proposed future mill platform (Drawing A200), which would require <br />excavation and removal prior to construction of the mill platform. The depth of the <br />bottom of the borrow source is between 13 and 20 feet due to machine limits of the <br />trackhoe. The borrow source was defined by the verifiable limits of the test pits only. <br />Results from the geotechnical laboratory tests conducted on the soil samples obtained <br />within the clay borrow area are summarized in Table 3 and presented in Appendix <br />Project No.: 74201125G0 Page 15 <br />1 September 2011 <br />ameC° <br />