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Cripple Creek & Victor Gold Mining Company Squaw Gulch Valley Leach Facility Design <br />3.0 SITE SUBSURFACE CONDITIONS <br />3.1 Previous Site Investigations <br />An initial site investigation for the Squaw Gulch VLF area was conducted by Golder <br />(2007). This investigation focused on the general subsurface conditions within the <br />proposed VLF. In addition, the report presents the results of a clay borrow <br />investigation completed in Squaw Gulch, Vindicator Valley, Globe Hill, and the Bull Hill <br />area. <br />SWC completed an extensive geotechnical field investigation to further characterize <br />the VLF foundation. Additionally, a detailed clay borrow source program was <br />conducted in the Bull Hill area to further delineate and qualify a source for the SLF. <br />The geotechnical investigation included test pit excavations and advancing core holes <br />in critical areas for the VLF design. A total of 123 test pits were excavated from May <br />25 through June 6, 2007 within the Squaw Gulch and Bull Hill areas. The test pits <br />were excavated by Conley Construction using a Komatsu C200 trackhoe, a Case <br />9040B trackhoe, and a Case 590 backhoe. SWC personnel supervised and logged <br />each test pit and collected soil samples for laboratory testing. <br />Three core holes were advanced within the limits of the proposed PSSA between May <br />14 and 17, 2007. The boreholes were drilled and cored by Ager Drilling with a track - <br />mounted CME 45. SWC personnel supervised each core hole and collected samples <br />for subsequent geotechnical testing, where appropriate. The SWC geotechnical logs <br />of the test pits and core holes are presented in Appendix A.1. The results of the <br />geotechnical laboratory tests completed by SWC are presented in Appendix B.1.1. <br />3.2 Current Site Investigation <br />AMEC completed an additional geotechnical field investigation to further characterize <br />the area of the proposed VLF foundation. The geotechnical investigation included the <br />excavation of 65 test pits. These test pits were excavated from June 15 through 26, <br />2010 within the VLF footprint. The test pits were excavated by Conley Construction <br />using a Case 9040B trackhoe. AMEC personnel supervised and logged each test pit <br />and collected soil samples for subsequent geotechnical laboratory testing. <br />The geotechnical logs of the AMEC test pits are presented in Appendix A.2. The <br />results of the AMEC geotechnical laboratory tests are presented in Appendix B.1.2. <br />The following section presents a summary of the site geotechnical conditions. <br />3.3 Site Geotechnical Conditions <br />A total of 134 test pits were excavated in the area of the proposed VLF footprint (refer <br />to Drawing A20 for locations). These test pits were excavated to depths ranging from <br />approximately 3 to 23 feet. After completion, the test pits were reclaimed by backfilling <br />with the excavated material. The soils encountered in the test pits generally consisted <br />Project No.: 74201125G0 Page 13 <br />1 September 2011 <br />amec <br />