Laserfiche WebLink
Cripple Creek & Victor Gold Mining Company Squaw Gulch Valley Leach Facility Design <br />foot thick layer of drainage gravel (underdrain fill) enclosed in a geotextile. During the <br />closure period, after the PSSA water level has been reduced to a maximum level of 8 <br />feet, the PSSA liner system will be punctured by drilling a borehole through the PSSA <br />and into the blanket drain. This will facilitate long -term drainage of the PSSA. <br />The second component of the closure underdrain is passive drainage of water from the <br />VLF into the diatreme present beneath the facility. During construction of the closure <br />drain during Phase 1 construction of the VLF, drilled shafts will be advanced a <br />minimum of 10 feet into the diatreme foundation. <br />4.15 Technical Specifications <br />Technical specifications for the Squaw Gulch VLF are provided in Appendix H. The <br />specifications are based on the currently approved specifications by the OMLR in <br />connection with Amendment Nos. 6, 7, 8, and 9 (CC &V, 1993a, 1998, 2000, 2008), <br />with the following modifications made during Phase 5 construction of the Cresson VLF: <br />• Modification of the plasticity index (PI) from 5 to 15 for the Fine Shaft Backfill <br />(FSB), Pipe Bedding, and Granular Filter materials (AMEC 2009); and <br />• An increase in the maximum fines content (percent passing the No. 200 sieve) <br />from 50 to 65 percent for the Soil Liner Fill (SLF) materials (AMEC 2010). <br />Project No.: 74201125G0 Page 26 <br />1 September 2011 <br />amec'3 <br />