2008-04-15_REVISION - M1980244 (309)

Home Browse Search

• 6.0 VALLEY LEACH FACILITY EXTENSION 6.1 Introduction and General Characteristics Phase IV of the VLF was approved as part of Amendment No. 8. Construction of the Phase IV area was completed in 2004. To accommodate additional ore from the MLE, CC&V is proposing to extend the existing VLF to the east, in an area referred to as Phase 5, and to increase the ore height for the existing VLF area. The Phase 5 VLF extension will occupy approximately 138 acres. The Phase 5 VLF design extends the VLF into upper Arequa Gulch, onto the northwest slopes of Squaw Mountain and over the regraded AGOSA. Phase 5 includes construction of a dedicated pregnant solution storage area ("PSSA") for the VLF extension, and increases the maximum ore height at select locations within the existing VLF from 590 feet to approximately 800 feet. The maximum ore height in the Phase 5 VLF will be about 590 feet. The Phase 5 extension will consist of an additional 6 million square feet of lined area for ore storage (plan view area) Construction of the Phase 5 base and liner systems is anticipated to begin in 2009 with • site clearing and is anticipated to be completed by 2011. The actual construction schedule could vary from that presented above depending on various factors, with weather during the normal construction season being an important consideration. Phase 5 of the VLF is designed and will be constructed in a similar manner to previous Phases. Liner systems for the Phase 5 VLF area will consist of the same containment features as those approved for previous phases of the VLF. A fourth internal PSSA will be constructed for Phase 5. The PSSA will be formed along the eastern edge of the Phase IV VLF with a containment berm at the southern or downgradient edge of the Phase 5 VLF. Pregnant solution generated during leaching of the Phase 5 extension area will be contained within the Phase 5 VLF internal PSSA. Where the Phase 5 ore overlaps onto the existing VLF, some pregnant solutions will report to the Phases I and II PSSAs. A surface water diversion system has been designed for the Phase 5 extension and is sized to divert upgradient surface water flows generated from the 100-year, 24-hour storm event. Where needed, sedimentation ponds have also been included in the design. Appendix 8, Volumes V and VI of this document, contains the design document for the • Phase 5 VLF prepared by Smith Williams Consultants, Inc. The following sections Cripple Creek & Victor Gold Mining Company Cresson Project Mine Life Extension 6-1