2008-04-15_REVISION - M1980244 (351)

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• During periods of temporary cessation, CC&V will maintain adequate staff to continue to circulate solutions and monitor and maintain water balances. Power and back-up power will be maintained. No cyanide will be added during those periods. All monitoring and associated reporting activities also will continue during temporary cessation. 13.7 Facilities Evaluation The facilities associated with MLE ore beneficiation have been designed in accordance with OMLR/MLRB-accepted criteria. Section 4.0 of the Project Description contains information on site-specific conditions including geology, climatology, ground water, and surface water. As noted earlier, details about designated chemical storage may be reviewed in Section 6 and 7 of this Project Description and the SPCC Plan in Appendix 12, Volume VII. The VLF is a zero discharge facility and will employ after implementation of the MLE four internal PSSAs (Phases I, II, IV, and 5). Solution within the PSSAs is piped to the beneficiation facilities at the ADR. The ore storage liner system consists of a minimum one-foot thick SLF with a maximum permeability of 1x10-6 cm/sec placed on a prepared surface and overlain by an 80-mil single-sided textured (texture side down) LLDPE • geomembrane, which is then overlain by a leachate collection system embedded in at least 2 feet of DCF. The liner system within the PSSA will consist of a minimum of one- foot thick SLF, overlain by a 100-mil LLDPE geomembrane liner (textured on both sides), overlain by three feet of LVSCS fill, overlain by a 100-mil smooth LLDPE, overlain by a minimum two feet of DCF, with thicker DCF over primary solution collection pipes. The liner system on the PSSA embankment slope will be the same as within the PSSA except that the 100-mil LLDPE geomembrane liners be textured on both sides. The LVSCS is continuously monitored and pumped to ensure that less than two feet of hydraulic head is placed on the second synthetic liner. The entire VLF area is underlain by a leak detection system placed on the graded and prepared surface prior to placement of the SLF. The PSSAs have adequate storage to handle the operating solution level, the 12-hour draindown level if there is no pumping of solution from the PSSAs, precipitation from a 100-year 24-hour storm event, 95 percent of the mean monthly precipitation at the site, solution retained in the field capacity of the ore contained within the PSSA, as well as 5 feet of freeboard. The Phase 5 PSSA also has a design capacity 10 million gallons greater than required for operation. Design specifications associated with the VLF may be reviewed in greater detail in Appendix 8, Volumes V through VI. • Cripple Creek & Victor Gold Mining Company Cresson Project Mine Life Extension 13-7