2012-02-28_REVISION - M1980244 (104)

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12.4.3 Arequa Gulch VLF and Squaw Gulch VLF Reclamation procedures of both the SGVLF and the AGVLF will occur as previously approved under MLE for AGVLF. The VLFs will be rinsed, outslopes will be regraded, soil will be placed and revegetation performed. Each of these steps is discussed below. Active leaching for gold recovery is expected to be completed for the AGVLF in approximately 2024, and for the SGVLF in approximately 2033. After completion of active leaching, the VLFs will be rinsed in the same manner as previously approved. Two rinsing cycles, using recirculated solution and fresh water, will require about 30 months to complete. It is proposed this will be followed by a hydrogen peroxide (H202) assisted rinsing cycle to complete removal of cyanide (the need for this H202 rinse will be evaluated during VLF rinsing). The financial warranty is based on two standard water rinsing cycles and one H202 rinsing cycle over an approximate six -year period. The rinsing procedure will employ a rinse -rest strategy as previously approved. The VLFs will be rinsed in segments with portions being actively rinsed while other areas are allowed to "rest." Rinse water and H202 will be circulated using the VLF pumping systems at a pumping rate of approximately 28,000 gpm. Rinsing criteria previously approved for the VLFs is an average concentration of 0.2 mg/L CN in the rinsate from meteoric water mobility testing on representative sampling of the spent ore, or in return flows derived from the neutralized ore, or both. A four -year monitoring period will follow the rinsing to demonstrate compliance with the standard. Physical reclamation of the VLFs will be completed in approximately 2 -years and start concurrent with the monitoring period. Upon achieving the CNwA removal criteria, the VLF liner systems will be breached in the same manner as previously approved. The liner will be perforated to prevent excessive accumulation of storm water infiltration in the neutralized ore behind the toe berms and to move meteoric draindown storm water into the underlying diatreme rock. It is anticipated that a drill rig will be utilized to drill from the surface of the ore on the VLFs through the synthetic and clay liners into the closure drains and underdrains, where appropriate. Holes will be drilled to puncture the liner above these features installed at several locations beneath the PSSAs. This will allow conveyance of post- reclamation precipitation through the material on the VLFs and into the underlying diatreme rocks. Following the achievement of the CN removal criteria for both VLFs and following the breaching of the liner systems (as discussed above), all down- gradient appurtenances will be reclaimed as follows. Cripple Creek & Victor Gold Mining Company Cresson Project Mine Life Extension 2 12 -15