2011-03-14_REVISION - M1977493 (48)

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Permit Amendment (AM-06) - Climax Mine cM0000080 delivered to Tenmile TSF through a new tailing delivery line (TDL) that will generally follow the route of the 491 existing ETDL. The ETDL will continue to be used to route impacted water sources to the SDP. G-3.3 Fresh Water Interceptor and Bypass Systems As shown on Figure AM-06-G-02, significant changes to the fresh water interceptor and bypass facilities are not expected for the Phase I Deposition scenario. The system will remain as previously described. G-3.4 Mill Water Reclaim Systems During the Phase I Deposition period, the tailing slurry from the mill and SDP effluent will contribute process water to Tenmile TSF. The water level on Tenmile TSF can be controlled through operation of the Tenmile Decant, which conveys all flows from Tenmile TSF into the Tenmile Tunnel. Inside the tunnel, bulkhead valves can be configured to direct water south to Robinson Lake or north to Mayflower TSF. From Robinson Lake, process water will be delivered to the storage tank at the mill using the proposed Robinson Lake Pump Station and Reclaim Pipeline. This reclaim system will be sized to meet the full mill water demand with a design capacity of 10,000 gpm. Impacted water sources will continue to be routed through the SDP to receive first-stage treatment. The tailing slurry and SDP effluent will discharge into the Tenmile TSF water pool thereby completing the Phase I Deposition process water circuit. When the natural inflow to Robinson Lake is not sufficientto meet the mill water demands, the Tenmile Tunnel bulkhead valves will be opened to convey decanted water from Tenmile TSF into Robinson Lake. When the excess water in Tenmile TSF is not required at the mill or to refill Robinson Lake, the bulkhead valves will be closed to direct flows to the North Portal of the tunnel and on to Mayflower TSF where it will either be stored or treated and discharged from the property. G-3.5 Makeup Water Systems At certain times of the year, primarily during the fall and winter, precipitation runoff and SDP effluent may not be sufficient to offset consumptive uses, such as evaporation and tailing water retention. During these times, water can be discharged from storage in Tenmile TSF and Robinson Lake. The process water storage on Tenmile TSF will vary throughout the year as well as throughout the Phase I Deposition period. This capacity will generally range from about 1,000 to 3,000 acre-feet. Robinson Lake provides approximately 1,700 acre- feet of operational storage. The drainage basin tributary to Robinson Lake is relatively small and it is therefore necessary to divert water into the lake from the Tenmile Tunnel. If necessary during drought conditions, fresh water can also be diverted into the North Portal of the Tenmile Tunnel using Supply Canal No. 2. Additionally, makeup water may be diverted into Robinson Lake from the Columbine Ditch, located in the headwaters of the East Fork of the Eagle River. All waters entering Robinson Lake will have received first-stage treatment or be fresh water diversions via Supply Canal No. 2 or the Columbine Ditch. Climax recently acquired an ownership interest in the Columbine Ditch water right. The intent is to divert this water into the process water system as needed for makeup water. The diversion would require the installation of a pipeline from the ditch to Chalk Mountain Reservoir or Robinson Lake. G-3.6 Impacted Water Sources The Phase I Deposition scenario is not expected to significantly change the sources of impacted water. Impacted water will be used in the mill water circuit, which is expected to reduce the annual volume of impacted water that will be treated and discharged from the site. The additional tailing deposition in Tenmile TSF is expected to result in a minor increase of seepage flows at the toe of 3 Dam. Supernatant from the Tenmile TSF water pool will generally be re-circulated within the mill water reclaim system. G-3.7 Process Water Handling System With the exception of the mill water circuit and tailing system, the general configuration of the process water handling systems will not change significantly from that described in the Current Configuration section of this • Exhibit G G-7 May 2010