2011-08-09_REVISION - M1981185 (68)

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Mining Plan Exhibit D Dry stacked tailings disposal will be implemented at the May Day Idaho Mine Complex. Disposal sites will be sited, characterized and managed as outlined in Attachment D -5. Tailings will be dewatered above ground adjacent to the mill. Tailings will be pumped in a dual - walled HDPE pipe a distance equal to or less than 50 feet to the filter press. The tailings will be conveyed to the filter press at water to solid concentration of not less than 60% and not more than 40% water. The slurry will enter a dewatering vacuum or pressure filter press (or suitable alternative) at a constant rate ranging from 35 to 45 gallons per minute (gpm) where 75 % -80% of the water will be removed. Removed water will be recycled through a 4 -inch dual - walled HDPE return pipeline to the flotation cells, dust control spray bars or the grinding cycle. The vacuum or filter press or suitable alternative dewatering equipment is located on Attachment D -2 and Figure D -1. The wet cake (solids) from the vacuum or pressure filter press will have a moisture content (less than saturation) ranging from (18 -25 %). Quality control procedures (Attachment D -8) will be implemented to demonstrate the dewatered tail is considered to be unsaturated and suitable for dry stacking. Stacking of tails will be conducted using a combination of conveyors and /or a loader. In the event the dry stacked tailing materials are subject to liquefaction, 1 -5% cement will be added to stabilize the tail thus fixating (encapsulating) available moisture in the dry stacked material. The disposal site will be located in dry, unfractured, fault free, underground mined out areas. (See Figure D -4 for disposal site options). Based upon preliminary site characterization (Attachment D -7), Wildcat has selected dry stacked tailing disposal for the following reasons: • Conserves water; • Negligible or no seepage losses from stacked tailings; • Eliminates the need to dispose of tailings on the surface; • Stabilizes the tailings mass; • Residual processing chemicals will be encapsulated in the tail; • Minimal containment requirements; • Simplifies water management; • Minimizes groundwater sampling requirements; and • Minimizes surface reclamation and long term monitoring requirements. Following retrofitting, the mill will be commissioned and a period of optimization will be undertaken as described below. Wildcat Mining Corporation May Day Idaho Mine Complex — 112d Permit Application Revised August, 2011 Exhibit D — Rule 6.4.4 Page 4 of 10