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Response to Preliminary County Comments Received on March 17, 2011 <br />Response #17 <br />The revised portal collapse repair work plan has been incorporated in Attachment E-4.- <br />Exhibit 6.5 and addresses Mr. Tim Cazier's adequacy issues. <br />Adequacy Issue #18 <br />Under the "Mill Retrofit and Commissioning" portion of Exhibit D, the application discusses the <br />installation of a 700 foot long pipeline to transport tailings from the mill to the underground <br />disposal location. Other parts of the application state the tailings will be dewatered prior to <br />disposal. Please clarify how the Operator intends to pump dewatered tailings through the 700 <br />foot long pipeline. <br />Response #18 <br />The use of a 700 foot long pipeline is not currently proposed. Slurried tails will be <br />conveyed to a filter press or suitable alterative that will be located on the May Day No. 1 <br />bench. The dual lined slurry pipeline and recycled water return pipe line will be less than <br />50 feet long. The pipelines will be located at the mill process discharge point to the tailings <br />dewatering equipment. <br />Dry stacked tailings disposal will be implemented at the May Day Idaho Mine Complex <br />(See Figure D-la for disposal site options). Tailings (150-200 mesh grind) will be dewatered <br />after the material is transported to the approved disposal location. (Dry stope/old workings <br />are located above the water table). The 4-6 inch pipeline, disposal site and the dewatering <br />and disposal process are described in the revised Exhibit D Mine Plan. In summary tailings <br />will be transported using piston pumps via a HDPE pipeline to the discharge point at <br />water to solid concentration of not less than 60% water and not more than 40% water. <br />The slurry will enter a dewatering vacuum or pressure filter press or suitable alterative at <br />a constant rate ranging from 35 to 45 gallons per minute (gpm) which will remove 75%- <br />80% of the water. Removed water will be recycled through a 4 inch HDPE return pipeline <br />to the flotation cells. The wet cake (solids) from the vacuum or pressure filter press will <br />have a moisture content (less than saturation) ranging from (18-25%). Qualitv control <br />procedures will be implemented to demonstrate the dewatered tail is considered to be <br />unsaturated (solid) and suitable for dry stacking. Stacking of tails will be conducted using a <br />combination of conveyors and/or front end loader. <br />In the event the materials are subiect to liquefaction, 1-5 % cement will be added to <br />stabilize the tail thus fixating available moisture in the dry stacked material. <br />Revised <br />4/14/2011 <br />11