2006-12-12_REVISION - M1987028 (2)

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Topsoil Stockpile Locations and Estimate of Maximum Volumes Location Est. Year Constructed Estimated Tonnage Lower Staging Area 2006-7 5000 Footwall Benches 2007-2012 20000 North End/Hangingwall 2015-20 10000 Waste Rockpiles and Process Materials Waste rock materials primarily composed primarily of course carbonaceous rock type with minor amounts of volcanic extrusive material are currently placed along the lower staging area, immediately south of the lower working piUface azea. This waste rock dump will continue to receive no grade/low grade materials for several years into the future, slowly expanding in size to the south of existing mine operations. During highwall development work over the next several yeazs, waste rock of siliceous mineral content may also be hauled to this location. It is estimated that a 1:1, W:O stripping ratio will be needed over the next several years to continue to have white marble rock available for mining. This will mean that up to 30000 tons per year may be hauled to the lower waste dump over the next several years. New affected land boundaries will allow for waste dump development well to the south of the existing dump face. However, future hangingwall development may require a lift or two (20'-30' height) of waste placement above the current lower staging area. As mining proceeds north following the marble bed, the hangingwall waste rockpile will also proceed from south to north along the eastern side of the mazble contact. The hangingwall waste rockpile will likely have breaks in the south facing outslope to facilitate roadways and drainage of the toe of the waste pile along its eastern aspect to direct all surface flow from the rockpiles and roadway into the lower pit area. Since the drainage areas in question will be limited to that area immediately east of the marble working face (all drainage within the working face of the marble bed and highwall azeas to the immediate west of the marble bed will drain into the lower pit area), drainage will simply follow the roadway system as a ditch structure along both sides of the access road from the bottom staging azea to the top mining/stockpileleuel. Rockplles below current Lower Staging Area Waste rock piles located below the current staging area elevation 10700' will not report storm flows to the lower pit. A proposed drainage plan for the ore zone and lower waste rock dumps is shown on Exhibit Cd Drainage Plan, (projected during dump construction). The sepazation berm between the waste rock dump and Taylor Gulch will be maintained. A sediment catchment basin will be constructed at the southeastern corner of the lowest dump adjacent to Taylor Gulch. The basin will hold less than one acre foot of storage, enough to contain a 25 year Type II storm over the four acres of lower dump area. Work azeas used for rip-rap production, stockpiling, and truck loading will grade west to a ditch along the roadway. The steeper runs of road ditch along the