2012-10-01_REVISION - M1977311 (12)

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Mine Access The main portal to be used will be the northern adit that is currently closed with a bat gate. The portal is driven into a west facing cliff wall of massive sandstone. The sandstone above the portal was unstable and has required extensive cabling to keep it in place. This will be reevaluated for stability and additional precautionary steps will be taken when mining resumes. Located 420 feet south is the emergency escapeway portal used by Cotter. Underground Operations Underground mining consists of conventional drill -blast stoping using modified room - and- pillar methods. Drifts will be mined approximately nine feet high by eleven feet wide and widened as needed to accommodate mining equipment. Drifts are presumed to be in good condition; not much rehabilitation is anticipated. Rock support will be conventional rock bolting and timbering wherever required. The modified room -and- pillar stoping method will be used to mine the ore, and will commence as soon as rehabilitation of the portal and development to the stoping areas are complete. The room - and - pillar stoping method is similar to the one presently used in the Uravan Mineral Belt, i.e. split - shooting is used in conjunction with leaving rock pillars wherever necessary for roof support. This method of split- shooting involves assessing each face as the stopes advance by the mine geologist, engineer, mine foreman, or experienced lead miner. Since the grades and thickness of the typical Salt Wash uranium - vanadium deposits are highly variable, they are usually unpredictable from one mining round to the next. A round is a complete mining cycle of drill - blast- muck - ground support. A normal round advances a working face about 6 feet. Typically, the thickness of the mineralized material is less than the height needed to advance the stope. As the stope face is being drilled, the blast holes are probed with a Geiger Counter in order to estimate the U3O8 grade. The uranium - vanadium mineralization is usually dark gray to black. The mineralization sometimes rolls, pinches or swells, or follows cross -beds within the sandstone. Therefore, the miner will also use drill cutting color as criteria to help guide blast hole direction and spacing. This irregular habit of the deposit can result in holes collared in mineralized material ending in waste, or, conversely, holes collared in waste may penetrate mineralized material much of their length. Based on the results of the drill -hole assessment, drilled rounds may be loaded and shot in two or more stages. Depending on the location and thickness of the mineralized material in the face (there may be multiple mineralized layers), the miner will attempt to blast either only mineralized material or only waste rock. They will muck the blasted rock out as clean as possible, then shoot the remaining rock and muck it cleanly. The amount of waste rock shot before or after the mineralized material results in typical stope heights of eight -to -nine feet. C -2