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L <br />2.0 GENERAL INFORMATION <br />2.1 PROJECT DESCRIPTION <br />The project area is the Bear Mine No. 3. The mine is located at <br />Somerset, Colorado on the north fork of the Gunnison River. It <br />is an underground "drift" mine with portals located in the "C" <br />seam outcrop approximately 150 feet above the river on a <br />northfacing slope. Mining is accomplished using the room and <br />pillar method and continuous miners. Mining is at this time <br />entirely within the C seam. Bear Mine No. 3 is located at the <br />site of the old Clark Mine, which included workings in both the C <br />seam and the underlying B seam. The C seam at this location dips <br />generally to the north from three to five degrees. However, <br />• actual dip direction may vary locally within the mine from <br />northwest to north-northeast. Overburden thickness will vary <br />from as little as 200 feet near the outcrop to as much as 1500 <br />feet near the east-central portion of the permit area. <br />Development mining utilizes a 49 percent extraction ratio with <br />20-foot wide panel entries located at 70-foot centers, leaving a <br />50-foot by 50-foot pillar. Full extraction is accomplished first <br />by splitting the 50-foot pillars into two 16-foot by 50-foot <br />pillars and slabing first one side and then the other until only <br />small push-out stumps remain. A maxi mum extraction ratio on the <br />order of 90 percent would be anticipated within retreat panels. <br />Extraction ratios of 65 to 70 percent mine wide would be <br />• anticipated at the completion of all retreat mining. <br />3 <br />