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Attachment A <br /> 2.2 Coal Basin is a large topographic feature on the eastern flank of Huntsman Ridge, which <br /> contains two significant perennial streams and associated tributaries, Coal Creek and Dutch Creek. <br /> Coal Basin is approximately twenty-seven square miles in size. Elevations within the Basin vary <br /> between 7,160 to 11,852 feet, with an average elevation of 9,392 feet. Average annual precipitation <br /> is thirty-one inches,predominately occurring as snow fall and summer rains. Principle geologic <br /> units present within the Basin are the Mancos Shale underlying the coal-bearing Mesaverde Group. <br /> The headwaters of Coal and Dutch Creeks are located near the top of Huntsman Ridge at 11,000 feet <br /> elevation. The streams are confluent four miles west of Redstone at an elevation of 8,000 feet. At <br /> Redstone, Coal Creek flows into the Crystal River, which is confluent with the Roaring Fork River, <br /> approximately 17 miles north, near Carbondale. <br /> The Dutch Creek and Coal Creek watersheds'are fairly similar. Coal Creek drains approximately 7.6 <br /> square miles above its confluence with Dutch Creek. Each stream drains an area underlain by <br /> slightly metamorphosed Mancos Shale and Mesaverde Group sediments. However, the 4.1 square <br /> mile Dutch Creek drainage is steeper than the larger Coal Creek drainage. <br /> The average annual flow of Dutch Creek is estimated at 6.1 cfs, while the average annual flow of <br /> Coal Creek, immediately above its confluence with Dutch Creek, is estimated at 8.5 cfs. <br /> Due to geologic and climatologic conditions, each watershed is prone to erosion. Both streams are <br /> visibly turbid during spring runoff and after summer rain storms. Additionally, stream migration is <br /> apparent in response to larger flow events-following summer rains. <br /> 2.3 Please refer to the attached map for the information requested. <br /> 2.4 The Project is designed to address erosion of the mine bench outslopes and the resultant <br /> sediment delivery to Coal and Dutch Creeks. The scope of the Project is sufficient in area to address <br /> the majority of the identified sediment contributing areas which are associated with mine bench <br /> outslopes. The plan to be implemented will compliment reclamation activities already undertaken by <br /> Minerals and Geology. These previous reclamation activities have begun to address the dispersal of <br /> flows from the top of the mine benches, which are a contributing factor to the erosional processes <br /> occurring on the outslopes, and erosion and sedimentation associated with the road network. <br /> The Project is located on public lands administered by the White River National Forest. The <br /> identified uses for the public lands include non-motorized recreation, wildlife habitat and grazing. <br /> Public use of the area is growing as more of the area is reopened. Horseback riding, hiking and <br /> mountain bike riding are the most common recreational uses. <br /> The top of each mine bench outslope is located at an elevation of about 10,000 feet. Commonly the <br /> outslopes are 900 feet in length and reside at the angle of repose. The slopes vary in size from three <br /> tenths of an acre to over eight acres each. These slopes consist of excavated shale and sandstone <br /> materials, commonly intermixed with run-of-mine reject materials. The slopes are generally devoid <br />