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Section 2.05.6 Sediment Disposal Plan • During the bonding period, Sun Coal Company will maintain sediment storage pond and trap capacity in accordance with the criteria presented in the mine permit application. Sun Coal Company will excavate approximately 75 cubic yards per year, or approximately 750 cubic yards during the bonding period. Sun Coal Company, in accordance with the approved disposal plan, will place the material in approved disposal sites. When sediment structure cleanout is required, Sun Coal Company will dis- pose sediment in one of two authorized sediment disposal areas (Map 8). Area 1 (Yampa River) is located immediately east of Culvert ql between the culvert invert and the crusher. Area 2 is located adjacent to the reclaimed mine area on a small bench located in the SE SE of Section 23, Township 6 North, Range 87 West (dragline erection site). The estimated storage volume for Areas 1 and 2 are approximately 1,500 cubic yards each. The storage volume estimates are based on the storage areas being approxi- mately 200 feet long, ten feet high and having 4:1 outslope. Based on existing maintenance and sediment disposal activities, either site will be capable of containing and disposing all anticipated sediment volumes. The material will be removed using a backhoe/front end loader/end dump truck and/or scraper and will be transported to the sediment disposal areas. Prior to end dumping the material, a small berm (one foot high with 3:1 side slopes) will be constructed around the disposal area. The berm will create a small containment area which will ensure wet sediment and/or surface water run-off will be contained during disposal activities. After the berm is constructed, transported sediment will be end dumped into the disposal area and spread out to facilitate drying. When the material is dried, the material will be graded and compacted in lifts not exceeding twelve inches. While the disposal area is being created, the material will be periodically shaped to conform to the existing topography and will be fertilized, mulched and seeded in accordance with the criteria outlined in the revegetation plan (Bench Seed Mix - Table 2.05.4-2). The designated disposal areas will be graded to a 4:1 slope unless otherxise approved by the Division. The final slope will be graded to provide a margin of safety to ensure the material will be geotechnically stable to support the post-mine land use. The excavated material will not be disposed in designated areas where the height will exceed ten feet or where the necessary precautions have not been taken to minimize erosion and off-site sedimentation impacts. Upon final disposition of the disposal areas, and prior to final bond release, the disposal areas will be revegetated in accordance with existing recla- mation procedures. If deemed necessary, geotechnical stability analysis will be conducted, as necessary, in order to obtain the CMLRD performance stability factor of 1.3. If a stability factor of 1.3 is not achieved, Sun Coal Company will take necessary remedial measures to achieve the desired stability safety factor. 379-A (Rev. 12/86)