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V. Sediment and Erosion Control <br />Reclamation of the Coal Basin Mine has succeeded in reducing sediment contribution from mining <br />related disturbances to Coal and Dutch Creeks. The thirteen mile long mine haul road system and <br />the long steep slopes below the mine entry areas were the principle contributors of sediment to <br />Coal and Dutch Creeks during mining operations. Reclamation work has stabilized the un- reclaimed <br />portions of the mine site, and has reduced sediment contribution to Coal and Dutch Creeks to an <br />acceptable rate which does not affect the post- mining land -use of rangeland or that negatively <br />affects the environment. <br />Road System Reclamation <br />Reclamation of the road system was designed so that erosion potential from the road surface and <br />from the fill slopes located immediately below the roads was minimized. During reclamation <br />construction, all of the culverts along the haul roads were removed, the road surfaces were graded <br />to minimize the distance and velocity of overland surface water flows, and fill slope lengths were <br />reduced. Numerous water carrying dips were created to move drainage from the cut to fill sides of <br />the reclaimed road network without allowing for a great accumulation of water. The road surfaces <br />were severely ripped and then seeded. The result of these activities is a roughened, well vegetated <br />surface suitable for hiking, horseback riding and in some cases, mountain bike riding. Erosion and <br />sedimentation from the road system is now negligible. Rilling and gullying has been minimized to <br />the extent possible at the reclaimed portions of the Coal Basin Mine. <br />Mine Bench Outslope Stabilization <br />The mine bench outslopes are long, steep unconsolidated fill slopes that extend from the mine <br />entry areas down adjacent steep slopes toward nearby drainages. Many are uninterrupted slopes, <br />while two are traversed by the former haul road network. Seven mine bench outslope features <br />existed at Coal Basin. Stabilization work at these locations involved diversion and dispersion of up- <br />slope water that contributed to the erosion problem, and attempted establishment of a vegetative <br />cover at or near the base of the individual outslopes. <br />Diversion and dispersion of the up -slope water played a significant role in stabilizing the slopes. <br />Additionally, four of the outslopes have been successfully stabilized by establishment of a <br />vegetative cover. Sediment from a fifth slope is trapped at the base of the outslope by vegetation <br />established during reclamation efforts. Sediment from the two remaining slopes is partially <br />retained by vegetation established at the base of these slopes. These slopes are extremely difficult <br />areas on which to establish vegetation as a result of the severe slope angles and lack of any soil <br />11 <br />