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Award Nomination for Excellence in Surface Coal Mining and Reclamation - USDI, OSMRE - 1990 September, 1990 Dozer basins (sediment basins) were constructed to trap and store sediment on newly stripped topsoil areas and on regraded spoils to reduce or abate the sediment load. Basins are used [o prevent the siltation of diversions, waterways, livestock ponds, and streams; to trap sediment originating from the active mine site and [o prevent undesirable deposition on undisturbed bot[omlands and reclaimed areas. Livestock watering tanks (ponds) are used to trap water on reclaimed sideslopes, in drainageways, and to reduce peak flows at downstream locations making available reliable water for wildlife use. The location of livestock ponds is such that a minimal amount of sediment will be deposited. This was accomplished by installation of ponds at headwater locations or on relatively gentle grades often within water harvesting diversions on reclaimed sideslopes. Water harvesting diversions are channels constructed across slopes with a supporting ridge on the lower side that is used to transport excess water from areas that need protection to sites where water can be aced or disposed of safely. A diversion's effectiveness as a sediment reducing measure is in diverting the runoff which would otherwise flow across erosion susceptible areas, thus detaching and transporting soil particles. Contour farming and live haul topsoil transport are used on all reclaimed sideslopes and drainage areas when possible. Topsoil replacement, seedbed preparation, and planting are done on the contour. Con- touring can reduce erosion by 40 to 50 percent. When contour farming is combined with live material topsoil transport the erosion loss potential can be further reduced. Contouring provides excellent erosion control by reducing transport from moderate rainfall events. Rock check structures are used to dissipate the energy of (lowing water within the drainageway channel. Debris and sediment tend to be deposited and trapped upstream of structures. This in turn permits establishment of vegetation behind structures which further stabilize the channel. In addition, filter fabric is installed and used to line rock check structure core trenches, thus providing additional structural sup- port and reduces the potential for advancement of downstream headcutting to move upstream. Cover crops and mulch are used very effectively in drainageways to reduce the detachment of soil by rain- fall and runoff while providing seasonal protection and soil improvement. Cover crops provide protection from wind and water erosion during vegetation establishment periods when permanent vegetation is inadequate to provide adequate cover. Permanent vegetative (grasses, forbs and shrubs) cover provides the most significant and permanent long term solution to erosion control problems. The selection of species adapted to the climate and soils is one of the most important steps in achieving success. Woody plants are desirable for the long term sta- bility of aparticular site. However, woody plants require time to develop sufficient size to control erosion adequately and the quick cover that can be obtained with grasses and forbs is needed in the interim. Willow wattles and woody seedling transplants are installed in drainageways and serve as energy dissi- paters for water and soil moving down the drainageway and provide long term stability. Woody plants filter and trap entrained debris (soil, small rocks, veg litter) and provide a series of areas with reduced slope angles on which vegetation can be established. Deep rooted woody vegetation prevents gully forma- tion and will become part of the permanent stabilizing cover. Brush matting (crimping) is essentially a deep mulch of hardwood brush and soil crimped into existing drainage cuts. The technique is employed very effectively in damaged stream channels and on stream banks to protect against accelerated erosion rates when a channel needs repair. Erosion control fabrics, matting, fibers, strands and soil confinement systems are used effectively in reducing stream velocities and increasing sedimentation in reconstructed drainage channels. Various combinations o[ materials are used to solve erosion problems on a site specific basis.