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• Contour farming and live haul topsoil transport are used on all reclaimed sideslopes and drainage areas <br />when possible. Topsoil replacement, seedbed preparation, and planting are done on the oontour. Con- <br />touring can reduce erosion by 40 to 50 percent When contour farming is combined with live material top- <br />soil transport the erosion loss potential can be further reduced. Contouring provides excellent erosion con- <br />trol by reducing transport from moderate rainfall events. Contouring in combination with diversion estab- <br />lishment can be very effective in reducing erosion potential <br />Rock check structures are used to dissipate the energy of flowing water within the drainages channel <br />Debris and sediment tend to be deposited and trapped upstream of structures. This is turn permits estab- <br />lishment of vegetation behind swctures which further stabilize the channel In addition, filter fabric is <br />installed and used to line rock check structure core trenches, thus providing additional structural support <br />and reduces the potential for advancement of downstream headcutting to move upstream. <br />Cover crops and mulch are used very effectively in drainageways to reduce the detachment of soil by rainfall <br />and runoff while providing seasonal protection and soil improvement Cover crops provide protection from <br />wind and water erosion during vegetation establishment periods when permanent vegetation is inadequate <br />to provide adequate cover. <br />Permanent vegetative (grasses, forbs and shrubs) cover provides the most significant and permanent long <br />term solution to erosion control problems. The selection of species adapted to the climate and soils is one <br />of the most important steps in achieving success. Woody plants are desirable for the long term stability of a <br />particular site. However, woody plants require time to develop sufficient size to control erosion adequately <br />• and the quick cover that can be obtained with grasses and forbs is needed in the interim. The principles for <br />selection of herbaceous vegetation is based on a particular species adaptation to the mine site and its ero- <br />sion convol potential The ideal species have strong root development A diverse mixture of plant species <br />increases [he assurance of a stand as it is difficult to anticipate all of the variables that will affect germination <br />and stand establishment on any given site. <br />Willow wattles and woody seedling Vansplants are installed fn drainageways and serve as energy dissipaters <br />for water and soil moving down the drainages and provide long term stability. Woody plants filter and trap <br />entrained debris (soil, small rocks, veg litter) and provide a series of areas with reduced slope angles on <br />which vegetation can be established. Deep rooted woody vegetation prevents gully formation and will <br />become part of the permanent stabilizing cover. <br />Btvsh matting (crimping) is essentially a mulch of hardwood brush crimped into existing drainage cuts. The <br />technique is employed very effectively in stream channels and on stream banks to protect against acceler- <br />ated erosion rates when a channel needs repay. <br />Erosion control fabrics, mattings, fibers, strands and soil confinement systems are used effectively in reduo- <br />ing stream velocities and increasing sedimentation in reconstructed drainage channels. Various combina- <br />tions ofmaterials are used to solve erosion problems on a site specific basis. <br />Erosion control fabrics provide a ground armor [hat dissipates the energy generated by water movement <br />from run-0ff or rainfall Soil retention is a secondary function. Fabrics offering high strength and abrasion <br />resistance are used under rip rap. <br />• <br />