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• Gutty formation and sediment loss was significantly reduced in postmine draiaageways when compared to <br />pre6rainage reconstruction. In Coyote Gulch, for example, an estimated 99,400 cubic yards of sediment <br />was lost to gully erosion and sheet and rill erosion from 1984-1987. Following treatment an estimated 1,360 <br />cu yds of sediment is lost annually to sheet, rill and gully erosion. This is a reduction in the annual erosion <br />rate of 24 times the pre-veatment erosion rates. Much of the success for the reduction in erosion rates must <br />be attributed to rite wide variety of erosion control materials, methods and sediment reducing measures that <br />were used in reconstructing dtainageways and adjacent reclaimed sideslopes. <br />As a result of appropriate erosion control treatment in reestablished postmine drainageways, Trapper Mine <br />has not needed to clean a single sediment pond in five years. <br />3.8 Condusionv <br />As a strategy for soil conservation planning, the promotion of vegetation in combination with natwal and/or <br />artificial erosion control measures, has much to offer. Vegetation is one factor that can be easily manipu- <br />lated by careful management Beyond that, better vegetative growth, by selecting plants that are well <br />adapted to a particular climate or soil, will almost always provide direct economic benefits in terms of <br />vegetation production, stability and reduced soil loss. <br />The proper implementation of erosion control materials and sediment reducing measures on reclaimed <br />sideslopes, drainageways, and on regraded spoils are valuable in reducing peak water flows and sediment <br />loads into drainages. Dozer basins are useful to vap and store sediment on newly stripped topsoil areas anti <br />on regraded spoils. Livestock water tanks are valuable as they vap water on reclaimed sideslopes, in <br />• drainageways, and reduce peak rates of flow at downstream locations, making available reliable water for <br />wildlife and livestock use. Water harvesting diversions constructed aaoss slopes are important to transport <br />excessive water from areas [hat need protection to sites where water can be used or disposed of safety. Con- <br />tour farming is essential to reduce sheet and rill erosion on reclaimed sideslope. When combined with live <br />haul topsoil transport the erosion potential is further reduced. The installation of rock check swctures to <br />dissipate the energy of flowing water and vap sediment and debris is valuable in stabilizing channels and <br />promoting vegetation growth. Finally, the use of geotextiles, erosion blankets and other erosion control <br />fabrics are effective in reducing sveam velocities and increasing sedimentation in drainageways. <br />The combination of appropriate conservation measures and an aggressive repay program add up to success- <br />ful treatment of reconstructed drainage channels and consequently successful reclamation at Trapper Mine <br />while permanent vegetation establishes. <br />Perhaps the major problem with such a soil conservation strategy is that it requtres continuous, sensitive, <br />timely and knowledgeable management of the soil and vegetation and the use of appropriate and cost effec- <br />tive erosion control techniques and material to be fully effective. But Ute rewards in terms of reduced soil <br />loss and potential dollar savings are indisputable. <br />3.9 Referwces <br />Dnt, R.L. 1961..4n application of the pointeentered quarter method to the sampling of grassland vegeta- <br />tion. J. Range Manage. 14:6369. <br />Viert, S.R. 1985. A new instrument far measuring ground cover based on [he point-hit technique - [Ile opti- <br />cal point bar. p. 106-109. In: 1985 Annual Meeting of the Amer. Soc. for Surface Mining and Reclamation. <br />• Oct 8-10, 1985. Denver, CO. <br />NyfJ)6 3193 <br />[CO[v11.R\92REPT3] <br />