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• Gully formation and sediment loss was reduced significantly in postmine drainageways <br />when compared to pre-drainage reconstruction. In Coyote Gulch, for example, an esti- <br />mated 99,400 cubic yards of sediment was lost to gully erosion and sheet and rill erosion <br />from 1984-1987. Following treatment an estimated 1,360 cu yds of sediment is lost <br />annually to sheet, rill and gully erosion. This is a reduction in the annual erosion rate of <br />24 times the pre-treatment erosion rates. Much of the success for the reduction in ero- <br />sion rates must be attributed to the wide variety of erosion control materials, methods <br />and sediment reducing measures that were used in reconstructing drainageways and <br />adjacent reclaimed sideslopes. <br />As a result of appropriate erosion control treatment in re-established postmine <br />drainageways, Trapper Mine has not needed to clean a single sediment pond in two <br />years. A net savings to Trapper Mine of $50,000 has been realized since drainage <br />reconstruction was initiated and sedimentation pond cleaning ceased. <br />3.8 Conclusions <br />As a strategy for soil conservation planning, the promotion of vegetation in combination <br />with natural and/or artificial erosion control measures, has much to offer. Vegetation <br />is one factor that can be easily manipulated by careful management. Beyond that, <br />better vegetative growth, by selecting plants that are well adapted to a particular cli- <br />mate or soil, will almost always provide direct economic benefits in terms of vegetation <br />• production, stability and reduced soil loss. <br />The proper implementation of erosion control materials and sediment reducing mea- <br />sures on reclaimed sideslopes, drainageways, and on regraded spoils are valuable in <br />reducing peak water flows and sediment loads into drainages. Dozer basins are useful <br />to trap and store sediment on newly stripped topsoil areas and on regraded spoils. <br />Livestock water tanks are valuable as they trap water on reclaimed sideslopes, in <br />drainageways, and reduce peak rates of flow at downstream locations, making available <br />reliable water for wildlife and livestock use. Water harvesting diversions constructed <br />across slopes are important to transport excessive water from areas that need protection <br />to sites where water can be used or disposed of safely. Contour farming is essential to <br />reduce sheet and rill erosion on reclaimed sideslope. When combined-with live haul <br />topsoil transport the erosion potential is further reduced. The installation of rock <br />check structure to dissipate the energy of flowing water and trap sediment and debris is <br />valuable in stabilizing channels and promoting vegetation growth. Finally, the use of <br />geotextiles, erosion blankets and other erosion control fabrics are effective in reducing <br />stream velocities and increasing sedimentation in drainageways. <br />The combination of appropriate conservation measures and an aggressive improvement <br />an repair program add up to successful treatment of reconstructed drainage channels <br />and consequently successful reclamation at Trapper Mine while permanent vegetation <br />establishes. <br /> <br />