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7. Erosive power of stream channels has not been significantly <br />• changed by mining and reclamation except for specific areas <br />where stream channel gradient has increased. <br />8. Existing channel slopes, velocities, and values of shear stress <br />are not significantly different from approved channel slopes. <br />9. The majority of the existing and approved channels are stable <br />for the 10-year, 24-hour storm event, assuming a 12 foot channel <br />width. <br />10. Vegetation is important in maintaining long term stability. <br />11. To improve channel stability for the design storm, structural or <br />• nonstructural mitigation measures are necessary to reduce the <br />slope and decrease the erosive velocity. <br />Quantitative landfarm analysis at the Colorado Yampa Coal Company, <br />Eckman Park Mine demonstrates that the existing topography does not <br />differ significantly from the approved postmining topography. Also, <br />existing stream Channel erosive power does not differ significantly from <br />the approved condition. However, several isolated locations have been <br />identified which may prove difficult to stabilize with vegetation alone. <br />These sites can be treated with one or more erosion control alternatives <br />which will mitigate the potential for excess erosion. <br /> <br />40 <br />