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9. Conclusions <br />Section 6 of this report establishes the fact that backfilling to <br />original contour is not stable for a wide range of fill types. <br />Over and above the engineering analysis of the slope stability, a <br />critical question to ask is whether or not any real good is <br />accomplished by backfilling to approximate original contour. <br />Various topics are discussed below related to this question. <br />1) Avalanche Paths - As discussed in Section 7, the environmental <br />damage from avalanches would increase if original contour was <br />restored. <br />2) Erosion - By attempting to redisturb the fill slopes of <br />approximately 15 miles of roads, which have been in place for over <br />30 years, a very significant increase in erosion would be seen for <br />a number of years after the work is done. Also, it would be very <br />d i f f i c u l t to control erosion on the backf i l l ed slopes at such steep <br />angles. <br />3) Vegetation - Considerable past experience of reclaiming steep <br />slopes in Colorado has shown that it is extremely difficult to <br />vegetate a slope of 45 degrees, especially when no topsoil is <br />reasonably available to cover the material. The proposed <br />reclamation alternatives of Section 8 will be much easier to <br />vegetate since the surfaces are relatively flat. <br />4) Post - Mining Land Use - Since the road areas are only 35 to 65 <br />feet wide, a revegetated flat area in grasses would likely be <br />heavily used by wildlife. Game animals tend to graze more readily <br />if the protection of the forest is not far away. The flat <br />revegetated road areas would be a better asset for wildlife than <br />the steep, unstable slopes with less vegetation. <br />5) Downhill Slope Stability - Many remaining fill slopes below the <br />road would be in serious threat of failure if original drainage <br />patterns were to be restored, as described in Section 4. Many of <br />the fill slopes simply cannot handle additional water from the <br />slopes above. <br />In addition to the above - mentioned problems, it is extremely <br />doubtful that it is even physically possible to bring the material <br />up from the steep fill slopes below to restore the original <br />contour. I n some areas, the existing road f i l l slope extends 300 to <br />21 <br />