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Mining Plan resulting slope on each bench was not favorable for revegetation. Since then more growth has • invaded the "slide" area, but it is still very limited. Most interesting though is that subsequent erosion and settling of the "slide" exposed some of the lips of the underlying benches. Meanwhile adjacent benches that were not 1~Iled by the "slide" continued to rapidly decay. The steps of the benches under the "slide" maintained a nearly level configuration. This led to the conclusion that probably it is the exposure of steps to weathering that contributes to their decay. If the steps could he promptly covered and thereby protected from weaithering the decay process could be delayed, although probably not completely controlled or stopped. The procedure of bench reclamation described above will therefore not only create more reclaimable benches but should greatly reduce the rate of decay of the steps. This is accomplished by protecting, as much as possible, the bench from the direct assault by weathering processes. By keeping the step drier and the temperature more uniform through covering with a thick layer of backfill and soil; the rate of the weathering process is greatly reduced. Furthermore, establishing good vegetation on top of the backfilled bench helps reduce water infiltration to the rock surface forming the bench. The vegetation uses much of the moisture that would otherwise seep down to the underlying rock and contribute to bench decay. • Bench decay will probably still occur, but it will occur over a much longer Ume span rather than three or four years as has happened with fully exposed benches in the past. Under this procedure if localized failure of a bench does occur (small pieces rather than a total bench failure which should not occur), the vegetation previously established on the bench will simply follow the small localized slide down to the next bench. Although traumatic to that local area, recovery should occur quickly because all the ingredients (soil, vegetation, seed source, etc.) is atready there to effect the repair by natural means. Furthermore, the visual impact of these small collapses will be 1:o break up the linear pattern produced by the benches. This will have a favorable impact on the visual characteristics of the land. In conclusion, the key to producing highly reclaimable Ltnd in future mining is to alter the process of creating and reclaiming the benches and to pre-design the bench configuration parameters according to an overall model for the entire mountainside. This process can also help alleviate the instability problem that has occurred in the past. In the far distant future it also creates a somewhat more natural appearing hillside. Area MS will be mined using essentially the same techniques used on Area MV. However, because the dip of the rock in this area is about 5 degrees to the east and the mining will proceed along anorth-south line, bench instability factors will not be a problem. • Page 18 Pikeview Quarry Amendment Exhibit D