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Section E.3 Reclamation Implementation Section E.3.1 Mine Pits Section E.3.1.1 East Pit b5. Persuant to Minerals Rules and Regulations Number 6.1, Grading shall be carried on so as to create a final topography appropriate to the final land use selected in the reclamation plan. The proposed final configuration of the east pit, i.e., 75 ft. benches with highwalls 50 ft. in height and 90 ft. slope lengths, approaching 1.5H:1V, is not appropriate to the final land use designated as rangeland and wildlife habitat. Slopes steeper than approximately 4H:1V become exceedingly difficult to establish vegetation, inhibit livestock utilization (Stoddard, Smith, and Box, 1975), and are more susceptible to erosion and resulting sedimentation of drainages. Reclamation of the proposed final configurations of the east pit is further hampered by the south-facing slope-aspect and coarse texured, erodible, sub- and topsoils available for replacement, both conditions known for moisture defi:iencies and adverse impacts upon vegetation establishment and maintained growth. Cook, Hyde, and Sims, 1974, specify that in Sagebrush Foothill Vegetation Types, "all south and west-facing slopes should not be steeper than four to one, and five to one, where possible. North-facing slopes should not be steeper than three to one." Cook, et.al., further specified that in Foothill Juniper Vegetation Types, "If possiblle all south and west-facing slopes should not be more than four to one and north and east-facing slopes not more than three to one." Approval of the Earth Resources, Inc. 1983 amendment was recommended by the staff following agreement with the operator that the final pit slope configurations would range from 1.25 to 4 horizontal to 1 vertical, and that any slopes greater than 30 degrees, or 1.75H:1V would be broken with a series of terraces. It is recommended that the east pit be filled to capacity with the waste rock generated from the west pit, and the final topographic configfurations approach that of the pre-mining contours. Please discuss. Section E.3.1.2 West Pit 66. The narrative explains that "no additional grading of the pit is planned as part of the reclamation. The wide benches and exposed cliff areas will provide habitat fora wide variety of birds and other wildlife." Please indicate how terrestrial animals will ingress and egress form the pit area as the perimeter is composed of a series of 15 ft. highwalls and benches, in some cases whoses cummulative depths exceed 350 feet. 67. Please provide a perimeter safety bench measuring approximately 3 ft. high by approximaely 20 feet wide to minimize the impact of possible human, wildlife, or domestic livestock accidental falls.