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office remains skeptical that slopes steeper than 2H:1 V may be successfully revegetated, even with the use of erosion <br />control blanket, geotextile or hydromulch. This office may approve, at this time, the proposed slopes and revegetation <br />methods, but if those sloes cannot be reclaimed adequately within five years after implementation, a revision will be <br />required. These areas will be closely monitored in future inspections. <br />The final gradients specified for the slopes around the pit in the western end of the permit are described as 2H:1 V. The <br />Division believes these are too steep, especially since they are largely comprised of deep backfills of overburden and <br />fines. Though native materials may remain stable at that gradient or steeper, and steep native slopes may support <br />vegetation, 2H: IV is too steep for emplaced materials and seeded surfaces. (Evidence of the difficulty in controlling <br />erosion and establishing vegetation is seen in the slope located north of the present shop building area.) The Division <br />will approve a final slope of 3H: IV or gentler around the pit perimeter. Please comment. <br />Please see other related discussion under "Geotechnical Stability Exhibit" below. <br />Exhibit F - Reclamation Maps (Rule 6.4.6) <br />These are adequate at this time. Areas that will not be disturbed are clearly labeled. However, since no delineation is <br />made to distinguish between disturbed areas that will and will not be revegetated, this office will consider all areas to <br />be revegetated except those areas shown as roads, around private residences, industrial/commercial areas and certain <br />stormwater control structures. Please respond if this assumption is incorrect. <br />Based on the discussion concerning the reclamation slope gradients, above, some of the post-mining contours may not <br />be correctly depicted. However, given the difficulty in reading the contours due to the small scale of the maps, the <br />topography shown may be considered "conceptual" if it is adequately described under Exhibit E. <br />. <br />The Reclamation Maps may need to be modified for certain adequacy responses concerning the Reclamation Plan <br />(Exhibit E) or if the right-of-entry cannot be demonstrated for the BLM-managed lands in Sections 4 and 9. <br />Exhibit N - Proof of Right-of-Entry (Rule 6.4.14) <br />This exhibit is not yet adequate, in that right-of-entry for mining and reclamation activities on BLM-managed lands <br />has not been adequately demonstrated. Evidence for the right-of-entry onto BLM-managed lands in Sections 4 and 9 <br />must be provided by the decision date. <br />Exhibit R - Proof of Filing with County Clerk (Rule 6.4.18) <br />Thank you for the receipt you provided on January 5, 2010 for filing a copy of the last adequacy submittal. Please <br />ensure that you timely file a copy of your next adequacy submittal, and provide a receipt to this office. <br />Geotechnical Stability Exhibit (Rule 6.4.20) <br />This exhibit is not adequate. The maps and notations provided much information, but some of the new material raises <br />new questions. Please address the following: <br />The means of reducing instability of the steep slopes is to be accomplished in various ways, according to the numbered <br />items on Sheets GTSC-2a and 2b. They include riprapping, hydromulching, erosion control blankets, and various <br />geotextiles, among others. It is not entirely clear, however, since some of the items appear redundant and others <br />appear to conflict with others. At this time, we will assume that the list represents the possible range of proposed <br />methods of controlling erosion and sedimentation and stabilizing the slope, without employing redundant or <br />conflicting practices. If additional methods are to be added in the future, a technical revision may be required. <br />In reference to the list of reclamation methods discussed in the paragraph above, Sheet GTSC-2a includes the <br />statement "...the following actions are required unless engineer inspects and determines at the time of backfill that the <br />slope will be stable without some of the tasks." The operator will. be required to provide to the Division a copy of each