Laserfiche WebLink
<br />agreement (which you have with the Dickersons). Please ensure that the SUP, as long as it is still required to be ta <br />place, is kept current and renewed. Lf, at same point in time, the SUP is no longer required by NPS, or there are <br />changes to it, you must provide written evidence of these changes to DMG. <br />Exhibit S - Geotechnical Stability <br />Your recent submittal included several graphed regressions of highwall stability at various other mines, plus a map <br />depicting a fully mined out site and across-section of the highwalls and benches. No supporting text was included, <br />by the author or by you, and it is not clear what relevance the graphs orcross-section have. The cross-section <br />shows the original 45 degree net slope (though not the revised 41 degree net slope) and a 38 degree slope, but it is <br />not clear ~vhy. Please explain what these figures are intended to convey. <br />You stated that mining would begin on a stage or elevation, and excavation would proceed out from the center <br />toward the perimeter. During extraction, the rock would continually be assessed for its strength and degree of <br />fracture, to ensure that sufficient material remained or that the material surface was adequately stable for final <br />highwalls and benches. Different types of rock and degree of weathering will greatly affect possible final <br />configurations. i will adopt some language from Allen Soreson's recent geotechnical stability memo, as a <br />stipulation regarding Phase II mining and reclamation. <br />At this time, there are no identified geotechnical stability issues regarding Phase I. <br />Other Items <br />Your CDOT notification is adequate. <br />You informed me that the county planning office may impose certain requirements on the proposed operation. If <br />any of these directly involve mining methods or reclamation specifications, either of which might affect your bond <br />amount, please let me know. At this time 1 do not view this as an issue. <br />As before, you must additionally file this letter, and all response materials from you, with the county clerk and <br />recorder. These filings should be made promptly, and receipts for such filings provided to me before the decision <br />date. <br />The decision date is set for January 16, 2001. I must remind you that 1 cannot approve an extension beyond that <br />date, and that if there are still outstanding adequacy issues or the application otherwise does not meet the <br />requirements, it may be denied. <br />When the bond adjustment is to be posted, you should contact Ms. Suzi Ericksen at our Denver office, if you have <br />questions about the types of bonds accepted, or need new bond forms. Her phone number is 303/866-4920. <br />I may be reached at the Division's Durango field office: 701 Camino del Rio, Room 125, Durango, CO 81301; tel <br />970/247-5193 or fax 970/247-5104. i look forward to your responses. <br />Sincerely, <br />~~~~~ <br />Bob Oswald <br />Environmental Protection Specialist <br />faxed copy: Ken Stahlnecker, NPS, Curecanti NRA (970/641-3127) <br />a:ldickerson ado/rco <br />