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<br />backfilling this highwall to a 3H:1 V r~r~. Since the highwall is currently advanced to the <br />permit boundary and the site currently has an estimated 47,500 cubic yard shortage of backfill <br />material, the backfill task included ripping of five acres of pit floor to supply the backfill <br />material and dozer pushing the material into place from the bottom to the top. If these <br />assumptions are incorrect, please clarify the discrepancy in your adequacy response. <br />2. The TR-001 drawings also indicate a 250 footJong by 60 foot high section of the north <br />highwall. The approved mining plan specifies that this highwall will be mined at a 3H:1 V <br />grade. Therefore, mining of this highwall to a vertical grade and then backfilling it is not in <br />compliance with the approved mining and reclamation plans. Please revise these plans to <br />detail these changes. <br />C and J has indicated that excavation of the north highwall is completed. :'herefore, DMG has <br />calculated the enclosed reclamation cost estimate to include full backfill of a highwall of this <br />dimension using in-place overburden at the crest of the highwall and material in the stockpile <br />at the northwest corner of the site. If these assumptions are incorrect, please clarify the <br />discrepancy in your adequacy response. <br />3. Backfilling of the pit in the pit floor has been calculated using a combination of cut and fill and <br />stockpile backfilling from the southwest stockpile. If this assumption is incorrect, please clarify <br />the discrepancy in your adequacy response. <br />The enclosed estimate shows a substantial increase in the required financial warranty for the <br />Montoya Pit. Barring any significant changes to the assumptions made above for the mining and <br />reclamation plans, a financial warranty in the amount shown will be due sixty days from the <br />approval date of this revision. However, C and J can reduce the amount required by completing <br />as much of the reclamation as possible prior to the sixty day due date and requesting an <br />inspection of the reclamation work performed. <br />BLM indicated that another ten acre lease block may be awarded to C and J in the near future. If <br />this occurs and C and J specify, in this revision, that in this scenario they will immediately reduce <br />the west highwall to a 2H:1 V slope and continue excavating that slope at a 2H:1 V, reclaiming it <br />to a 3H:1 V slope using overburden from the new lease block, then upon awarc{,of that lease <br />block, DMG can revise the reclamation cost estimate accordingly. <br />If you need additional information, please contact me at the Division of Minerals and Geology, <br />Durango Field Office, 701 Camino Del Rio, Room 125, Durango, Colorado 81301, telephone no. <br />970-247-5062. <br />Sincerely, <br />Steve S. Shuey <br />Environmental Prot tion Specialist <br />