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STATE OF COLORADO DIVISION OF MINERALS AND GEOLOGY Department of Natural Resources 1313 Sherman St., Room 215 Denver, Colorado 80203 Phone: (303) 866-3567 FAX: (303) 832-8106 Df VISION OF ~~~~~SA MIN&RALS ~('T99 EOLOGY Oj~jsin ,)a/ y RECLAMATION O r//mss MINING•SAPETY October 24, 2003 James Bender Deadwood Gulch Mining Company 5529 US Highway 64 Famungton, NM 87401 Greg E. Walther Executive Director Ronald W. Cattany Aging Division DireQOr b ~ / Re: Incas Mine, Permit M-1986-076, Amendment Application AM-03, Second Adequacy Review Letter. Dear Mr. Bender, I have reviewed your responses to my previous adequacy letter for the above-named application. There are still a few questions that must be answered before the Division's decision is made, which are Listed below. Many of the items in this letter simply state that your responses have adequately addressed the Division's questions. However, where there are still questions, you will see that most of them are minor and will require only brief clarifications, since you provided adequate answers to most of them in your last letter (dated 10/24/03). Decision Date This amendment application is still being reviewed with an extended decision date. Please continue to provide responses until these last items are adequate. As long as the required adequacy responses are provided in a diligent and timely manner, no decision will be made. Published Newspaper Notice You have provided the notarized affidavit from the publisher. This is now adequate, and no further material is needed. Tailinns Disposal Bench You have stated that the tails will be placed against the cut wall, and coned to the depression on the proposed disposal bench. No tails are to be placed on the bench outslope or where the "dam" is (as labeled on the diagrams). The depression to be filled measures 30 feet by 6 feet, more or less, which is an area of 20 square yards. The depression is no deeper than 6 feet (2 yards). The text describes the anticipated volume of tailings to be placed on this bench as I80 tons. It is not clear how this volume of blended tailings can be placed here, and then capped by soil material, leaving a low profile of placed materials. Please clarify these items. (This is one of the situations which could benefit from a cross section diagram.) Tailings Material to be Blended Your response states that you are committing to make your tailings conform to the conditions previously set forth in the file, as part of AM-02. No further information is needed. Permeability of Cap Above Tailings Your response stated that the cap to be placed over the tailings would have a permeability of 106 cm/sec (centimeters per second), though this rate is even higher than the incorrect figure of 10 cm/sec contained in your initial submittal. The new response is incorrect, in that it also appears to contain a typographical error. The existing File contains an approved maximum rate of permeability, which is 10-6 cm/sec or less, as is stated in a 1995 O1~i00`ajJOO~Cepj~r GolveOmor s