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_~ ~II II~~I~~I~~~~~ ~I~ //~' Cripple Creek & Victor Gold Mining Company 999 l\ ~ A Joint Venture -Pikes Paak Mining Company, Manager ~~(~//~ 7 Operations Offlce Englewood Office lt~7TLV P.O. Box 191, 2755 State Highway 67 5251 DTC Parkway, Suite 700, Englewood Victor, Colorado 80860 Colorado 80111 (719) 689-2977 • FAX (719) 689-3254 (303) 889-0700 • FAX (303) 869-0707 December 15, 1994 SENT BY FACSIMILE -HARD COPY FOLLOWS BY MAIL Mr. Berhan Keffelew Environmental Protection Specialist Colorado Department of Natural Resources Division of Mines and Geology Office of Mined Land Reclamation 1313 Sherman Street, Room 215 Denver, Colorado 80203 ~FCEI~ED DEC 2 0 1994 nv~sion u~ w~lnerals is Ueology Reference: Cresson Project; Permit M-80-244: Specification Change For Select Drain Cover Fill and Condition on OMLR Approval. Dear Mr. Keffelew: The Cripple Creek & Victor Gold Mining Company ("CC&V") has reviewed your approval letter of December 13, 1994 concerning Select Drain Cover Fill and appreciates the Office's expeditious approval. However, your letter makes reference to 12 percent passing the number 40 sieve and then requires posting of a bond to flush the riser pipes or drill injection wells. As I stated to you earlier, CC&V does not believe there is any reason to be concerned about plugging of the risers pipes in terms of ensuring their availability for detoxification. First, there is a 5 percent limit on the amount passing the ry 40 sieve. Second, the amount of fines in the material remains minimal and will be flushed out of the system in the very early stages of operation. As you know, the amount of Select Drain Cover fill is small. It is our experience that these "fines" do not continue to migrate out of this Select Drain Cover fill over time but are flushed in the first weeks of operation. If, in fact, there were plugging problems, they would be noted very early during operations and the need to circulate pregnant solution would necessitate remediation in the early stages of the Project. Further, given the relatively coarse nature of the surrounding ore which is confirmed by the lack of need to agglomerate the fines, we have no reason to expect a buildup of fines in the sump area over time. CC&V will make available to you the information it gathers as circulation operations start and are lined out and will record and report to you any measured plugging during that period. Should plugging be observed and that plugging is judged to adversely affect the circulation, CC&V will commit to submitting a mitigation plan to the Office. This issue has been reviewed by CC&V and by Golder Associates, Inc. and all who have been consulted believe, based on their experience, that the slight increase in fines will not create any plugging of the risers.