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iiiiiiiiiiiiiiiiiii 999 STATE OF COLORADO DIVISION OF MINERALS AND GEOLOGY Department of Natural Resources 1313 Sherman 51., Room 275 ~ Denver, Colorado 80203 I~~~ Phone: 1303) 866-3567 FA%: (303) 832-8106 DEPARTMENT OF NATURAL RESOURCES November 21, 1994 Roy Romer Governor Ms. Kathleen Welt James S. LOChhead Mountain Coal Company Ezeculive Director P.O. Box 591 Michael B. Long Somerset, CO 81434 olvlslon Director RE: Minor Revision No. 1~~; West Elk Mine; Permit No. C-BO-007 Dear Ms. Welt; The Division has reviewed Mountain Coal Company's (MCC) application for a minor revision to replace drawings of MB-2R and MB-3 with as- built designs in Exhibit 66. The following are the Division adequacy concerns regarding the application: MB-2R• 1. Drawing 36-103 has eliminated details on the sediment traps and the weir box. The drawing refers to drawing 36-105 but was not included in the application. Please provide. The size of the pond has not been changed according to the as- built design and the principal and emergency spillways remain at the same elevation; however, the capacity of the pond has increased, sediment storage has increased, detention storage has increased, and the capacity at the primary spillway has increased. Please explain. The SEDCAD model for MB-2R contained in Exhibit 66 does not correspond to the as-built design. The drawing should correspond to the SEDCAD model. MB-3• 1. Drawing 36-102 has eliminated the details on the sediment trap. The drawing refers to drawing 36-105 but was not included in the application. Please provide. The diameter of the principal spillways for MB-3 has been changed from a diameter of 12 inches to 6 inches. In addition, the whole principal spillway design has been changed from the original design. The SEDCAD model should be revised to reflect the as-built principal spillway system. ~,~~ o //-z~ -9