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<br />STATE OF COLORADO <br />DIVISION OF RECLAMATION, MINING AND SAFETY <br />Department of Natural Resources <br />1313 Sherman St., Room 215 <br />Denver, Colorado 80203 <br />Phone: (303) 866-3567 <br />FAX: (303) 832-8106 <br />January 28, 2008 <br />Mr. Ross Gubka, P.E. <br />Chief Engineer <br />Western Fuels-Colorado <br />P.O. Box 628 <br />Nucla, Colorado 81424 <br />NJ <br />Re: New Horizon Mine, Permit No. C-81-008 <br />Technical Revision No. 56 (TR-56) Adequacy Review <br />Dear Mr. Gubka: <br />COLORADO <br />D I V I S ION OF <br />RECLAMATION <br />MINING <br />- ?t- <br />SAFETY <br />Bill Ritter, Jr. <br />Governor <br />Harris D. Sherman <br />Executive Director <br />Ronald W. Cattany <br />Dlvision Director <br />Natural Resource Trustee <br />The Colorado Division of Reclamation, Mining and Safety (Division) has reviewed <br />Western Fuels-Colorado (WFC's) TR-56 application submitted for incorporating the As- <br />Built Certifications for Sediment Ponds 011 and 013 into the permit document. Some <br />significant changes were noted between the approved designs and the As-Built <br />information submitted with TR-56 regarding the principal and emergency spillway <br />configurations and size of each impoundment. These differences were also identified <br />during our recent inspection of the site following construction of Ponds 011 and 013 (see <br />inspection report dated December 14, 2007). A brief discussion of the design and <br />construction of each pond is given below followed by the Division's adequacy review <br />comments. <br />Pond 011 <br />Pond 011 design was approved by the Division with TR-54 in 2007. The design was for <br />a riser pipe for the principal spillway with a 4-inch weep hole below the spillway <br />elevation. A valve was incorporated into the design, but was to remain shut as shown on <br />approved Map 2.05.3(3)-14 and played no significant role in the treatment capacity or <br />operation of the pond. <br />Pond 011 was constructed significantly different from the approved design. As stated in <br />our inspection report, instead of (1) 4" weep hole as designed, the principal spillway as <br />constructed has two (2) six" adjustable valves below the principal spillway discharge <br />elevation. There were also changes to the design and location of the emergency spillway. <br />From the As-Built information submitted with TR-56 it is unclear how the pond will be <br />operated. There are also inconsistencies with the information presented in the As-Built. <br />Office of Office of <br />Mined Land Reclamation Denver • Grand Junction • Durango Active and Inactive Mines