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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 />June 28, 2010 <br />SAFETY <br />Bill Ritter, Jr. <br />Governor <br />JU Q 1 2090 James B. Martin <br />Executive Director <br />Karmen King DMOon of RzcW7?on, Loretta E. Pineda <br />Grayling LLC IAMtng snd 8?ty Director <br />18050 Rd. G <br />Cortez, CO 81321 <br />Re: Ruby Trust Mine, Permit No. M-1979-181, Amendment AM-1, Technical Adequacy Review Letter. <br />Dear Ms. King, <br />On May 24, 2010, the Division of Reclamation, Mining and Safety formally received the 110(2) Permit Amendment <br />Application AM-1 for the Ruby Trust Mine. The decision date for the amendment application was originally set for June <br />23, 2010 and has now been extended to August 23, 2010. Technical review of the amendment application has revealed <br />numerous items that must still be addressed before it can be considered adequate for approval pursuant to the Hard <br />Rock/Metals Act and Rules. Several of these items have been previously communicated to you and the operator, but <br />since they have not been addressed, are included in this letter. All currently identified issues are included in the list <br />below. Please respond to each of the following items. <br />Exhibit C - Minin Plan lan _(Rule 6.3.3) <br />The application states that the proposed changes will not result in an increase in the amount of waste rock to be <br />generated. There will be a significant amount of waste rock generated, however, and the plan should include better <br />description of where it will be placed on the surface, and the quantities that the waste dump areas can accept. (Please <br />keep in mind that the permit boundary encompasses a 2.3-acre area, of which 0.3 acres are considered "pre-law roads." <br />Inspection reveals that some of these pre-law roads are, in fact, being used as waste rock storage areas, which this office <br />believes should be considered part of the permitted acreage. As such, you must provide supporting information to justify <br />the mining uses of these non-permitted areas, or describe how you will remove the waste rock and refrain from using <br />those areas thus.) <br />The proposed snow shed structure to be built to protect the outside portions of the milling equipment must be sufficiently <br />strong and correctly installed to withstand the potential snowslides that may enter the site at that location. The <br />application does not, however, provide any construction specifications for the materials to be used, the loads or impacts it <br />is to withstand, or how it will be anchored to the cliff. Please provide those items. <br />The underground repository of the sub-grade ore is described as a fairly dry, non-mineralized crosscut, driven on a slight <br />incline (1% slope per Figure C.2). Does it drain or pool at all currently? Does it intersect any identified minor veins or <br />fractures that could affect its stability or future suitability as an ore storage location? Are there veins or workings farther <br />in, beyond the repository segment to be used? <br />The repository will be filled with sub-ore by slurry pipe, which will yield decant water upon placement of the slurry. The <br />plan is to build a bulkhead or coffer dam several hundred feet into the crosscut to capture the water for piping back to the <br />mill. Securely capturing of the water is essential. Please provide better description of the bulkhead and its construction, <br />the liner material to be used and how it is to be emplaced, and the expected mine pool to be impounded (dimensions, <br />volume, possible isolation from the sub-ore, etc.). <br />COLORADO <br />DIVISION O F <br />RECLAMATION <br />MINING <br />Office of Office of <br />Mined Land Reclamation Denver • Grand Junction • Durango Active and Inactive Mines