2011-10-25_PERMIT FILE - P2011030

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There will be up to 46 core holes, all drilled from 21 drill pads in upland locations. As core drilling goes, cuttings are usually minimized. During reclamation, will cuttings be scattered, buried, or replaced in the drill holes before closure? This may affect the bond amount. What is to be done with all of the cores, particularly the non - mineralized (non -vein) sections? For example, will they be removed from the drill site or buried at the site? This may affect the bond amount. The depth of the upland drill holes will vary from 250 feet to 800 feet. The file reflects that past drill holes have all been dry. Based on the map, it does not appear likely that the proposed drill holes will intercept existing mine workings (which could provide a conduit for potential groundwater) and the Division accepts that the drill holes will be dry. As such, the proposed drill hole closure (near - surface plugging) seems adequate. Please be advised that if groundwater is encountered, that full -depth bore hole sealing will be required. For now, only surface plugging costs will be included in the bond amount. The Revenue Mine has an existing discharge which reports to the pond near the portal via existing pipeline. The NOI estimates that the total discharge is 200 gallons per minute, a small fraction of which originates on the Yellow Rose vein where the rehab and extension are planned to occur. There are no recent water quality reports in the NOI materials, though a 1983 report was provided. Current water data will be required before this office can approve any activity that could impact the hydrologic balance. The surface drilling from the upland drill sites and the tunnel rehab work are not expected to have a hydrologic impact. However, before extension on the Yellow Rose vein may commence, this office must receive sufficient water quality analyses from current sampling. (Note: It is generally required to provide five consecutive quarters of data prior to commencing activities.) This agency cannot approve a project that will adversely affect the water quality or that might require perpetual water treatment. It is known that this reach of Sneffels Creek has been affected by past mining activity, but it is nevertheless essential to establish a baseline for this project. Please try to sample the water and provide analyses of the creek upstream and downstream of the mine, and of the water at the portal, before winter if possible. Please describe the sampling to be undertaken for this project. A financial warranty (a bond) has been provided, though there are still technical issues to address that may affect the required bond amount, and the Division has not calculated the bond. Please note that until the required bond amount is calculated, and the bond is provided to and accepted by the Division, no prospecting activity may commence. Due to the complexity of this NOI, the Division has extended its review period by up to 60 days. The decision date has been reset to December 29, 2011. Please respond to the questions above, by providing two sets of all materials. These may be sent directly to me at the Division's Durango Field Office: 691 CR 233, Room A -2, Durango, CO 81301; telephone 970 - 247 -5193. Sincerely, Bo1; Oswald Environmental Protection Specialist Cc: Greg Lewicki, Greg Lewicki and Associates, 11541 Warrington Ct., Parker, CO 80138 Ec: Steve Shuey, DRMS Grand Junction (c: \11 -10 docs\Revenue NOI par2 /rco)