2011-09-08_REVISION - M1977342 (38)

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f III1IT1iIIJIIiii • CLIMAX MOLYBDEN wrvr W� r,l • A Subsidiary or Phelps Dodge Corporation August 28, 2001 DMG -- Certified Mail No. 7000 0600 0026 1573 5844 Mr. Bruce Humphries Colorado Division of Minerals and Geology 1313 Sherman Street, Room 215 Denver, CO 80203 RE: Topsoil Salvage Methods — Technical Revision TR -1 1 Submittal, Henderson Mill, Permit No. M -77 -342 Dear Mr. Humphries: HENDERSON OPERATIONS 19302 County Road 3 Paraholl, Colorado 80466 (3031 359.3221 Fast (9701 725.0038 RECEIVED SEP 0 It 2001 Division GI Minerals and Geology Climax Molybdenum Company (CMC) would like to propose an alternative method to salvage and stockpile topsoil. Historically, topsoil has been salvaged utilizing a conventional shovel and truck hauling method. Instead, CMC would like to doze and windrow topsoil around our tailing impoundment. Although the topsoil will eventually have to be picked up and moved above the ultimate tailing deposition line, this method allows CMC to salvage the most desirable soil (the top 3 feet) from a greater area. Since other existing topsoil stockpiles will also need to be moved from below the current interceptor ditch, this method also allows us to take advantage of the economies of scale when we move topsoil to its final location CMC received verbal authorization from Mr. Sorenson to try this technique in a 2,000 -foot test area on the northwest end of the tailing pond. The test area was surveyed so that we would have a baseline to measure the results against. We proceeded with the test utilizing our older D -9 and D -8 bulldozers. Upon completion of the experimental method in the test area, CMC surveyed the test area and found that our bulldozers were only capable of moving topsoil to an average depth of 1.2 feet. This was not acceptable, as approximately 3 feet of soil recovery is necessary to meet our reclamation requirements. CMC proceeded by renting a D -I0 bulldozer to re -push the test area with a newer, more powerful piece of equipment. This bulldozer proved to be effective. The test area was again surveyed on August 28` and an average soil cut depth of 3 feet was achieved. Based on the results of this test area, we would like to use this method on a larger scale. CMC will continue to push topsoil around the tailing impoundment until the onset of winter weather forces us to stop. The windrowed topsoil stockpiles will be graded to approximately a 3:1 slope and broadcast seeded for interim stabilization as required. The stockpiles will be marked with signs and surveyed to verify volumes. Stockpile volumes and a map with locations will be submitted with our annual report. Based on the fact that this method will salvage greater quantities of the most desirable topsoil, CMC respectfully requests that the DMG approve this technical revision. A check in the amount of $875 is attached to cover the required application fee.