Engineering & Mining Journal

DEC 2012

Engineering and Mining Journal - Whether the market is copper, gold, nickel, iron ore, lead/zinc, PGM, diamonds or other commodities, E&MJ takes the lead in projecting trends, following development and reporting on the most efficient operating pr

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REGIONAL NEWS - U.S. & CANADA duction is estimated at 5.14 billion lb of copper and 36.4 million lb of molybdenum. The life-of-mine mill feed grade averages 0.31% copper, 0.004% molybdenum, 0.03 g/mt gold, and 0.58 g/mt silver. Project development capital costs are estimated at approximately $1.28 billion, including contingency. With the completion of its positive PEA, Entrée now expects to advance to prefeasibility work at Ann Mason. Future work will include additional drilling, particularly to the north and west of the Ann Mason deposit, to potentially extend the mineralization within the current pit design and reduce the wasteto-mineralization strip ratio. Hecla Readying Lucky Friday for Restart Hecla Mining reported in early November 2012 that it expects to complete rehabilitation of the Silver Shaft at its Lucky Friday mine in the Coeur d'Alene district of northern Idaho by the end of the year, with production expected to resume in the first quarter of 2013. The U.S. Mine Safety and Health Administration ordered the Silver Shaft closed in January 2012 for removal of built-up material in the shaft. The order was pursuant to an investigation that followed a December 14, 2011, rock burst in the mine. The Silver Shaft is a 1-mile deep shaft from surface and the primary access to the Lucky Friday mine. The sand and concrete material being removed from the shaft had built up over a number of years. All other significant activities at the mine, including construction of the No. 4 Shaft and the bypass around the rock burst, were placed on hold. Concurrent with rehabilitation, the Silver Shaft is being upgraded for potential future capacity increases. Hecla also has begun preparations to resume work on the #4 Shaft project in the first quarter of 2013. To date, $90 million has been invested on the estimated $200million project, which is planned to access extensions to reserves and resources and additional exploration targets. The project is expected to be completed in early 2016. Hecla expects Lucky Friday to produce more than 2 million oz of silver during 2013 while it is ramping up to full production. The mine produced 3 million oz in 2011. Hecla also reported that underground drilling continues to extend ore-grade mineralization in four zones at its Greens Creek mine in southeast Alaska, including drill intercepts of 70 ft of 0.3 oz/mt gold, 13.8 oz/mt silver, and 21% combined zinc and 12 E&MJ; • DECEMBER 2012 lead at the 200 South zone and 73 ft of 0.17 oz/mt gold, 17.58 oz/mt silver, and 23.7% combined zinc and lead at the Southwest Bench. In 2013, modeling of these intersections could result in significant additions to the Greens Creek resource. Also at Greens Creek, surface drilling has identified mineralization at Killer Creek 1.5 miles west-northwest of the mine that contains copper-rich veins and bands and at West Gallagher 1 mile west of the mine that contains pyrite mud intervals that have carried anomalous base and precious metal grades in the past. Killer Creek and West Gallagher will be priority targets for Hecla's 2013 summer exploration program at Greens Creek. At Hecla's San Juan Silver project in Creede, Colorado, work is under way on a new, 2,800-ft decline at the historic Bulldog mine. The decline will provide access to a resource of 37 million oz of silver and underground exploration platforms to expand these resources. Support facilities for the project, such as the maintenance and shotcrete shops, have been completed and are operational. Cliffs to Reduce Iron Ore Production Cliffs Natural Resources announced on November 19 that it is delaying portions of its Bloom Lake mine Phase II expansion in Quebec and idling some production at two of its U.S. iron ore operations, Northshore Mining in Minnesota and the Empire mine in Michigan. "These production decreases are driven by increased iron ore pricing volatility and lower North American steelmaking utilization rates," the company said. At Bloom Lake, Cliffs is suspending some components of the Phase II expansion, including completion of the concentrator and load-out facility. Construction related to these activities has stopped, and thirdparty contractors have been demobilized. Pre-stripping activities to develop the working faces of Bloom Lake's orebody, supporting both Phase I and Phase II mine development, are continuing. Cliffs is also continuing its environmental projects related to completing Bloom Lake's water and tailings management system and ore storage facility. Depending on market conditions, Cliffs now expects to complete Bloom Lake Phase II construction in early 2014. The construction delay lowers Cliffs' 2013 estimated eastern Canadian iron ore sales volumes to 9 million to 10 million mt from the previous expectation of 13 million to 14 million mt. Bloom Lake's Phase I facility is expected to produce about 7 million mt during the year. In the United States, effective January 5, 2013, Cliffs will idle two of the four production lines at Northshore Mining. The company will also temporarily idle production at its Empire mine beginning in the second quarter of 2013 in the form of an extended summer shutdown. These production curtailments will impact approximately 125 employees at Northshore and 500 employees at Empire. Cliffs' full-year 2013 expected sales volumes for its U.S. iron ore operations remain unchanged at 19 million to 20 million mt. Cliffs Natural Resources' Northshore Mining operations in Minnesota (shown here), along with its Empire mine in Michigan, are included in the company's plans to reduce iron ore production. www.e-mj.com

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