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8 E&MJ; • MARCH 2014 www.e-mj.com REGIONAL NEWS - U.S. & CANADA Detour Gold Updates Detour Lake Life-of-Mine Plan Detour Gold has announced an updated life-of-mine plan for its 100% owned Detour Lake open-pit mine in northeastern Ontario. The mine poured its first gold in February 2013 and reached commercial production in September 2013. Pro- duction during 2013 totaled 232,287 oz of gold, and production during 2014 is forecast at between 450,000 and 500,000 oz of gold at an estimated total cash cost of $800 to $900/oz of gold sold. The new Detour Lake mine production plan supports a 21.7-year operating life from current mineral reserves standing at 15.5 million oz of gold in 476 million metric tons (mt) grading 1.02 g/mt gold. Mill throughput is planned to increase from 55,000 mt/d currently to 61,000 mt/d in 2017. Life-of-mine average annual gold production is forecast at approximately 660,000 oz/y at total cash costs of C$723/oz sold. Five-year average annual gold production is forecast at approximately 600,000 oz/y at total cash costs of C$759/oz sold. Detour Lake mining rates are expect- ed to average 252,000 mt/d in 2014 and increase to a peak of 389,000 mt/d in 2020. The haulage truck fleet is project- ed to increase from the current 23 trucks to 41 trucks at the peak of the mine operation from 2026 to 2031, with no additional shovels beyond the current two electric rope shovels and three hydraulic shovels. The mining fleet will be support- ed by two smaller shovel/excavators. Detour Gold continues to stockpile material grading between 0.4 and 0.5 g/mt gold, estimated at 107.3 million mt averaging 0.45 g/mt gold over the life of the mine. This 'mineralized waste' is not included in the mineral resources or in the current mine plan. It could potentially be processed at the end of the mine life, depending on the gold price environment. Regarding the new Detour Lake life-of- mine plan, Detour Gold COO Pierre Beaudoin said, "The mine plan reflects our operating experience gained during the past two years in pioneering the pit and, over the past year, operating the process plant. The mine plan optimizes the first five years, while addressing our operational risks." Silver Standard Buying Marigold Mine from Goldcorp, Barrick Silver Standard Resources agreed in early February to purchase the Marigold gold mine in northern Nevada from sub- sidiaries of Goldcorp and Barrick Gold for $275 million in cash. Goldcorp is 66.7% owner and operator of the mine; Barrick holds the remaining 33.3%. The transac- tion is expected to close in April. The Marigold mine is an open-pit, heap leach operation at the northern end of the Battle Mountain-Eureka trend in Humboldt County, Nevada. The mine pro- duced 162,000 oz of gold in 2013 and is expected to produce between 142,000 and 150,000 oz in 2014. Silver Standard Resources is head- quartered in Vancouver, British Columbia. Upon closing of the Marigold transaction, it will become a two-mine company. It currently owns and operates the Pirquitas silver-zinc mine in Jujuy province, north- ern Argentina, which produced 8.2 mil- lion oz of silver and 27 million lb of zinc in 2013. The company also has two wholly owned, feasibility-stage projects, Pitarrilla in Mexico and San Luis in Peru. Commenting on the Marigold purchase, Silver Standard President and CEO John Smith said, "This acquisition accomplish- es our strategic goal of adding an operat- ing mine in a well-established, low-risk mining jurisdiction. We retain our financial capacity to continue internal growth and expect improved corporate operating cash flow going forward as a result of our 2013 cost-restructuring program and the addi- tion of the Marigold mine." The Marigold mine has been in contin- uous production since 1988. Ore is mined by conventional truck-and-shovel equip- ment and processed via a 40,000-mt/d, run-of-mine heap leach operation. The mine has consistently produced more than 140,000 oz/y at gold recoveries in excess of 70%. In 2012 and 2013, Goldcorp and Barrick invested more than $150 million to purchase new, larger mining equip- ment, which is expected to improve the efficiency of future mining operations. As of year-end 2012, proven and prob- able Marigold mineral reserves totaled 294.5 million mt, grading 0.52 g/mt gold and containing 4.92 million oz of gold. The mine currently employs 360 peo- ple, including contractors. Going forward, Silver Standard expects to develop a new life-of-mine plan for Marigold, targeting a lower strip ratio and higher grade, with the potential to reduce mining costs. An Detour Lake's mining rates are expected to average 252,000 mt/d in 2014, rising to 389,000 mt/d in 2020. The haulage truck fleet is projected to increase from the current 23 trucks to 41 trucks at the peak of the mine oper- ation from 2026 to 2031, according to project owner Detour Gold. EMJ_pg04-27_EMJ_pg04-27 3/3/14 10:32 AM Page 8