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8 E&MJ; • JUNE 2014 www.e-mj.com REGIONAL NEWS - U.S. & CANADA Baffinland Receives Approval to Ship from Mary River Baffinland has received Canadian federal government approval to start "early-rev- enue-phase" shipping of iron ore from its Mary River project on northwest Baffin Island. The approval from the federal min- ister of aboriginal affairs and northern development followed a positive recom- mendation by the Nunavut Impact Review Board. During the project's early revenue phase, Baffinland will be allowed to ship 3.5 million metric tons per year (mt/y) during the open-water summer shipping season and expects to make its first ship- ment during the 2015 season. Baffinland is owned 50% by Arcelor- Mittal and 50% by Nunavut Iron Ore, with ArcelorMittal as the project operator. The Mary River project is located well within the Arctic Circle and hosts a number of high-grade lump and fine iron-ore deposits that can be mined, crushed and screened into saleable products. Baffinland has a long-term goal of developing the project's Deposit No. 1 to produce between 18 million and 30 mil- lion mt/y of iron ore, operating year-round. The deposit has current measured and indicated resources of more than 350 mil- lion mt at an average grade of more than 64% iron. Construction at the mine site began during the second quarter of 2013, and mining of iron ore is scheduled to begin during the third quarter of 2014. The Mary River site is one of the most isolated mining sites in the world and will be the first large open-pit mine in North America at this latitude. The project area experiences very cold temperatures that average minus 30°C in the winter, with 24- hour darkness from November to January. Summers bring 24-hour daylight from May to August but continued cool to cold condi- tions. These conditions, noted the compa- ny, require special consideration in the planning and logistics of most project activ- ities, but especially shipping, procurement, construction and field investigations. PEA Supports Restart of Trevali's Caribou Mine Trevali Mining has announced the results of a preliminary economic assessment (PEA) for restarting production at its Caribou underground zinc-lead-silver mine and mill complex in the Bathurst mining camp of northern New Brunswick, Canada. Trevali acquired the inactive Caribou oper- ation from Maple Minerals in November 2012. The mine and mill had operated for approximately 13 months prior to going into receivership in 2008 due to depressed commodity prices. The base case PEA for reactivation of the 3,000-metric-ton-per-day (mt/d) Caribou operation indicates positive economics at a pre-production capital expenditure of $36.3 million to produce approximately 93 million lb/y of zinc, 32.5 million lb/y of lead, 3.1 million lb/y of copper, 730,000 oz/y of sil- ver, and 1,500 oz/y of gold in concentrates. Life-of-mine cash costs are estimated at $0.46/lb of zinc equivalent over a mine life of 6.3 years. "We welcome this preliminary econom- ic assessment for our Caribou mine, with scheduled commissioning of operations in the first half of 2015," Trevali President and CEO Mark Cruise said. "These results model a respectable return based on this initial base-case model, and we believe that there is excellent potential for addi- tional optimization given that approximate- ly 3 million mt of mineralized material is presently not included in the mine plan and the deposit remains open for expansion." The base case Caribou PEA uses price assumptions of $1/lb zinc, $1/lb lead, $3/lb copper, $21/oz silver, and $1,200/oz gold. Underground operations will take advantage of in-place development and infrastructure, with a centralized ramp trucking system serving as the main access for the mine. Mining will primarily be conducted using the Modified Avoca method with waste-rock backfill, with the exception of a longhole retreat mining method for partial sill pillar recovery near the end of mine life. The processing plant's milling circuits will include fine-grinding using IsaMills to optimize metallurgical recovery of the fine- grained sulphide mineralization in the dis- trict, followed by standard sulphide flota- tion recovery circuits to produce three con- centrates: zinc, lead-silver and copper-gold. The average life-of-mine modeled head grade for mill feed is 6.11% zinc, 2.49% lead, 0.34% copper, 67.9 g/mt silver, and 0.86 g/mt gold. The restart of Caribou operations repre- sents the initial development phase of Trevali's longer-term plans for its Bathurst camp properties. Subject to ongoing tech- nical studies, the company is looking at the potential for a second stand-alone milling facility to support development of its fully permitted Halfmile mine and the Stratmat Baffinland's initial long-term plans for the Mary River property—one of the most isolated mining sites in the world—targets production of 18 million to 30 million mt/y of iron ore from Deposit No. 1 in a year-round operation. EMJ_pg04-45_EMJ_pg04-45 6/4/14 9:00 AM Page 8