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REGIONAL NEWS - U.S. & CANADA 6 E&MJ; • FEBRUARY 2018 www.e-mj.com Pretium Resources has submitted an application to British Columbia's min- istries of Energy, Mines and Petroleum Resources and of Environment and Cli- mate Change Strategy to increase mine production at its Brucejack mine in northwest British Columbia from 2,700 metric tons per day (mt/d) to 3,800 mt/d. The application, submitted in Decem- ber, reflects an increase to an average of 1.387 million mt/y from 990,000 mt/y. The approval process is expected to take six to 12 months. Engineering is under way to assess re- quired mill capacity upgrades. Based on preliminary engineering, the capital cost to increase mill capacity is estimated to be less than $25 million and will be updated when the engineering process is complete. The Brucejack mine reached commer- cial production on July 7, after pouring its first gold on June 30. During the three months ended September 30, the mine produced 82,203 ounces (oz) of gold and 83,233 oz of silver from low-grade stock- piles, development muck, and stope ore. In July, the mill feed was predom- inantly from low-grade stockpiles and development muck. As the mine ramp- up progressed through the quarter, more stope ore was fed directly to the mill, which improved production results. Brucejack is an underground mine lo- cated approximately 950 km northwest of Vancouver and 65 km north of Stewart, British Columbia. Mine design at start- up called for production of an average of 504,000 oz/y of gold over its first eight years of operation and a mine-life average of 404,000 oz/y over 18 years. All-in sus- taining costs of production are estimated at $445/oz. Stopes are mined using a combination of longitudinal and transverse mining, de- pending on zone width and orientation. Ore is processed using a combination of conventional sulphide flotation and gravi- ty concentration to recover gold and silver. Brucejack's gold reserves are currently estimated at 8.7 million oz at a life-of- mine grade of 14.1 g/mt (16.1 g/mt in years 1 to 10). Corps of Engineers Approves Pebble Permit Application On January 6, the U.S. Army Corps of Engineers published a notification that the permit application submitted by the Pebble Ltd. Partnership, owned by North- ern Dynasty Minerals, had been accept- ed. This formally begins the permitting process under the National Environmen- tal Policy Act (NEPA) review process and other permitting efforts associat- ed with the project to develop the cop- per-gold-molybdenum porphyry deposit in southwest Alaska as an open-pit mine. The company's application incorporates more than a decade of third-party envi- ronmental research. Pebble Partnership CEO Tom Collier said the Pebble team has redesigned the project in response to stakeholder concerns. The development proposed is substantially smaller than previous it- erations, and presents significant new environmental safeguards, including a development footprint less than half the size previously envisaged; the consolida- tion of most major site infrastructure in a single drainage (the North Fork Koktu- li), and the absence of any primary mine operations in the Upper Talarik drainage; a more conservative Tailings Storage Fa- cility (TSF) design, including enhanced buttresses, flatter slope angles and an improved factor of safety; separation of potentially acid generating (PAG) tailings from non-PAG bulk tailings for storage in a fully-lined TSF; no permanent waste rock piles; and no cyanide usage. "These are very substantial improve- ments that we have made over the past few years in response to issues and con- cerns raised by project stakeholders," Collier said. "We believe that as Alaskans become more familiar with our proposed project design and the environmental safeguards it incorporates, there will be an increasing degree of support for the pro- ject, and the significant economic poten- tial it represents for the state of Alaska." Following four years of construction activity, the proposed Pebble mine will operate for a period of 20 years. This includes 14 years of mining using con- Pretium Plans Major Mine Production Increase at Brucejack Brucejack in northwest British Columbia produced more than 82,200 oz of gold in the third quarter of 2017. Stopes are mined using a combination of longitudinal and transverse mining.