Engineering & Mining Journal

SEP 2018

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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Page 9 of 75

REGIONAL NEWS - U.S. & CANADA 8 E&MJ • SEPTEMBER 2018 Donlin Gold Project Receives ROD, Major Federal Permits The U.S. Army Corps of Engineers (the Corps) and the U.S. Bureau of Land Man- agement (BLM) have issued a single Fed- eral Record of Decision (ROD) for Barrick Gold's Donlin Gold project, located in Alaska, following completion of the fed- eral National Environmental Policy Act process. Along with the ROD, the Corps issued a combined permit under Section 404 of the Clean Water Act and Section 10 of the Rivers and Harbors Act. Addi- tionally, the BLM issued the offer to lease for the right-of-way for those portions of the natural gas pipeline that would cross federal lands. "As one of the largest undeveloped gold deposits in the world, Donlin Gold represents exceptional optionality within our portfolio," said Rob Krcmarov, execu- tive vice president, exploration and growth for Barrick. "Now, with key permits in hand, we can concentrate on further ex- ploring ways of reducing initial capital and unlocking the value of this asset for all of our partners, in keeping with our deep commitment to community engagement and environmental stewardship." Greg Lang, NOVAGOLD's president and CEO, said the ROD serves as the foun- dation for issuance of the federal permits required for them to build a technically, environmentally, financially responsible, and socially sustainable operation. Donlin Gold has the potential to pro- duce, on average, more than 1 million ounces per year over a 27-year mine life. Donlin Gold LLC is an Alaska-based company owned equally by NovaGold Re- sources and Barrick Gold. Aquila Advances Back Forty Zinc-Gold Project in Michigan Aquila Resources has reported the results of an independent, open-pit-only feasibil- ity study of its 100% owned Back Forty zinc and gold project on Michigan's Up- per Peninsula. Project life is estimated at seven years, producing an average of 67,000 ounces per year (oz/y) of gold in doré and 73 million lb/y of zinc in con - centrates, as well as separate copper and lead concentrates. Initial project capital costs are estimated at $294 million. The feasibility study is based on prov- en and probable open-pit mineral re- serves totaling 11.65 million metric tons (mt), grading 1.85 g/mt gold, 2.64% zinc, 21.7 g/mt silver, 0.28% copper, and 0.21% lead. The process plant de- sign is based on a flexible metallurgical flowsheet designed for treatment of a variety of different ore types. Nominal throughput is planned at 4,000 mt per day (mt/d) of sulphide ore and 800 mt/d of oxide ore. Mineralization at the Back Forty pro- ject consists of discrete zones of zinc- rich or copper-rich massive sulphides, with or without lead, that may contain significant amounts of gold and sil- ver; stockwork stringer and peripheral sulphides that can be gold-, zinc- and copper-bearing, with or without lead and silver; precious-metal-only low-sul- phide mineralization; and oxide-rich pre- cious-metal-bearing gossan. The mining operations will be based on a large open pit that will be mined in three pushback phases using blast hole drills, hydraulic excavators and 91-mt haul trucks. Support equipment will in- clude dozers, graders, water trucks, and light vehicles for maintenance, personnel transport, and mine supervision. Sulphide mineral reserves that will be processed through the flotation concen- trator have been classified into five ore types from three zones. Project value will be maximized by campaigning the differ- ent sulphide ore types through the plant separately, with the minimum duration of any campaign being approximately one month. A total of seven different ore stockpiles will be used to facilitate cam- paigning and also ensure that both the sulphide and oxide process plants are fed the highest-value ore available. The oxide process plant flowsheet in- cludes crushing, grinding, classification, pre-leach thickening, cyanide leach, CCD washing and clarification of pregnant solution, de-aeration and Merrill Crowe zinc precipitation, mercury removal using a retort, and smelting to produce doré. Some pre-construction activities have begun at the Back Forty project. Aqui- la is finalizing a project execution plan that will further define the project devel - opment strategy, including contracting philosophy, plans for basic and detailed On August 13, Col. Michael Brooks, commander of the U.S. Army Corps of Engineers, Alaska District, and Joe Balash, U.S. Department of the Interior's assistant secretary of land and minerals management, sign the first joint record of decision nationwide between the Corps and the Bureau of Land Management for the Donlin Gold mine project during a signing ceremony at the district headquarters building on Joint Base Elmendorf-Richardson.

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