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10 E&MJ; • DECEMBER 2015 www.e-mj.com REGIONAL NEWS - U.S. & CANADA Richmont Considering Deeper Mining at Island Gold Richmont Mines has completed a prelimi- nary economic assessment (PEA) of devel- opment of mineral resources between the 450- and 860-m levels below surface at its currently operating underground Island Gold mine 83 km northeast of Wawa, Ontario. The PEA considered an 800-met- ric-ton-per-day (mt/d) mining operation. The Island Gold mine is accessed via ramp from surface and is mined by long- hole stoping methods. The mill processed 181,785 mt of ore during the first nine months of 2015 at a head grade of 7.20 g/mt gold and recoveries of 97% to pro- duce 40,837 oz of gold. The PEA considers mining on three new long-hole horizons between the 450-m and 860-m levels. Following a transitional peri- od in late 2015 and 2016, mining from 2017 to 2022 at a rate of 800 mt/d and an expected average diluted mined grade of 8.67 g/mt is projected to produce an average of 78,000 oz/y of gold. Access to the lower levels is planned through continued development of existing internal ramps and raises. Mine utilities and the ventilation system will be extend- ed from the existing infrastructure. The PEA indicates that once mining activities reach the third mining horizon in the first half of 2017, mining production has the potential to be increased to 1,150 mt/d. Capital expenditures related to under- ground development, infrastructure, and milling and tailings facilities for the proj- ect are estimated at C$62 million. The PEA base case estimates average cash costs of production of approximately $552/oz for the 2017-2022 period. Total sustaining capital costs for 2017-2022 are estimated at C$40.5 million, with the majority of these expenditures in the first three years. Richmont CEO Renaud Adams said, "Our growing confidence in the potential of the Island Gold mine underpins our long- term vision for this core asset, with the study being just the first step in unlocking that potential.... While the potential 1,150-mt/d expansion scenario indicates the utilization of a dedicated haulage ramp as the preferred option, we also see poten- tial for additional mineral resources below the 1,000-m level. We will therefore con- tinue to evaluate the potential for an inter- nal shaft system in conjunction with the ramp system as we gain additional infor- mation from our drilling programs." The PEA for the mine-deepening pro- ject was based on measured and indicated resources of 200,096 oz of gold in 626,095 mt at an average grade of 9.94 g/mt and inferred resources of 442,067 oz in 1.2 million mt at an average grade of 11.04 g/mt. The PEA does not take into consideration the exploration potential of the deposit both laterally and at depth. Any additional resources identified by Richmont's 2015 exploration and delin- eation drilling program will be incorporated into a year-end 2015 mineral resource update, which will be part of a further eval- uation process. PEA Supports Renewed Mining at Sleeper Property Paramount Gold Nevada has announced the results of a preliminary economic assessment (PEA) of its 100% owned Sleeper gold project in northwest Nevada. The project includes the historic Sleeper open-pit mine, which operated from 1986 to 1996 and produced 1.66 million oz of gold and 2.3 million oz of silver. Metal Mining Consultants (MMC) con- ducted the Sleeper PEA. The study's base- case scenario assumes open-pit mining and a 30,000-mt/d heap-leach facility hav- ing throughput capacity of about 11 mil- lion mt/y. Production would average 102,000 oz/y of gold and 105,000 oz/y of silver for seven years, with an additional 37,850 oz of gold and 30,500 oz of silver recovered during final leaching. The gold grade would average 0.47 g/mt over the first three years and 0.41 g/mt over the life of the mine. Initial capi- tal is estimated at $175 million, with a payback period of 2.7 years. Projected life- of-mine all-in capital, operating, and sus- taining costs are estimated at $869/gold equivalent oz. The PEA assumed $1,250/oz gold and $16/oz silver prices. Processing facilities would be based on standard cyanide heap leaching, with a carbon-in-column and adsorption-desorp- tion recovery plant. The plant would pro- duce a doré product for direct sale to a regional refinery. Existing infrastructure at the Sleeper mine site would require upgrades; however, the basic components remain in place. The site is currently connected to the regional electrical grid; however, a substantial capacity upgrade would be required. Existing shop and office buildings are located on top of mineable material and would require removal and reconstruction. In addition to the base-case scenario, MCC also evaluated a combined heap- leach and bio-oxidation scenario to test its A recently completed PEA for the Island Gold mine, pictured here, considers mining on three new long-hole hori- zons between the 450-m and 860-m levels, boosting the mine's production to 800 mt/d.