The Meliadine mine is located near the western shore of Hudson Bay in the Kivalliq District of Nunavut, about 25 km north of Rankin Inlet and 290 km southeast of our Meadowbank mine. Meliadine includes seven gold deposits, six of which are part of the current mine plan. The 111,357-hectare property covers an 80-km-long greenstone belt.
Commercial production began at Meliadine on May 14, 2019. The Company anticipates that mining at Meliadine will be carried out through several underground mining operations and open pits over a 14-year mine life. There are numerous opportunities to create additional value at Meliadine, both at the mine and on the large regional land package.
Geology
Archean volcanic and sedimentary rocks of the Rankin Inlet greenstone belt underlie the property. The rock layers have been folded, sheared and metamorphosed. They trend west-northwest, dip steeply to the north, and have been overturned. The rock units are truncated by the Pyke Fault, a regional structure that extends the entire 80-km length of the property
Mineralization
The Pyke Fault and associated secondary structures (i.e., the Lower Fault) appear to control gold mineralization on the property. Along the fault is a series of oxide iron formations that host six of the seven known Meliadine mine deposits. The deposits consist of multiple lodes of mesothermal quartz-vein stockwork, laminated veins and sulphidized iron formation mineralization. The northern, magnetite-rich Upper Oxide iron formation hosts the Tiriganiaq zone, the largest deposit to date with a strike length of approximately 3.0 km at surface and a known depth of 800 m, as well as the Wolf North and Discovery zones. The southern, weakly magnetic Lower Lean iron formations contain the F Zone, Pump, Wolf Main and Wesmeg deposits. Normeg is hosted by mafic volcanics and is located between the Wesmeg and Tiriganiaq zones.
The deposits are all within 5 km of Tiriganiaq except for Discovery, which is 17 km east-southeast of Tiriganiaq. Each of these deposits has mineralization within 120 m of surface, making them potentially mineable by open pit methods. They also have deeper mineralization that could potentially be mined with underground methods, which are currently being considered in various studies.
Mining
In Phase 1 of the mine, the ore is being sourced entirely from underground with access by decline, using long-hole mining methods. The first three stopes were blasted and mucked out in late 2018. Each stope is backfilled, with cemented pastefill used in primary stopes and dry rockfill for the secondary stopes. A saline water treatment plant treats underground dewatering water; the Company received the necessary approval to discharge the treated saline water to Hudson Bay commencing in the third quarter of 2019.
The current Meliadine mill has shown that it can operate well in excess of its nameplate 3,750 tonnes per day capacity. As a result, the Company has decided to accelerate the Phase 2 expansion to utilize this extra mill capacity. The initial source of open pit ore will be from two pits developed on the Tiriganiaq deposit, which contain probable mineral reserves of 590,412 ounces of gold (3.8 million tonnes grading 4.89 g/t gold).
Processing
Initial ore processing commenced in early February 2019 using low-grade stockpiles. The mill employs a conventional gold circuit comprising crushing, grinding, gravity separation and cyanide leaching with a carbon-in-leach circuit, followed by cyanide destruction and filtration of the tailings for dry stacking. Metallurgical recoveries are expected to average 96%. Phase 1 mill capacity is approximately 3,750 tonnes/day, increasing in Phase 2 to approximately 6,000 tonnes/day.
Exploration
Exploration drilling is currently conducted from surface, while conversion drilling is being done from surface and underground set-ups along the ramps. Additional drilling is planned to expand and upgrade the existing mineral resource base in the immediate mine area.