The Meadowbank gold mine achieved commercial production in March 2010, and produced its two millionth ounce of gold in 2015. It has 0.7 million ounces of gold in proven and probable reserves (8 million tonnes at 2.69 g/t) as of December 31, 2016. Meadowbank is expected to produce 320,000 ounces of gold in 2017, and 165,000 ounces gold in 2018.
Studies are ongoing to reduce the potential production gap between the end of the mine life at Meadowbank and the start of operations at Amaruq in 2019.
Agnico Eagle has approved the Amaruq satellite deposit at Meadowbank for development pending the receipt of the required permits, which are currently expected to be received in the third quarter of 2018. Production is currently forecast to begin at Amaruq’s Whale Tail deposit in the third quarter of 2019.
Operations update
- In the second quarter of 2017, payable gold production totalled 95,289 ounces at a production cost per ounce of $571 and a total cash cost per ounce of $559 on a by-product basis. The mine also produced 65,000 ounces of silver in the quarter.
- During the quarter the mill processed 996,000 tonnes of ore (10,948 tonnes/day), with production costs per tonne of C$73 and mine-site costs at C$73 per tonne.
- In the first half of 2017, payable gold production totalled 180,659 ounces at a production cost per ounce of $600 and a total cash cost per ounce of $573 on a by-product basis. The mine also produced 136,000 ounces of silver in the period.
- During the half the mill processed 1,922,000 tonnes of ore (10,620 tonnes/day), with production costs per tonne of C$75 and mine-site costs at C$73 per tonne.
- Given the positive tonnage and grade reconciliation with the Vault deposit block model, the Company now expects to extend production activities at Meadowbank through year-end 2018. Additional opportunities are being evaluated in order to further extend production into 2019 and bridge any gap between cessation of mining operations at Meadowbank and commencement of production at Amaruq.
Geology
The Meadowbank property is underlain by Archean-age volcanic and sedimentary rocks. The Goose and Portage deposits are hosted by magnetite-rich iron formation, while intermediate volcanic rocks host most of the mineralization at the Vault deposit farther north. Both the rock units and the gold deposits are tightly folded and structurally complex, sandwiched between granite plutons.
Mineralization
Gold deposits are found along two main structural features that cross the property – the Meadowbank Trend and the Pipedream Lake (Northeast) Trend. The Meadowbank Trend hosts the Goose, Portage and Vault deposits, which are the sites of initial mining. These shallow deposits lie within 7 km of each other. In all deposits, gold mineralization is commonly associated with intense quartz flooding, and the presence of sulphide minerals (pyrite and/or pyrrhotite).
Mining
Meadowbank has conducted surface mining from a series of three pits all within 7 km of the processing plant. Water retention dykes have been built to allow for mining beneath shallow lakes, using a unique in-water dyke construction method. Dewatering of Vault Lake, for example, has allowed the Vault pit to be mined since April 2014. The mine works year-round, using conventional drilling, blasting, truck and shovel methods. Waste rock is used for construction, or dumped in waste storage sites or previously mined-out areas. To minimize acid generation, the sulphide-bearing waste rock is encapsulated in permafrost and capped with an insulating layer of neutralizing rock.
Processing
The 11,000-tonne/day gold processing plant uses conventional technology adjusted to the Arctic climate. Any “free gold” is removed by a gravity circuit. The remainder is leached using cyanide, with the gold captured using carbon-in-pulp technology and electrowinning cells. Gold-plated cathodes and gravity concentrate are smelted in an induction furnace and poured as doré bars. The plant includes both a cyanide recycling thickener and an air-sulphur dioxide cyanide destruction circuit to ensure that no cyanide escapes to the environment. All water from the tailings pond is pumped back to the plant for reuse, making this a zero-discharge system.
Exploration
Exploration is being conducted at the Amaruq satellite deposit, located 50 km northwest of Meadowbank.