The Meadowbank gold mine achieved commercial production in March 2010, and produced its two millionth ounce of gold in 2015. It has 345,000 ounces of gold in proven and probable reserves (5 million tonnes at 2.28 g/t) as of December 31, 2017. Meadowbank mine is expected to produce 220,000 ounces of gold in 2018, and 60,000 ounces gold in 2019, which is anticipated to be the last year of the mine production.
The mine plan at Meadowbank mine extends the production into 2019, which bridges the gap between the cessation of mining activities at Meadowbank and the expected start of operations at Amaruq in Q3 2019. The additional production comes from an extension of the mine plan at the Vault and Phaser pits in 2018 and the Portage pit in 2018 and 2019, supplemented from stockpiles in 2018 and 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 Q2 2018. Production is currently forecast to begin at Amaruq’s Whale Tail deposit in the third quarter of 2019. Amaruq ore will be hauled by truck to the plant at the Meadowbank site for processing. The mining, processing and infrastructure at the Meadowbank mine site and the mining and infrastructure at the Amaruq site are together referred to as the Meadowbank Complex.
Operations update
- In the first quarter of 2018, payable gold production totalled 61,447 ounces at a production cost per ounce of $1,001 and a total cash cost per ounce of $923 on a by-product basis. The mine also produced 60,000 ounces of silver in the quarter.
- During the quarter the mill processed 830,000 tonnes of ore (9,227 tonnes/day), with production costs per tonne of C$94 and mine-site costs at C$88 per tonne.
- The results of an internal technical study on the Amaruq deposit were incorporated into a new NI 43-101 technical report for the Meadowbank Complex, which was filed on Sedar on March 22, 2018.
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 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. The plant will require minor modifications to treat the Amaruq ore, specifically the addition of a continuous gravity and regrind circuit, and is expected to operate at 9,000 tonnes/day.
Exploration
Exploration is being conducted at the Amaruq satellite deposit, located 50 km northwest of Meadowbank.