The Meadowbank Complex refers to the processing facilities and infrastructure at the Meadowbank mine site combined with the mining and infrastructure at the Amaruq site. The 127,042-hectare Amaruq property is located approximately 50 km northwest of the Meadowbank mine site, with a 64-kilometre road connecting the two sites.
The Meadowbank gold mine achieved commercial production in March 2010 and produced its three millionth ounce of gold in 2018. The final year of production at the Meadowbank mine was 2019, with mining operations at the Complex gradually transitioning to Amaruq, which today provides the sole source of mill feed. The Company declared commercial production at the Whale Tail pit at Amaruq in September 2019.
Discovered in 2013, Amaruq hosts the Whale Tail gold deposit as well as the IVR (V Zone) deposit, Mammoth Zone and several other targets. At December 31, 2022, the Amaruq property was estimated to contain open pit proven and probable mineral reserves of 1.4 million ounces of gold (12.4 million tonnes grading 3.56 g/t gold), and underground proven and probable mineral reserves of 748,000 ounces of gold (4.2 million tonnes grading 5.49 g/t gold), as well as substantial open pit and underground indicated and inferred mineral resources.
The Amaruq mining operation uses the existing infrastructure at the Meadowbank mine, including mining equipment, mill, tailings facilities, camp and airstrip. Additional infrastructure has been built at the Amaruq site, including a truck shop/warehouse, fuel storage and a second camp facility. Amaruq ore is transported using long haul off-road type trucks to the mill at the Meadowbank facilities for processing.
The life of mine plan for the Whale Tail pit calls for the production of approximately 2.5 million ounces of gold between 2019 and 2026.
The IVR pit achieved commercial production on December 31, 2020.
In February 2021, the Board approved the construction of the Amaruq underground project and first gold was poured in late 2021 with commercial production achieved on August 1, 2022. The objective is to mine higher-grade underground portions of the deposit in conjunction with the open pits.
Amaruq achieved its record annual production of 373,785 ounces of gold in 2022, eclipsing prior year production by approximately 50,000 ounces of gold and increasing annual mill throughput by over 300,000 tonnes (including pre-commercial production).
Geology
The Meadowbank and Amaruq properties are underlain by Archean-age volcanic and sedimentary rocks of the Woodburn Lake Group. This is within the Rae domain of the Western Churchill geological province of the Canadian Shield. These rocks were possibly deposited in a continental rift setting and consist of mafic to ultramafic volcanic rocks interlayered with carbon-rich sedimentary rocks. The rock sequence has since been intruded by granitoid rocks and lamprophyres, and has been affected by multiple phases of ductile deformation along with metamorphism to greenschist facies and locally to the upper greenschist facies.
Mineralization
Gold deposits at the Meadowbank property are found along two main structural features that cross the property: the 25-km-long Meadowbank Trend and the Pipedream Lake (Northeast) Trend. The Meadowbank Trend hosts the Goose, Portage and Vault deposits (all now mined out). 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. These shallow deposits lie within 7 km of each other. A fourth deposit named PDF has been outlined on the Northeast gold trend.
At the Amaruq property, three significant zones of gold-bearing quartz-pyrrhotite-arsenopyrite veining/flooding within volcano-sedimentary rocks have been discovered: Whale Tail, V Zone (IVR) and Mammoth. The Whale Tail and V zones appear to be offset mineralized corridors striking east-northeast to northeast and dipping moderately to steeply southeast.
The Whale Tail deposit has been defined over at least 2.3 km of strike length and from surface to 1,000 metres depth; it includes the Whale Tail ore shoot in the mineralized chert-iron formation sequence plunging shallowly east-to-northeast. Whale Tail remains open at depth and along strike.
Immediately north of Whale Tail, the V Zone consists of a series of parallel stacked mineralized structures, striking northeast and extending from near surface to as deep as 707 metres below surface; the southeast dip of the structures is approximately 30 degrees near surface and steepens to 60 to 70 degrees at depth, where there are at least two sub-parallel structures. The V Zone ore shoot, defined in 2018, is a mineralized corridor 100 to 150 metres wide, locally more than 300 metres wide, plunging shallowly eastward, extending from approximately 350 metres to more than 700 metres depth.
The Whale Tail and V zone deposits come together at depth northeast of Whale Tail Lake.
Mining
Mining concluded at the Meadowbank site in 2019.
At Amaruq, a conventional open-pit mining operation has been developed at the adjacent Whale Tail and V Zone deposits, with ore being transported using long haul off-road type trucks to the mill at the Meadowbank facilities for processing. Following construction of two associated water retention dikes, mining from the Whale Tail pit began in the first quarter of 2019 with commercial production declared on September 30, 2019 and commercial production was declared at the IVR pit on December 31, 2020.
The underground mining operation at Amaruq achieved commercial production on August 1, 2022. New facilities were added at the Amaruq site to support the underground project, including: a new mine dry, surface ventilators, cemented rock fill plant, compressor room, new generators, a new electric house, and a high-pressure grinding-roll unit.
The existing exploration portal and ramp that connect the Whale Tail and V Zone deposits are being used for development and production at the Amaruq underground operation. Long-hole open stoping is used for underground mining and stopes are backfilled using cemented rockfill. A traditional truck and scoop tram approach is used for underground mucking and hauling. Once at surface, ore is hauled by a long haul, off-road truck fleet to the mill at the Meadowbank facilities for processing.
The mining rate at Amaruq underground is set to gradually ramp-up to approximately 2,300 tpd. Over the five-year mine life, the average mining rate is expected to be approximately 2,000 tpd.
The current mine life for the Amaruq mine is 2026.
Processing
The process design at the Meadowbank mill consists of two-stage crushing, grinding, gravity concentration, cyanide leaching and gold recovery in a CIP circuit with a current capacity of 3.6 million tonnes processed per year (9,840 tonnes per day).
The Meadowbank gold processing plant uses conventional technology adjusted to the Arctic climate. After two stages of crushing and grinding, any "free gold" is then recovered by a gravity circuit. The remainder is leached using cyanide, with the gold captured using carbon-in-pulp (CIP) technology and electrowinning cells. Gold-plated cathodes and gravity concentrate are smelted in an induction furnace and poured as doré bars.
The CIP tailings are treated for the destruction of cyanide using the standard sulphur-dioxide-air process. The detoxified tailings are then pumped to the permanent tailings facility. The tailings storage is designed for zero discharge, with all process water being reclaimed for re-use in the mill to minimize water requirements. Permitting for in-pit disposal of the Meadowbank mill tailings in the depleted Meadowbank pits was received and in-pit tailings deposition began in July 2019.
Exploration
The Whale Tail deposit has been defined over at least 2.3 km of strike length and from surface to 915 metres depth.
The Whale Tail deposit remains open to the west at depth, and to the east along a shallow plunge corresponding to the main ore shoot. A small portion of Amaruq's current mineral reserves and mineral resources are in the Whale Tail North structure.
The V Zone consists of a series of parallel, stacked mineralized structures striking northeast from near surface to as deep as 707 metres below surface.
At the Meadowbank Complex in 2023, the Company expects to spend approximately $8.4 million for 32,000 metres of expensed exploration drilling, focused on testing open-pit and depth extensions of mineralization and the potential for further underground deposits at the Amaruq satellite operation.
The Company expects to spend an additional $6.7 million for 8,000 metres of drilling to investigate for new, near-surface satellite deposits close to the road and infrastructure around the Meliadine and Meadowbank/Amaruq operations. Any new discoveries at open-pit depths have the potential to extend the life of each mine in conjunction with the extensions of higher-grade underground mineralization at each site.