The Voisey’s Bay nickel mine located in Labrador, Canada is undergoing a major expansion to transition from open-pit to underground operations.
Owned and operated by Brazilian miner Vale, the nickel mine has been producing nickel, copper, and cobalt since 2005.
Vale sanctioned the £1.4bn ($1.7bn) expansion project to develop two underground deposits at the mine site in July 2015, and the construction works for the same were started in 2016.
Although the expansion project was temporarily suspended due to poor market conditions in 2017, it was relaunched with the first rock blast for an underground mine portal in October 2018.
The existing open-pit mine is expected to operate until 2021 while the Voisey’s Bay underground operations, scheduled for commissioning in 2022, are expected to extend the mine life until 2034.
Nickel, copper, and cobalt production at Voisey’s Bay
The Voisey’s Bay nickel mine produced approximately 35.400 tonnes (t) of nickel, 25,000t of copper, and 1,600t of cobalt in concentrate in 2019.
The mine was placed under care and maintenance due to the Covid-19 pandemic in March 2020. Vale, in June 2020, however, announced to resume operations at Voisey's Bay in July 2020 and reach full capacity in August 2020.
The Voisey’s Bay underground project is expected to produce up to 45,000t of nickel, 20,000t of copper, and 2,600t of cobalt a year.
Location, geology, and mineralisation
The Voisey’s Bay nickel mine is situated on the coast of Labrador in the Newfound and Labrador Province of Canada.
Hosted within the 20,000km2 batholithic Nain Plutonic Suite (NPS), the polymetallic deposit is located on a peninsula in northern Labrador which is bordered to the north by the Anaktalak Bay and to the south by the Voisey's Bay.
The property lies approximately 35km southwest of Nain, 80km northwest of Utshimassits, and approximately 900km north-northwest of St. John’s, the capital of the Newfound and Labrador Province.
The Voisey’s Bay ore body is characterised by disseminated sulphide mineralisation. The current open-pit operation is based on the Ovoid deposit, while the expansion project is based on Reid Brook and Eastern Deeps underground deposits.
Ore reserves at the Voisey’s Bay nickel mine
The Voisey’s Bay nickel mine was estimated to hold approximately 28.9 million tonnes (Mt) of proven and probable ore reserves grading 2.11% nickel, 0.92% copper, and 0.13% cobalt.
Mining and ore processing
The conventional open-pit mining involving drill, blast, load and haul methods are being implemented for extracting ore from the Voisey’s Bay open-pit nickel mine.
Mining is carried out in 5m benches and the extracted ore loaded into 50t wheel loaders for transportation to a nearby 6.000 tonnes per day (tpd) concentrator facility.
The run-of-the-mine ore undergoes crushing, grinding, floatation, thickening, and dewatering for the production of two types of concentrate including the nickel-cobalt-copper concentrate and the copper concentrate.
The nickel concentrate from the Voisey’s Bay concentrator facility is shipped to Vale’s hydrometallurgical processing facility in Long Harbour, Newfoundland for the production of finished nickel and associated copper and cobalt products.
Cobalt stream deals for the Voisey’s Bay mine
Vale concluded two cobalt stream agreements for a combined 75% of the total cobalt output of the mine with Wheaton and Cobalt 27 in June 2018. Cobalt 27 will have a 32.6% stake in the total cobalt by-products of the Voisey’s Bay nickel mine from January 2021 onwards, while the remaining 42.6% will be claimed by Wheaton.
Vale received a total of £510m ($690m) in cash for these two cobalt stream deals for the mine.
The Voisey’s Bay nickel mine is accessed through a road that directly leads to the Ovoid deposit.
The electricity for the project is sourced from an on-site power generation facility comprising six diesel generators with a total rated output of up to 14MW.
The water for the project is supplied from Camp Pond through a pumphouse facility and pipeline connecting the mine site.
The mine site currently houses an accommodation complex for 255 people.
As part of the underground expansion, two underground mines will be developed and the ore bodies will be accessed through declines from the surface.
The project will also involve the construction and installation of new supporting infrastructure including maintenance facilities, material handling facilities, a paste fill system, as well as underground mine ventilation systems.
The project will also include upgrades and expansion to the existing surface infrastructure including the power and heat generation facility, expanded accommodation, offices, and warehousing space, as well as the upgrade to the water and sewage treatment facilities.
SEM-Hatch, a joint venture between Hatch and Sikumiut Environmental Management (SEM) was contracted for the engineering and project management services for the Voisey’s Bay mine expansion project.
BAE Newplan Group, a subsidiary of SNC Lavalin, was contracted to provide the engineering, procurement, and construction management (EPCM) services for the original Voisey’s Bay nickel mine and concentrator facility in June 2003.