Canada

In Canada, uranium ores first came to public attention in the early 1930s when the Eldorado Gold Mining Company began operations at Port Radium, Northwest Territories, to recover radium. Radium is one of the decay products of uranium and is therefore found in all uranium ores.

Exploration for uranium began in earnest in 1942, in response to a demand for defence purposes. By 1956 thousands of radioactive occurrences had been discovered and three years later 23 uranium mines with 19 treatment plants were in operation. The main production centre was around Elliot Lake in Ontario, but northern Saskatchewan hosted some plants. This first phase of Canadian uranium production peaked in 1959 when more than 12 000 tonnes of uranium was produced. This uranium yielded more in export revenue than any other mineral export from Canada that year.

In response to the development of civil nuclear power, uranium exploration revived during the 1970s, with the focus on northern Saskatchewan’s Athabasca Basin. The Rabbit Lake, Cluff Lake and Key Lake mines started up 1975 to 1983. Exploration expenditure in the region peaked at this time, resulting in the discoveries of Midwest, McClean Lake and Cigar Lake. Then in 1988 the newly formed Cameco Corporation discovered the massive McArthur River deposit.

Canada’s share of known world uranium resources is currently about 8%, but it produces almost one fifth of the mined uranium supply (almost 9145 tU in 2011) making it the second largest producer in the world behind Kazakhstan. Most uranium is exported, but about one fifth is used domestically.

Canada has made a transition from second-generation uranium mines (started 1975-1983) to new high-grade ones, all in northern Saskatchewan, making its uranium mining operations among the most advanced in the world.

Cameco operates the McArthur River mine, which started production at the end of 1999. Its ore is milled at Key Lake, which once contributed 15% of world uranium production but is now mined out. Its other former mainstay is Rabbit Lake.

McArthur River has enormous high-grade reserves of over 20% uranium ore at a depth of about 600 metres. It opened at the end of 1999 and is now the largest uranium mine in the world by a wide margin. Remote-control raise-boring methods are used for mining and the ore is trucked 80 km south to the modified Key Lake mill, where it is blended with ‘special waste rock’ to produce 7200 tU/ yr. Tailings are deposited in a mined-out pit. Cameco is the operator and majority owner, with Areva (30.2%) as partner.

Areva Resources operates the McClean Lake mine, which commenced operation in mid 1999. It has new plant and other infrastructure and uses the first mined-out pit for tailings disposal (the ore having been stockpiled). McClean Lake has four open pits and later will become an underground mine. Annual production depends critically on ore grade being treated, though the mine has recently been relicensed to produce as much as 3100 tU/yr.

Cigar Lake will be a 450 m deep underground mine in poor ground conditions, using ground freezing and high-pressure water jets for excavation of ore. High — grade ore slurry from remote mining will be trucked for treatment at Areva’s expanded McClean Lake mill, 70 km north-east to produce 7000 tU/yr from about 2013. A major flood in 2006 and another in 2008 set the project back several years and pushed costs up from C$660 million to more than C$1.8 billion. The joint venture is managed by Cameco which holds 50%, while Areva holds 37%.

Areva’s large Kiggavik deposit in the Nunavut Territory has evident potential, as do several other smaller but significant deposits.