|Uranium? Well, It’s Uh . . .|
More than half the world’s production of uranium comes from mines in Canada and Australia. At 28%, Canada produces the largest share. In fact, Canada produced a whopping 11628 tonnes of uranium in 2005. Yet the average Canadian knows little about uranium.
What is uranium?
One of the more common natural elements in the earth’s crust, uranium is a metal capable of generating enormous amounts of energy. Large deposits have been found everywhere on earth except Antarctica. In a nuclear reactor, uranium’s heat is harnessed to generate energy without producing greenhouse gases. Uranium is virtually everywhere. Even your backyard is apt to contain a half pound of the stuff. Scientists believe heat from the element’s radioactive decay keeps the earth’s core in its molten state. Uranium is the heaviest of all naturally occurring elements.
Is uranium dangerous?
Uranium is radioactive, making it dangerous to living organisms exposed to high doses. However, science has harnessed the use of this radioactivity. Today, the element helps to generate electricity. A seven-gram pellet of uranium contains as much energy as 3.5 barrels of oil, 17,000 cubic feet of natural gas, or 1,780 pounds of coal. Uranium is also used in food safety, space exploration, and radiation to treat cancer patients. Annual radiation exposure from a nuclear power plant is less than a passenger receives on a single long flight in a jet airliner. Contrary to popular misconception, commercial nuclear power plants don’t explode. That is because their fuel is enriched only to a maximum of 4% Uranium 235 – insufficient to cause a nuclear explosion.
Near Saskatchewan’s Athabasca Basin lie
Near Saskatchewan’s Athabasca Basin liethe world’s richest uranium deposits. All of Canada’s high-grade mines are located in this area. Grades, or the uranium concentration of these deposits, are as much as 100 times the grade of the world average. COGEMA Resources Inc (30%) and Cameco Corporation’s (70%) McArthur River Mine has the highest-grade ore worldwide, averaging 25%. McArthur River also has enormous reserves and, in 2005, produced more than 17% of the world’s uranium. Higher grades and larger reserves make mining the ore more economically viable. Because these deposits are located so deep in the earth, new methods had to be developed to mine them.
Canadian exploration is concentrated in northern Saskatchewan, but there are also prospects in Labrador and the Northwest Territories.
Saskatchewan’s uranium is mined to produce uranium oxide (U308) or yellowcake, which is further processed for nuclear reactor fuel to produce electricity. About 16% of the world’s electricity is generated by nuclear power plants, compared to 39% coal and 19% hydro. About 15% of Canada’s electricity comes from nuclear power, with 18 reactors providing 12,500 megawatts of power.
McArthur River Mine in northern Saskatchewan
Photo by Shirley Collingridge
How do they get uranium safely out of the ground?
Advanced technology has made available the richest deposits, deep underground. Because their grade is so high, extreme measures are in place to protect workers and the environment. In 2005, 30% of uranium was mined from open pits. Thirty-eight per cent came from underground mines, 21% from in situ leaching (ISL) and 11% as by-products.
Ground freezing and high-pressure water jets can now be used to excavate ore.
While heavily regulated and monitored, these new methods can still experience problems. At Cigar Lake’s 450 meter deep underground mine, major flooding in October set the project back at least a year.
What about waste products?
The mandate of Canada's Nuclear Waste Management Organisation (NWMO) is to explore options for storage and disposal, make proposals to the government, and implement what is decided.
Reactor Site Extended Storage at seven sites has been found feasible, requiring only some further dry storage facilities to be built. Centralised Extended Storage is similar to longer-term systems already operating in 12 countries. This would involve dry storage, with two options on the surface and two below ground level.
A third possibility is a deep geological repository which would allow later retrieval. That option involves burying nuclear waste 500 to 1000 metres deep in the stable rock of the Canadian Shield. Containers would be packed in bentonite clay and stored below the table water.
Recommendations in 2005 suggested that the country's spent fuel be placed in a deep geological repository, retrievably, but not until there has been a further 18 years of public discussion to identify a site.
The utilities and AECL remain responsible for low and intermediate-level wastes. These are stored above ground; a longer-term facility for Ontario is being considered for about 2015.
In 2006, the Canadian government announced a 5-year, C$520 million program to clean up legacy wastes from research and development of nuclear power, medical isotopes and early military activities to the 1950s.
What about military use?
Today, Canada's uranium is sold only for electrical power generation only. Other equipment and services are also only for peaceful uses. Canada is party to the Nuclear Non-Proliferation Treaty (NPT) as a non-nuclear weapons state.
Created by: Shirley Collingridge, Wordsmith