Some facts and figures associated with the nuclear debate are well summarized at http://www.uic.com.au/nip43.htm.

In the last forty years uranium has become one of the world's most important energy minerals. It is used almost entirely for making electricity, though a small proportion is used for the important task of producing medical isotopes.

Uranium averages about two parts per million of the earth's crust. Traces of it occur almost everywhere. It is more abundant than gold, silver or mercury, about the same as tin and slightly less abundant than cobalt, lead or molybdenum. Vast amounts of uranium also occur in the world's oceans, but in much lower concentrations.

There are many uranium mines operating around the world, in some twenty countries, though more than two thirds of world production comes from just ten mines. Most of the uranium ore deposits at present supporting these mines have average grades in excess of 0.10% of uranium. In the first phase of uranium mining to the 1960s, this would have been seen as a respectable grade, but today some Canadian mines have huge amounts of ore up to 20% U average grade.

Some uranium is also recovered as a by-product with copper, as at Olympic Dam in Australia, or as by-product from the treatment of other ores, such as the gold-bearing ores of South Africa. In these cases the concentration of uranium may be as low as a tenth of that in orebodies mined primarily for their uranium content.

Generally speaking, uranium mining is no different to other kinds of mining unless the ore is very high grade.

Where orebodies lie close to the surface, they are usually accessed by open cut mining, involving a large pit and the removal of much overburden as well as a lot of waste rock. Where orebodies are deeper, underground mining is employed, involving construction of access tunnels and shafts but with less waste rock removed and less environmental impact. In either case, grade control is usually by measuring radioactivity as a surrogate for uranium concentration. (The radiometric device detects associated radioactive minerals which are decay products of the uranium, rather than the uranium itself.)

At Ranger in north Australia, Rossing in Namibia and most of Canada's Northern Saskatchewan mines through to McClean Lake, the orebodies have been accessed by open cut mining. Other mines such as Olympic Dam in Australia, McArthur River, Rabbit Lake and Cigar Lake in Northern Saskatchewan, and Akouta in Niger are underground, up to 600 metres deep. At McClean Lake, mining will be completed underground.

Some orebodies lie in groundwater in porous unconsolidated material and may be accessed simply by oxygenating that groundwater and pumping it out - this is in situ leach (ISL) mining. ISL mining means that removal of the uranium minerals is accomplished without any major ground disturbance. Weakly acidified or alkaline groundwater with a lot of oxygen injected into it is circulated through an enclosed underground aquifer which holds the uranium ore in loose sands. The leaching solution with dissolved uranium is then pumped to the surface treatment plant

Over half of the world's uranium now comes from underground mines, about 27% from open cut mines and 19% from ISL.

Conventional mines have a mill where the ore is crushed, ground and then leached with sulfuric acid to dissolve the uranium oxides. Most of the ore however remains undissolved in the leaching process, and these solids or 'tailings' are then separated from the uranium-rich solution, usually by allowing them to settle out.

At the mill of a conventional mine, or the treatment plant of an ISL operation, the uranium then separated by ion exchange before being dried and packed.

Uranium in Australia

The existence of uranium in Australia has been known since the 1890s. In the 1930s ores were mined at Radium Hill in South Australia to recover minute amounts of radium for medical purposes. As a result a few hundred kilograms of uranium were also obtained and used mostly to produce colours in glass and ceramics.

The first major producer of uranium in Australia was the Government-owned Rum Jungle project in the Northern Territory which operated from 1954 to 1971. It was closely followed by Radium Hill in South Australia, then Mary Kathleen in Queensland.

As a result of intensive exploration in the late 1960s Australia began to emerge as a potential major source of uranium for the world's nuclear electricity production. At the beginning of the 1970s a series of important discoveries was made, particularly in the Northern Territory. Names like Ranger, Jabiluka and Nabarlek, all in the Northern Territory; Yeelirrie in Western Australia; Olympic Dam (Roxby Downs) in South Australia became familiar. Today Australia's share of the world's uranium resources is about 28% and it produces about 20% of the world's mined uranium.

Uranium in 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. A refinery to produce radium was built the following year at Port Hope, Ontario, some 5000 km away.

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 mines with 19 treatment plants were in operation in five districts. 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. The uranium yielded more in export revenue than for any other mineral export from Canada that year.

Uranium exploration revived during the 1970s with the focus on in 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. Today Canada's share of world uranium resources is about 15%, but it produces about one third of the mined uranium.

Other countries with major uranium deposits are Kazakhstan, South Africa, Namibia, Brazil, Russian Federation and the USA.

Table 1

Known Recoverable Resources of Uranium

 

	tonnes U308	percentage of world
Australia	863,000	28%
Kazakhstan	472,000	15%
Canada	437,000	14%
South Africa	298,000	10%
Namibia	235,000	8%
Brazil	197,000	6%
Russian Fed.	131,000	4%
USA	104,000	3%
Uzbekistan	103,000	3%
World total	3,107,000

 

Reasonably Assured Resources plus Estimated Additional Resources - category 1, to US$ 80/kg U, at 1/1/99. Brazil, Kazakhstan and Russian figures above are 75% of in situ totals. Uranium: Resources, Production and Demand 1999, OECD NEA & IAEA, July 2000.

Australia's Uranium Mines

The Nabarlek mine was the first of the uranium deposits discovered in the late 1960s to early 1970s to come into production. The main orebody, which contained about 11,000 tonnes U3O8, was mined and stockpiled when operations commenced in 1979. The stockpiled ore was processed from 1980 to 1988.

The next mine was Ranger, owned by Energy Resources of Australia Ltd (ERA) and located about 230 kilometres east of Darwin. Mining commenced in 1980 and is continuing. Ranger then consisted of two orebodies with a total of approximately 110,000 tonnes of U3O8, but one of these, with half of that ore, is now mined out. Capacity is about 5000 tonnes U3O8 per year.

In 1991 ERA purchased from Pancontinental Mining Ltd. the Jabiluka uranium orebody, some twenty kilometres to the north. This is one of the world's larger known uranium deposits, with reserves containing 71,000 tonnes of U3O8. The Jabiluka lease abuts the Ranger mining lease so subject to relevant approvals, the ore from Jabiluka could be processed to U3O8 at the Ranger mill.

Olympic Dam, 265 km north of Port Augusta in South Australia, commenced operations in 1988. It is potentially one of the world's largest uranium producers with ore reserves containing 370,000 tonnes U3O8, 12 million tonnes of copper and significant amounts of gold and silver. Capacity was increased to 4600 tonnes U3O8 per year in 1999 and there are pans for a further increase to 5600 t/yr.

Beverley, the country's first mine to utilise in situ leaching, commenced operation late in 2000. Both it and Honeymoon, which anticipates 2004 start-up, are in South Australia, and both are small (1000 t/yr) in situ leach (ISL) mines. Most US uranium production is by this method.

Since 1995 Australia has exported an average of about 6500 tonnes of U3O8 per year and the value of this has risen to over A$350 million per year.

Table 2

Summary of In Situ Resources* Available in Operating and Prospective Australian Uranium Mines

Deposit	Grade U3O8	Contained U3O8	category
Olympic Dam	0.05-0.06%	369 000 t	p & p reserves
	0.04-0305%	810 000 t	measured and indicated resources (incl reserves)
Ranger	0.27%	49 000 t	p & p reserves
Jabiluka	0.51%	71 000 t	p & p reserves
Beverley	0.18%	21 000 t	resources
Honeymoon	0.15%	6 800 t	resources
Billaroo West	0.12%	17 600 t	resources
Koongarra	0.8%	14 540 t	p & p reserves
Kintyre	0.2-0.4%	35 000 t	reserves & resource
Yeelirrie	0.15%	52 000 t	indicated resources

* These categories being in accordance with the Australasian Code for Reporting Identified Mineral Resources and Ore Reserves (1992). p & p = proved and probable

Canada's uranium mines

Canada is in the midst of a transition from second-generation uranium mines (started 1975-83) to new high-grade ones, all in northern Saskatchewan.

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, which still has some reserves at Eagle Point, where mining has resumed. Cogema Resources operates the McClean Lake mine, which started production in mid 1999. Its Cluff Lake mine has now closed, and will be decommissioned in 2003.

The McClean Lake mine commenced operation in mid 1999. It is producing about 3000 t/yr U3O8 from 2.4% ore but has been relicensed for 3640 t/yr. It has new plant and other infrastructure and uses the first mined-out pit for tailings disposal (the ore having been stockpiled). McClean Lake involves four open pits and later will become an underground mine. It is owned by Cogema Resources (70%, also operator), in joint venture with Denison Energy (22.5%) and OURD (7.5%).

McArthur River has enormous high-grade (23%) reserves at a depth of c 600 metres. It opened at the end of 1999. 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 8200 t/yr of U3O8. Tailings are deposited in a mined-out pit. Cameco is the operator and majority owner, with Cogema (30.2%) as partner.

There are also two further new uranium projects coming into production in the next few years in N. Saskatchewan.

Cameco's Cigar Lake is planned as a 450 m deep underground mine in poor ground conditions, using ground freezing and high-pressure water jets for excavation of ore. High-grade (22.5%) ore from remote mining will be trucked for treatment at the expanded McClean Lake mill, 80 km northeast, and to Rabbit Lake mill 70 km east, to produce 8200 t/yr U3O8. Government approval was received in 1998, but start-up has been deferred to at least 2006.

Cogema's Midwest mine was to be underground, utilising ground freezing and water jet boring, but may be open pit. The ore will be milled at McClean Lake nearby, to produce 2600 t/yr U3O8. Government approval received in 1998 enabled application for CNSC construction and operating licences.

Table 3

Summary of Resources Available in Operating and Planned Canadian Uranium Mines

mine	operator	tonnes U3O8	av. ore grade	category
Key Lake	Cameco	450	0.41%	proven reserves
Rabbit Lake	Cameco	10,150	1.30%	proven reserves
		900	0.88%	indicated resources
Cluff Lake	Cogema	5,400	1.2%	"resources /reserves"
McClean Lake	Cogema	21,800	2.4%	"resources /reserves"
McArthur River	Camenco	161,300	21.0%	proven reserves
		17,700	23.04%	probable reserves
		66,000	10.74%	indicated resources
Cigar Lake	Cameco	102,670	19.77%	proven reserves
		2,440	4.2%	probable reserves
		53,600	16.95	inferred resources
Midwest	Cogema	16,300	4.5%	"resources /reserves"
Dawn Lake	Cameco	5,800	1.69%	indicated resources

Mining and Processing

At Ranger and most of the Northern Saskatchewan mines through to McClean Lake the orebodies have been accessed by open cut mining. Olympic Dam, McArthur River and Jabiluka are underground, up to 600 metres deep.

At conventional mines, the ore goes through a mill where it is first crushed. Primary crushing breaks up the largest pieces followed by fine crushing to reduce the material to small pieces of about 20 mm and less. The 'fine' ore is then ground in water to produce a slurry of fine ore particles suspended in the water. The slurry is leached with sulfuric acid to dissolve the uranium oxides.

Most of the ore however remains undissolved in the leaching process, and these solids or 'tailings' are then separated from the uranium-rich solution, usually by allowing them to settle out.

The liquid containing the uranium is filtered and the uranium then separated by ion exchange.

Finally the uranium is recovered in a chemical precipitate which is filtered and dried to produce a uranium oxide concentrate, about 99% U3O8. It is then packed into 200 litre steel drums which are sealed for shipment. The U3O8 is only mildly radioactive. (The radiation level one metre from a drum of freshly-processed U3O8 is about half that - from cosmic rays - on a commercial jet flight.)

At Beverley (and prospectively, Honeymoon), mining is by in situ leaching (ISL). This means that the mining is accomplished without any major ground disturbance. Weak acid with a lot of oxygen injected into it is circulated through an enclosed underground aquifer which holds the uranium ore in loose sands. The leaching solution with dissolved uranium is pumped to the surface treatment plant. Uranium is separated by ion exchange and is then recovered as a chemical precipitate of uranium peroxide.

Wastes from Mining and Milling

Solid waste products from the milling operation are pumped as a slurry to a tailings dam. These wastes comprise most of the original ore and they contain most of the radioactivity in it. In particular they contain radium, present in the original ore.

When radium undergoes natural radioactive decay one of the products is radon gas. Because radon and its decay products (daughters) are radioactive and because the tailings are now on the surface, measures are taken to minimise the emission of radon gas. During the operational life of a mine the material in the tailings dam is usually covered by water to reduce surface radioactivity and radon emission (though neither pose a hazard at these levels).

On completion of the mining operation it is normal for the tailings dam to be covered with some two metres of clay and topsoil to reduce radiation levels to near those normally experienced in the region of the orebody, and for a vegetation cover to be established. At Ranger and Jabiluka, tailings will be returned underground, as was done at the now-rehabilitated Nabarlek mine. In Canada ore treatment is often remote from the mine, and tailings are emplaced in mined out pits wherever possible and engineered dams otherwise.

Run-off from the mine stockpiles and waste liquors from the milling operation are collected in secure retention ponds for isolation and recovery of any heavy metals or other contaminants. The liquid portion is disposed of either by natural evaporation or recirculation to the milling operation. Most Australian mines adopt a "zero discharge" policy for any pollutants.

With ISL no tailings are involved and very little waste is generated. The quality of the groundwater returns to normal once the oxygen input is discontinued. ISL thus has clear environmental advantages in the places it can be applied.

Mining methods, tailings and run-off management and land rehabilitation are subject to Government regulation and inspection.

The Health of Miners

In Australia all uranium mining and milling operations are undertaken under the Code of Practice on Radiation Protection in the Mining and Milling of Radioactive Ores. This was drawn up by the Commonwealth in line with recommendations of the International Commission on Radiological Protection (ICRP), but it is administered by state health and mines departments. This Health Code, which was updated in 1995, sets strict health standards for radiation and radon gas exposure, for both workers and members of the public.

In Canada the Canadian Nuclear Safety Commission is responsible for regulating uranium mining as well as other aspects of the nuclear fuel cycle. In Saskatchewan, provincial regulations also apply concurrently, and set strict health standards for both miners and local people.

Uranium itself is only slightly radioactive. However radon, a radioactive gas, is released to the atmosphere in very small quantities when the ore is mined and crushed. Radon, one of the decay products of uranium and radium, occurs naturally in most rocks and minute traces of it are present in the air which we all breathe.

At the relatively high concentrations associated with uranium (and some mineral sands) mining however, radon is a potential health hazard. Consequently special precautions are taken during the mining and milling of uranium ores to protect the health of the workers. These precautions include: 

• Efficient dust control, because the dust may contain radioactive constituents and emit radon gas.
• Limiting the radiation exposure of workers in mine, mill and tailings areas so that it is as low as possible, and in any event does not exceed the allowable dose limits set by the Health Code. In Canada this means that mining in very high-grade ore is undertaken solely by remote control techniques.
• The use of radiation detection equipment in all mines.
• Good forced ventilation systems in underground mines to ensure that exposure to radon gas and its radioactive daughter products is as low as possible and does not exceed established safety levels.
• Imposition of strict personal hygiene standards for workers handling uranium oxide concentrate.

If uranium oxide is ingested it has a chemical toxicity similar to that of lead oxide. Similar precautions to those in a lead smelter are therefore taken when handling it.

Government Policy: Australia

In 1953 the Australian parliament passed the Atomic Energy Act which set in train research on nuclear energy and plans to construct a nuclear power reactor south of Sydney. However, this project was abandoned in 1972 and the focus reverted to developing enrichment technology which might add value to the country's uranium.

In 1975 the Australian Government set up the Ranger Uranium Environmental Inquiry - often referred to as the 'Fox Inquiry', to investigate and advise on both uranium policy in general and on uranium mining in the Alligator Rivers area in particular. It lasted almost two years, heard 303 witnesses and produced two reports which identified concerns about some aspects of the use of nuclear energy and urged caution at all stages.

Following publication and consideration of the Inquiry's Reports, the Federal Liberal Government announced in August 1977 that it would approve the development and export of Australia's uranium. The approval was subject both to stringent environmental requirements and safeguards to prevent the diversion of uranium from peaceful uses. These export arrangements, involving the application of both international and bilateral safeguards (see below) have remained virtually unchanged since, through successive governments.

However, in other respects federal government uranium policy has varied.

In 1983 the new Labor government approved the Nabarlek and Ranger mines which were then operating, and also development of the Olympic Dam mine - hence the so-called "three mines" policy. Proposals for Jabiluka, Koongarra and Yeelirrie were shelved, although in most cases mining, environmental and Aboriginal approvals had been obtained.

In 1984 the Australian Science and Technology Council (ASTEC) Report, on Australia's role in the nuclear fuel cycle, commissioned by the Labor government, recommended not only proceeding with uranium mining but also becoming involved with other stages of the fuel cycle such as enrichment. It also stressed the need for international collaboration in management and disposal of high-level nuclear wastes.

The "three mines" policy was later seen to be illogical and various attempts were made to review it. After the policy became ineffective with Labor in opposition from 1996, it was replaced by a "no new mines" policy, whereby Labor would allow existing and approved uranium mines to continue, but not permit new ones.

In 1996 a Liberal-National Party coalition government came to power and uranium mining was then treated the same as any other mining, except that export controls remained as before, to effect non-proliferation objectives. Although expansion plans for Ranger and Olympic Dam were pending, proposals for new mines were able to be brought forward. In 2000, the new Beverley mine opened.

Government Policy: Canada

In 1944, an engineering design team was brought together in Montreal, Quebec, to develop a heavy water moderated nuclear reactor. The National Research Experimental reactor (NRX) was built at Chalk River, Ontario, and started up in 1947. It provided the basis for Canada's development of the very successful CANDU series of power reactors, and served as one of the most valuable research reactors in the world.

Also in 1944, the federal government took over the Eldorado company (hitherto mining radium) and formed a new Crown corporation which later became Eldorado Nuclear Ltd. Uranium exploration was restricted to the joint efforts of Eldorado and the Geological Survey of Canada until 1947. In the late 1970s the Saskatchewan Mining Development Corporation, a provincial crown corporation, had taken a 20% interest in the Cluff Lake development and a 50% interest in Key Lake. In 1988 this merged with Eldorado Nuclear Ltd to form Cameco Corporation, now the world's leading uranium producer. In 1991 Cameco made its first public share issue.

The Canadian and Saskatchewan governments have adopted a policy of supporting uranium mining where it can be demonstrated to be environmentally acceptable. In 1991 a Joint Federal-Provincial Environmental Assessment and Review Panel was formed to study the health, safety, environmental and socio-economic impacts of five proposed uranium mining developments in northern Saskatchewan. A Federal Panel was formed to examine a sixth proposal. Expansions at the Cluff Lake and Rabbit Lake operations were reviewed and approved in 1993, and came into operation.

Safeguards to Prevent Military Use

Among uranium exporting countries Australia and Canada have some of the strictest conditions relating to the use of its uranium. These safeguards (inspections and accounting procedures) ensure that exported uranium is used for peaceful purposes only and is not diverted for military purposes or used in a way which adds to the proliferation of nuclear weapons.

Agreements to this effect between the Australian and Canadian Governments and each country wishing to import their uranium are therefore necessary before sales contracts can be completed. Such agreements are in addition to the application of International Atomic Energy Agency (IAEA) safeguards administered under the Nuclear Non-Proliferation Treaty.

Australia has in force 14 bilateral nuclear safeguards agreements covering 24 countries - Canada, Egypt, Finland, France, Japan, Republic of Korea, Mexico, Philippines, Russia, Sweden, Switzerland, UK, USA and EURATOM (including Austria, Belgium, Denmark, Germany, Greece, Ireland, Italy, Luxembourg, Netherlands, Portugal and Spain in addition).

The safeguards requirements under these bilateral agreements with Australia, and similar ones with Canada, are additional to those under the Non-Proliferation Treaty. Among other things they permit the reprocessing of used fuel only as part of a recipient country's nuclear energy program that has already been approved by the exporting country. Any reprocessing must be done under IAEA safeguards. The further transfer of nuclear material is only permitted to countries which have bilateral safeguards agreements with Australia or Canada.

Government Regulation of Mining

Since the announcement of the Australian Government's Uranium Policy in 1977, legislation has been passed covering a wide range of matters affecting uranium mining, including health, environment and Aboriginal land rights.

The Environment Protection (Nuclear Codes) Act amended in 1978 provides for the protection of the health and safety of the people and the environment from possible harmful effects associated with nuclear activities. Three codes of practice have therefore been developed by a joint Commonwealth-State Consultative Committee to cover

• Radiation protection in the mining and milling of radioactive ores.
• Management of radioactive wastes from the mining and milling of radioactive ores.
• Transport of radioactive substances.

In Canada similar regulations apply, with the federal government having the main responsibility for licensing and regulation through the Canadian Nuclear Safety Commission. The Saskatchewan government also issues construction approvals and annual permits to operate, and these comprehensive licenses are the basis of the province's regulation.

Australia and Canada are now the world's major producers and exporters of uranium. In addition to providing further diversification and strength to their domestic economies, it gives both countries a voice in the framing of international nuclear policies and safeguards. It also reduces the need for buyers to seek uranium from countries with less effective safeguards.