Prospect or suspect – uranium mining in Australia

Key text

Uranium is ubiquitous

Uranium is a naturally occurring radioactive element. While traces of uranium occur almost everywhere on Earth, the highest concentration is found in the Earth's crust. For example, there are about 3 milligrams of uranium per tonne of sea water, and up to 4 grams per tonne of Australian coal. The rocks that are mined for uranium in Australia contain about 3 kilograms of uranium per tonne.

Large amounts of energy are obtained by splitting uranium atoms

Related site: The nuclear fuel cycle Describes the process of uranium mining, enrichment, recycling and used fuel disposal. (Uranium Information Centre, Australia)

Uranium has only become valuable since the explosion of the first atomic bomb in 1945, during World War II. This explosion confirmed the theory that energy could be released by splitting uranium atoms. The amount of energy released is calculated by using Einstein's famous equation, E = mc² .

Uranium is a very high-grade energy source. In practice, about 120,000 tonnes of black coal (350,000 of brown coal) would need to be burnt to get as much energy as could be obtained from 1 tonne of uranium fuel, of which 35 kilograms is fissionable. It takes 140 tonnes of uranium ore to make 27 tonnes of enriched uranium fuel, of which 1 tonne is fissionable.

Electricity can be generated from uranium

Most of the world's mined uranium (and all of Australia's) is used to generate electricity in nuclear power stations. A controlled atomic process produces heat, which converts water to steam to drive the turbines which generate electricity.

Nuclear energy currently provides about 17 per cent of global electrical power, but in France it provides 75 per cent of electricity.

Nuclear power: advantages and disadvantages

Unlike coal-fired power stations, nuclear reactors do not generate carbon dioxide and atmospheric pollution. Every tonne of mined uranium used for fuel in place of coal saves the emission of 40,000 tonnes of carbon dioxide. However, there are disadvantages because of the danger of ionising radiation (Box 1: The danger of ionising radiation) that can come from mining and transporting uranium, accidents, and disposing of nuclear wastes.

Australian uranium is exported

Australia does not generate any nuclear power but does mine and export uranium. Australian mines provide about 22 per cent of the world's uranium, second only to Canada. In 2004-05 Australia produced more than 10,000 tonnes of uranium oxide, generating over $A475 million of export revenue.

Australian uranium goes only to countries that undertake to use it solely for peaceful purposes. Many of these countries have insufficient supplies of coal or hydroelectricity or choose to use nuclear energy because it is more economical and it reduces atmospheric pollution.

The three mines policy restricted uranium mining

In 1984 the federal Labor government introduced their three mines policy. It confined Australia's uranium production to the three sites already being mined: Ranger, Nabarlek and Olympic Dam. At the time, the mining industry felt that this unnecessarily restricted uranium mining.

Present government policy is to allow uranium to be mined and exported

The three mines policy was abandoned when the Coalition government was elected in March 1996. The Coalition's policy is to develop the export potential of Australia's uranium industry by allowing mining and export of uranium under strict international agreements designed to prevent nuclear proliferation.

Today the Ranger mine in the Northern Territory and the Olympic Dam mine in South Australia continue to operate, but the Nabarlek mine has closed. There is now a third uranium mine operating (Beverley), with approval given for a fourth mine (Honeymoon). Both of these mines are in South Australia.

Uranium mining can have an impact on Aboriginal groups

Mining in Australia's remote areas can be controversial when it is carried out in places that have great significance for Aboriginal people. The question of Aboriginal land rights is a complex one. Some areas in many States have now reverted to Aboriginal title, meaning that the Aboriginal people in the area are, as a group, the legal owners of the land, which they may then lease to governments, individuals or corporations.

In September 2002 the company responsible for the Jabiluka mine site in the Northern Territory announced that the mine would not go ahead without the consent of the local Aboriginal people.

Environmental effects of uranium mining

Conservationists point out that the effects of mining can go far beyond the small area disturbed in the operation. A mine cannot operate in isolation. It requires the construction of roads, the transport of material and the disposal of wastes.

Related Nova topic:

Looking for clues to our mineral wealth

Box 1. The danger of ionising radiation

People are exposed to high doses of ionising radiation when nuclear explosions or nuclear accidents occur. High doses of ionising radiation destroy body tissues, and death occurs immediately or soon after exposure. However, the effects of lower doses may not show up for years after exposure and are due to various changes in DNA molecules and chromosomes. There are at least four ways in which low doses of ionising radiation can affect cells:

1. Low doses of ionising radiation can bring about delay in the process of cell division, but the reasons behind this phenomenon are not known.

2. Radiation-induced mutations seem to be brought about by the deletion of small pieces of chromosomes during the process of chromosome breakage and repair, and if such changes occur in egg-producing or sperm-producing cells they may be inherited by the offspring.

3. Ionising radiation can induce the abnormal growths of cells. Advanced cancer cells usually have an abnormal complement of chromosomes, but other smaller genetic changes may also play a part in carcinogenesis. Since chromosome damage is most likely to happen in dividing cells, ionising radiation is most likely to cause cancer in those parts of the body where cells are actively dividing.

4. Ionising radiation kills rapidly dividing cells. This specific effect of ionising radiation can be put to use. Cancer cells produced by human genetic defects or other causes divide rapidly, which is why they are dangerous. Careful application of radiation (radiation therapy) can therefore be used to kill the cancer cells while leaving normal cells relatively undamaged.

As with many public health issues, it is not the increased risk to an individual that is of greatest concern, but rather the effect on the total population. For example, while a change in risk from 0.1 to 0.2 per cent is not a big increase in risk for an individual, the number of people affected in a city of l million would rise from 1000 to 2000, with clear implications for hospital beds and other health facilities.

Related sites

• Radiation and life (Uranium Information Centre)

• How nuclear radiation works (How Stuff Works, USA)

• What we know about radiation (US National Institute of Health)

Activities

• Australian Nuclear Science and Technology Organisation
  • Nuclear science in society – students explore aspects of nuclear science and technology.

• Australian Broadcasting Corporation
  • Nuclear power – students assess alternative sources of energy, how uranium is used to create energy and different points of view about nuclear energy.

• Science upd8, UK
  • Nuclear power: The great debate – students examine the arguments and come to their own conclusions about the benefits and dangers of going nuclear.

• Science NetLinks (American Association for the Advancement of Science)
  • Frosty the snowman meets his demise: An analogy to carbon dating – students use a simple graph to extrapolate data to its starting point.
  • Radioactive decay: A sweet simulation of a half-life – demonstrates that the rates of decay of unstable nuclei can be measured, that the exact time that a certain nucleus will decay cannot be predicted, and that it takes a very large number of nuclei to find the rate of decay.

Activity 1. Graphing the amounts of uranium in different substances

• Draw a histogram to show the amounts of uranium in sea water, granite, coal, and rocks for uranium mining.

Teachers notes

Some students may need help with choosing a suitable scale on the vertical axis. You could introduce the idea of interrupting or breaking a scale to accommodate the range from 1 gram to 7 kilograms.

Activity 2. Uranium, nuclear energy and radioactivity: library research

1. Can the production of nuclear energy be linked with the development of nuclear weapons?

2. Uranium ore is radioactive while it is in the ground, so why are people concerned about the effects of radiation from uranium mining?

Teachers notes

1. Plutonium, produced as a waste product by nuclear reactors, can be used to fuel nuclear weapons.

2. Mining the ore brings the radioactivity to the surface. The process of concentration increases the radiation per kilogram of material. The mining and transport of ore increases the area and number of people that could be exposed to radiation.

Activity 3. The advantages and disadvantages of enriching uranium within Australia

• milling (crushing and grinding);
• leaching (dissolving the uranium and some other metals in sulfuric acid or similar solvent), with remaining solids being pumped to a tailings dam;
• extraction of the dissolved uranium by a precipitation process to produce 'yellow cake' (uranium oxide);
• concentration, where the yellow cake is purified and converted to uranium hexafluoride;
• enrichment, where the proportion of the fissile uranium isotope is increased from about 0.7 to 3 per cent;
• fuel fabrication, where uranium hexafluoride is converted to uranium dioxide and formed into pellets that can be loaded into fuel rods for the use in a reactor.

All these stages can release radioactive gases and dust unless precautions are taken. In addition, the solids left after leaching contain traces of the radioactive material from the original ore, so tailings must be buried.

At present ore mined in Australia is treated at the mine to the end of the extraction stage and uranium is then exported in the form of yellow cake, but some people argue that uranium ore should be enriched in Australia.

• What are the advantages and disadvantages of carrying out enrichment in Australia?

Teachers notes

The following aspects of carrying out enrichment in Australia could be considered.

Advantages:

• creates more employment;
• adds value to the product and so increases the economic return;
• reduces bulk and weight of material to be transported, so reduces transport costs and saves fuel;
• Australia has more suitable sites than most countries in which to store stockpiled wastes.

Disadvantages:

• increases the number of people in Australia who risk exposure to radiation;
• increases the amount of radioactive waste that has to be stored in Australia.

Activity 4. The three mines policy: arguments for and against

• What are the arguments for and against going back to the three mines policy?

Teachers notes

Arguments for going back to the three mines policy could include:

• The hazards to the Australian environment outweigh any potential economic gain.

• Uranium is a non-renewable resource. Perhaps if it is not mined now, it could be more profitable to sell at a higher price in the future when there are more safeguards.

• If Australia were to open more mines, it would increase the supply of uranium. This increased supply might force down the price, and reduce the pressure on society to conserve energy, and to develop other energy sources.

Arguments against could include:

• If Australia forgoes selling some of its uranium because of the three mines policy, other exporting countries will produce more to fill the demand and 'take' the earnings from Australia.

• Other countries selling uranium may not have the same environmental safeguards or restrictions on end-use as we do and the global environment would suffer further damage.

• Greater use of uranium for power production would reduce the emission of deleterious greenhouse gases produced by burning coal and oil.

• Coal-burning power stations release small amounts of radioactive uranium from the burnt coal. Nuclear power stations release no radioactivity into the air (except when accidents occur).

Activity 5. Factors to consider before opening a new mine

• List all the points that an independent assessor would need to investigate. Then describe how the assessor might obtain the information needed for each point listed.

Teachers notes

Factors that need to be taken into account before a new mine is opened include:

• environmental impact;
• sacred sites;
• disposal of wastes;
• transport of products;
• associated commercial development and influx of people;
• how the profits of the mine will be distributed;
• Aboriginal input to decision-making;
• scientific input to decision-making;
• site restoration.

Activity 6. The implications of nuclear-free zones within Australia

1. If the federal government, in making policies for the whole country, decides that uranium mining (and the related transport of materials) is acceptable, should individual municipalities be allowed to interfere with these policies?

2. What would happen if every council in Australia declared its shire or municipality to be a nuclear-free zone?

3. Imagine you live in a municipality that is not a nuclear-free zone and the federal government is proposing to build a transport depot for yellow cake near your town. Write a letter to the minister responsible for the decision, explaining your attitude to the proposal.

Teachers notes

These questions are important as a means of encouraging informed discussion. Students can be encouraged to find answers to questions that arise during their discussion (eg, the amount of risk if a semi-trailer carrying yellow cake loses its load in a traffic accident).

Activity 7. Exporting uranium: a debate

• That Australia should stop exporting uranium so that there will be less risk of nuclear warfare.
• That if Australia wants to export uranium it should do so from deposits other than those in national parks.
• That Australia should continue to export uranium so that the pollution of the atmosphere with carbon dioxide can be reduced.

Teachers notes

Debates are only effective if the participants are well informed on the topic. Encourage students to prepare for a debate by having them individually produce a summary of appropriate facts, or by dividing the class and having half prepare arguments for one side of the topic and half prepare arguments for the other side (either individually or in groups). Alternatively, the debate could be preceded by a discussion of the topic, followed by an opportunity for students to collect information highlighted by the discussion.

Activity 8. Exploring uranium mining issues: a role-play

• Aboriginal elder;
• shop owner in a nearby town;
• economist;
• environmentalist;
• mining company representative;
• grazier;
• government official;
• scientist;
• power station engineer.

Teachers notes

To make the best use of role-play activities:

• have a clear idea of the desired outcomes;
• help students by ensuring that they have adequate information and that they understand the likely attitudes of the people they are representing.

Always leave time at the end of the lesson for debriefing. Debriefing can include questions that help students to distinguish between the simulation and reality, and between their own attitudes and those they acted out during the role play. In addition, you could tell students the desired outcomes and then they could discuss how effective they think the activity was. Debriefing helps to ensure that any antagonisms developed during the role-play do not continue after the lesson.

Further reading

Useful sites

Australia's uranium and who buys it (World Nuclear Association)

Updated in 2004, this article has a brief history of mining and recent (2003-2004) data on Australia's production and export of uranium.
http://www.world-nuclear.org/info/inf48.html

Uranium Information Centre (Australia)

The Uranium Information Centre, set up in 1978, is funded by companies involved in the exploration, mining and export of uranium in Australia. Topics include: 'Australia's uranium mines'; 'What is uranium? How does it work?'; and 'Australia's uranium and who buys it?' There is a great deal of factual and up-to-date information at this site, including a large glossary.
http://www.uic.com.au/

Environmental research and supervision of uranium mining (Australian Government Department of the Environment and Water Resources)

Provides extensive information about the environmental impact of uranium mining in the Northern Territory. For example, click on 'Protecting ecosystems' for information about environmental monitoring programs and on 'Uranium mining in the Alligator Rivers Region' for more detail about Jabiluka, Ranger, Koongarra and Nabarlek.
http://www.ea.gov.au/ssd/uranium-mining/index.html

Uranium mineral fact sheets (Australian Atlas of Mineral Resources, Mines and Processing Centres)

Outlines uranium resources, new mine developments, mining methods and export of Australian uranium.
http://www.australianminesatlas.gov.au/info/factsheets/uranium.jsp

The power and the passion (The Lab, Australian Broadcasting Corporation)

Discusses the renewal of the nuclear power debate.
http://www.abc.net.au/science/features/powerpassion/default.htm

Introduction to: The debate on nuclear policy in Australia, 2005-2006 (by Brian Lloyd, Parliamentary Library Service, Northern Territory Library, Australia)

Examines the arguments presented for and against the expansion of Australia’s nuclear activities.
http://notes.nt.gov.au/dcdsca/intranet.nsf/Files/Debate_on_Nuclear_Policy/$file/
RPPLS_Introduction_Nuclear_Policy_Debate_Brian_Lloyd_No2.pdf

World Nuclear Association (UK)

• Introduction to nuclear energy: Overview
  Provides a simple overview of basic aspects of nuclear energy. There are links from this page to information papers on particular topics (eg, 'Nuclear power reactors' and 'Uranium markets').
  http://www.world-nuclear.org/info/info.html#nuclearpower

• Getting uranium from the ground
  Provides a brief description of mining and processing methods. Other information about fuel conversion and environment, and used fuel management is available http://www.world-nuclear.org/how/how.html.
  http://www.world-nuclear.org/how/mining.html

Glossary

E=mc² . E stands for the energy released, m stands for the mass that is converted into energy, and c is the speed of light (300,000 kilometres per second).

ionising radiation. Any form of radiation that has sufficient energy to remove electrons from atoms, so producing charged particles called ions. It can consist of high energy particles (electrons, protons or alpha particles) or short wavelength electromagnetic radiation (ultraviolet, X-rays and gamma rays).

nuclear fission. Also referred to as atomic fission. The process by which large nuclei are split into two parts, by bombarding them with neutrons, in order to release large amounts of energy.

uranium. A radioactive heavy metal. The natural element is a mixture of different isotopes or atomic forms. The isotope uranium-235 is used in nuclear non-breeder reactors.