Ranger Uranium Mine
Encyclopedia
The Ranger uranium mine is surrounded by Kakadu National Park
, in the Northern Territory
of Australia
, 230 km east of Darwin
. The orebody was discovered in 1969, and the mine commenced operation in 1980, reaching full production of uranium oxide
in 1981. It is operated by Energy Resources of Australia
, a 68% subsidiary of Rio Tinto Group
.
Uranium mined at Ranger is sold for use in nuclear power stations in Japan, South Korea, UK, France, Germany, Spain, Sweden and the United States.
The original orebody was completely mined out by the end of 1995, although some ore remains stockpiled. A second orebody ("Ranger 3") began mining in 1997. Both have been open-pit
mines.
The orebody was discovered in 1969, and the mine commenced operation in 1980, reaching full production of uranium oxide
in 1981.
Owing to the environmental sensitivity of the site, a special statutory authority, the Supervising Scientist
, was created to provide oversight of the operation and conduct environmental research in the region.
The Ranger Uranium Mine covers two of a line of uranium orebodies that extend from near Nourlangie Rock in Kakadu north-eastwards to Koongarra, underneath Mount Brockman, then northwards through the Ranger One line of orebodies (in order Number 2, Number 1, and Number 3), then via Hades Flat, where there is uranium mineralisation, to Jabiluka where the line turns westward through the Barote and Ranger 4 orebodies. The mine covers No 1 Orebody and No 3 Orebody. No 2 orebody was excluded from the mining lease at the request of the traditional owners and included in Kakadu National Park. From Ranger 4 the line again turns northwards and then swings westward round an Archaean basement dome before turning south towards Nourlangie Rock again. Uranium mineralisation is known at several other places along this line but has never been explored in detail because of the creation of Kakadu. The name 'Ranger' for the series of discoveries made by Geopeko Limited, the exploration arm of the Australian mining company Peko-Wallsend Limited, in the period 1969 to 1972, was thought up by Judy Ryan, the wife of the geologist in charge of the program. Koongarra and Jabiluka were retained by the companies that found them: Noranda Australia and Pancontinental Mining respectively, although since sold to other parties. The other discoveries are enclosed in the National Park, locking up an energy source that is estimated to be greater than the oil reserves of Saudi Arabia. (12)
. Uranium is removed using kerosene
with amine
then stripped with ammonium sulfate
solution and gaseous ammonia
. Ammonium diuranate
is precipitated by increased pH
and converted to uranium oxide (U3O8) in a furnace.
In early 2006, ERA announced an expansion to the ore processing plant which will allow production to extend into lower-grade material and in November 2006 the company announced plans to invest in a laterite
processing plant, which will allow it to process ore with a high clay content that has been stockpiled since the mine began operating. This ore had been already included in stated reserves. The laterite processing plant will contribute 400 tonnes of uranium oxide per year from 2008 until 2014.
Due to inadequate estimation of annual rainfall in the design phase,
the mine has continued to suffer routine seasonal failure of the water management systems.
A mine closure model has been developed by the company and is provided for in the balance sheet to the value of over A$
180 million. However opponents warn that this may be as little as one fifth of the final cost of rehabilitation.
The rehabilitation plan has not been made public, and environmentalists warn that plans for further expansion
will further widen the gap between needs and means for remediation of the mine site.
) have documented over 200 environmental incidents since 1979.
In May 2005, the company was convicted for breaching environmental guidelines - the first such prosecution of a mining company in the Northern Territory, relating to accidental radiological exposure to ERA employees. Radiologically contaminated process water had contaminated the drinking water supply and some workers drank and washed in the contaminated water. The maximum radiation exposure of workers was likely to have been much less than the regulatory limit, and no harmful long-term health effects are likely.
Other incidents involving decontamination of vehicles have been identified. When the work-for-welfare mechanic in Jabiru
opened the engine bay, he was unaware of the nature of the mud and dirt which fell on the floor. The court heard that in the following weeks, after he had swept the material outside his shed, his children played and built sandcastles in mud contaminated with uranium.
Another significant controversy over Ranger's environmental impact is the public legal confrontation over releases into Magela Creek in the 1995 wet season. More recently, the ARRAC report from 2002 details a major leak of about 2 megalitres of potentially polluted water, over a number of months.
In 2007, water breached a retention pond, overflowing back into the pit. The original authorisation required that this water be contained at all times. In 2006, water management systems were knocked into disarray by Cyclone Monica
.
In May 2010, it was reported that a tailings dam may have released millions of litres of radioactive water into world heritage-listed wetlands in Kakadu National Park
, home to about 500 Aboriginal people.
Kakadu National Park
Kakadu National Park is in the Northern Territory of Australia, 171 km southeast of Darwin.Kakadu National Park is located within the Alligator Rivers Region of the Northern Territory of Australia. It covers an area of , extending nearly 200 kilometres from north to south and over 100 kilometres...
, in the Northern Territory
Northern Territory
The Northern Territory is a federal territory of Australia, occupying much of the centre of the mainland continent, as well as the central northern regions...
of Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, 230 km east of Darwin
Darwin, Northern Territory
Darwin is the capital city of the Northern Territory, Australia. Situated on the Timor Sea, Darwin has a population of 127,500, making it by far the largest and most populated city in the sparsely populated Northern Territory, but the least populous of all Australia's capital cities...
. The orebody was discovered in 1969, and the mine commenced operation in 1980, reaching full production of uranium oxide
Uranium oxide
Uranium oxide is an oxide of the element uranium.The metal uranium forms several oxides:* Uranium dioxide or uranium oxide * Uranium trioxide or uranium oxide...
in 1981. It is operated by Energy Resources of Australia
Energy Resources of Australia
Energy Resources of Australia Ltd is a public company based in Australia. It is a subsidiary of the Rio Tinto Group which owns 68.4% of the company. The chairman is David Klingner and chief executive officer is Harry Kenyon-Slaney....
, a 68% subsidiary of Rio Tinto Group
Rio Tinto Group
The Rio Tinto Group is a diversified, British-Australian, multinational mining and resources group with headquarters in London and Melbourne. The company was founded in 1873, when a multinational consortium of investors purchased a mine complex on the Rio Tinto river, in Huelva, Spain from the...
.
Uranium mined at Ranger is sold for use in nuclear power stations in Japan, South Korea, UK, France, Germany, Spain, Sweden and the United States.
The original orebody was completely mined out by the end of 1995, although some ore remains stockpiled. A second orebody ("Ranger 3") began mining in 1997. Both have been open-pit
Open-pit mining
Open-pit mining or opencast mining refers to a method of extracting rock or minerals from the earth by their removal from an open pit or borrow....
mines.
Discovery and operation of the mine
Uranium oxide
Uranium oxide is an oxide of the element uranium.The metal uranium forms several oxides:* Uranium dioxide or uranium oxide * Uranium trioxide or uranium oxide...
in 1981.
Owing to the environmental sensitivity of the site, a special statutory authority, the Supervising Scientist
Supervising Scientist
The Supervising Scientist is a statutory office under Australian law, originally created to assist in the monitoring of what was then one of the world's largest uranium mines, the Ranger Uranium Mine...
, was created to provide oversight of the operation and conduct environmental research in the region.
The Ranger Uranium Mine covers two of a line of uranium orebodies that extend from near Nourlangie Rock in Kakadu north-eastwards to Koongarra, underneath Mount Brockman, then northwards through the Ranger One line of orebodies (in order Number 2, Number 1, and Number 3), then via Hades Flat, where there is uranium mineralisation, to Jabiluka where the line turns westward through the Barote and Ranger 4 orebodies. The mine covers No 1 Orebody and No 3 Orebody. No 2 orebody was excluded from the mining lease at the request of the traditional owners and included in Kakadu National Park. From Ranger 4 the line again turns northwards and then swings westward round an Archaean basement dome before turning south towards Nourlangie Rock again. Uranium mineralisation is known at several other places along this line but has never been explored in detail because of the creation of Kakadu. The name 'Ranger' for the series of discoveries made by Geopeko Limited, the exploration arm of the Australian mining company Peko-Wallsend Limited, in the period 1969 to 1972, was thought up by Judy Ryan, the wife of the geologist in charge of the program. Koongarra and Jabiluka were retained by the companies that found them: Noranda Australia and Pancontinental Mining respectively, although since sold to other parties. The other discoveries are enclosed in the National Park, locking up an energy source that is estimated to be greater than the oil reserves of Saudi Arabia. (12)
Ore processing
Ore is ground, then leached with sulfuric acidSulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
. Uranium is removed using kerosene
Kerosene
Kerosene, sometimes spelled kerosine in scientific and industrial usage, also known as paraffin or paraffin oil in the United Kingdom, Hong Kong, Ireland and South Africa, is a combustible hydrocarbon liquid. The name is derived from Greek keros...
with amine
Amine
Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines,...
then stripped with ammonium sulfate
Ammonium sulfate
Ammonium sulfate , 2SO4, is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer. It contains 21% nitrogen as ammonium cations, and 24% sulfur as sulfate anions...
solution and gaseous ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
. Ammonium diuranate
Ammonium diuranate
Ammonium diuranate or ' , is one of the intermediate chemical forms of uranium produced during yellowcake production. The name 'yellowcake' originally given to this bright yellow substance, now applies to mixtures of uranium oxides which are actually hardly ever yellow...
is precipitated by increased pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
and converted to uranium oxide (U3O8) in a furnace.
In early 2006, ERA announced an expansion to the ore processing plant which will allow production to extend into lower-grade material and in November 2006 the company announced plans to invest in a laterite
Laterite
Laterites are soil types rich in iron and aluminium, formed in hot and wet tropical areas. Nearly all laterites are rusty-red because of iron oxides. They develop by intensive and long-lasting weathering of the underlying parent rock...
processing plant, which will allow it to process ore with a high clay content that has been stockpiled since the mine began operating. This ore had been already included in stated reserves. The laterite processing plant will contribute 400 tonnes of uranium oxide per year from 2008 until 2014.
Environmental issues
The main long-term environmental impact of uranium mining is that posed by the large volumes of tailings, mining waste in the form of particularised sand, which remain on the minesite. Guidelines from the International Atomic Energy Agency describe the project area as particularly unsuitable for tailings storage. The original pit is now being used to store tailings.Due to inadequate estimation of annual rainfall in the design phase,
the mine has continued to suffer routine seasonal failure of the water management systems.
A mine closure model has been developed by the company and is provided for in the balance sheet to the value of over A$
Australian dollar
The Australian dollar is the currency of the Commonwealth of Australia, including Christmas Island, Cocos Islands, and Norfolk Island, as well as the independent Pacific Island states of Kiribati, Nauru and Tuvalu...
180 million. However opponents warn that this may be as little as one fifth of the final cost of rehabilitation.
The rehabilitation plan has not been made public, and environmentalists warn that plans for further expansion
will further widen the gap between needs and means for remediation of the mine site.
Safety breaches and controversy
Environment Australia (an agency of the Government of AustraliaGovernment of Australia
The Commonwealth of Australia is a federal constitutional monarchy under a parliamentary democracy. The Commonwealth of Australia was formed in 1901 as a result of an agreement among six self-governing British colonies, which became the six states...
) have documented over 200 environmental incidents since 1979.
In May 2005, the company was convicted for breaching environmental guidelines - the first such prosecution of a mining company in the Northern Territory, relating to accidental radiological exposure to ERA employees. Radiologically contaminated process water had contaminated the drinking water supply and some workers drank and washed in the contaminated water. The maximum radiation exposure of workers was likely to have been much less than the regulatory limit, and no harmful long-term health effects are likely.
Other incidents involving decontamination of vehicles have been identified. When the work-for-welfare mechanic in Jabiru
Jabiru, Northern Territory
Jabiru is a town in the Northern Territory of Australia. It was originally built in 1982 as a closed town to house the community living at Jabiru East near the Ranger Uranium Mine eight kilometres away. Both the mine and the town are completely surrounded by Kakadu National Park.- Overview :Jabiru...
opened the engine bay, he was unaware of the nature of the mud and dirt which fell on the floor. The court heard that in the following weeks, after he had swept the material outside his shed, his children played and built sandcastles in mud contaminated with uranium.
Another significant controversy over Ranger's environmental impact is the public legal confrontation over releases into Magela Creek in the 1995 wet season. More recently, the ARRAC report from 2002 details a major leak of about 2 megalitres of potentially polluted water, over a number of months.
In 2007, water breached a retention pond, overflowing back into the pit. The original authorisation required that this water be contained at all times. In 2006, water management systems were knocked into disarray by Cyclone Monica
Cyclone Monica
Severe Tropical Cyclone Monica was the most intense tropical cyclone, in terms of maximum sustained winds, on record to impact Australia. The 17th storm of the 2005–06 Australian region cyclone season, Monica originated from an area of low pressure off the coast of Papua New Guinea on 16 April...
.
In May 2010, it was reported that a tailings dam may have released millions of litres of radioactive water into world heritage-listed wetlands in Kakadu National Park
Kakadu National Park
Kakadu National Park is in the Northern Territory of Australia, 171 km southeast of Darwin.Kakadu National Park is located within the Alligator Rivers Region of the Northern Territory of Australia. It covers an area of , extending nearly 200 kilometres from north to south and over 100 kilometres...
, home to about 500 Aboriginal people.
See also
- McArthur River uranium mine in the Athabasca BasinAthabasca BasinThis article is about the uranium mining region near Lake Athabasca. Not to be confused with the drainage basin of the Athabasca River.The Athabasca Basin is a region of Northern Saskatchewan and Alberta Canada that is best known as the world's leading source of high grade uranium...
in SaskatchewanSaskatchewanSaskatchewan is a prairie province in Canada, which has an area of . Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota....
CanadaCanadaCanada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean... - List of uranium mines
- Unconformity uranium deposits
- Uranium miningUranium miningUranium mining is the process of extraction of uranium ore from the ground. The worldwide production of uranium in 2009 amounted to 50,572 tonnes, of which 27% was mined in Kazakhstan. Kazakhstan, Canada, and Australia are the top three producers and together account for 63% of world uranium...
- Uranium marketUranium marketThe uranium market, like all commodity markets, has a history of volatility, moving not only with the standard forces of supply and demand, but also to whims of geopolitics. It has also evolved particularities of its own in response to the unique nature and use of this material.The only significant...
- Uranium mining in AustraliaUranium mining in AustraliaRadioactive ores were first extracted at Radium Hill in 1906, and Mount Painter in South Australia in the 1930s, to recover radium for medical use. Several hundred kilograms of uranium were also produced....
- Russell Walter FoxRussell Walter FoxRussell Walter Fox AC QC LLB is an Australian author, educator, jurist and former chief judge of the Supreme Court of the Australian Capital Territory. He is best known for his extensive report on uranium mining in Australia in the early 1980s....