Ranger Uranium Mine

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Ranger mine buildings
Ranger mine buildings

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.[1]

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.

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[edit] Ore processing

Ore is ground, then leached with sulfuric acid. 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.[1]

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. [2].

[edit] Environmental issues

Aerial view of the Ranger 3 site located within Kakadu National Park.
Aerial view of the Ranger 3 site located within Kakadu National Park.

Ranger uranium mine, being within the highly respected and iconic Kakadu preserve, and being a uranium mine is highly sensitive politically for its environmental impact upon this wilderness area.

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.[3] The original pit is now being used to store tailings.

Contrary to the recommendations of the Fox Report,[4]neither the tailings dam nor the tailings dump in Pit #1 are isolated by lining, or any other significant physical barrier. As a result the mine site continues to suffer from seepage from these tailings stores of contaminated water which is juggled between the ponds and these tailings dumps.

Due to inadequate estimation of annual rainfall in the design phase, [5] the mine has continued to suffer routine seasonal failure of the water management systems. [6]

A mine closure model has been developed by the company and is provided for in the balance sheet to the value of over AU$180 million.[7] However opponents warn that this may be as little as one fifth of the final cost of rehabilitation. [8] The rehabilitation plan has not been made public, and environmentalists warn that plans for further expansion [9] will further widen the gap between needs and means for remediation of the mine site.[citation needed]

[edit] Safety breaches and controversy

Environment Australia (an agency of the Government of Australia) have documented over 200 environmental incidents since 1979.[6]

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.[10] 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.[11]

Other incidents involving decontamination of vehicles have been identified.[11] 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.[12]

Another significant controversy over Ranger's environmental impact is the public legal confrontation over releases into Magella 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, demonstrating how powerless the miner is against the very real possibility of a direct hit.

[edit] See also

[edit] References

  1. ^ a b Ranger. Australia's Uranium Mines. Uranium Information Centre (October 2006). Retrieved on 2007-01-15.
  2. ^ ERA APPROVES LATERITE PROCESSING PLANT. ASX announcement. Energy Resources of Australia (29 November 2006). Retrieved on 2007-01-16.
  3. ^ Current Practices for the Management of Uranium Mill Tailings. Technical Report Series No. 335, IAEA, Vienna 1992
  4. ^ Ranger Uranium Environmental Inquiry - Second Report, Mr Justice Fox, 1977
  5. ^ Mining at Ranger. Sustainable Energy and Anti-Uranium Service (30th November 1997).
  6. ^ a b Regulating the Ranger, Jabiluka, Beverly and Honeymoon uranium mines - Appendix 6. Senate Environment, Communications, Information Technology and the Arts Committee (14 October 2003).
  7. ^ 2005 Annual Report pages 15-16 and 55. Energy Resources of Australia (February 2006). Retrieved on 2007-01-16. “The company’s obligations in respect of mine closure are clearly rticulated in the Ranger authorisation, and each year an amended plan of rehabilitation, backed by a fund held by the Commonwealth Government, is approved by regulators and stakeholders to cover immediate closure of the site. In 2005 the company went further by creating, a draft ‘first pass’ closure model which seeks to define the work required to close and rehabilitate the Ranger site upon final cessation of mining.”
  8. ^ No to Howard's nuclear madness. Green Left Weekly (24 November 2006).
  9. ^ Mandi Zonneveldt (16 January 2007). Uranium miner expands. the Courier Mail. Retrieved on 2007-01-17.
  10. ^ John Carroll v Energy Resources of Australia [2005] NTMC 067
  11. ^ a b Contamination incidents at Ranger mine. Department of the Environment and Heritage annual report 2004-05. Australian Department of the Environment and Heritage (2005). Retrieved on 2007-01-15.
  12. ^ "ERA fined $150,000 over contamination", The Age, June 1, 2005. Retrieved on 2007-01-15. 

[edit] External links

Coordinates: 12°41′S, 132°55′E