Sunday, July 25, 2010

Issues at Operating Uranium Mines and Mills - Ranger, Australia

Flooded Ranger Uranium Pit

(last updated 12 Jun 2010)
Ranger (Northern Territory)

Traditional Owners of Ranger uranium mine site alarmed by new spills into Kakadu National Park, call into question mine expansion project

Millions of litres of radioactive water from the Ranger uranium mine have flowed into internationally acclaimed and World Heritage-listed wetlands in Kakadu National Park. Traditional owners say they will oppose plans for a huge expansion of the 30-year-old mine by Energy Resources of Australia, unless the company upgrades outdated environmental protection procedures.

The Rio Tinto-owned ERA has tried to play down an alarming and unexplained spike in contamination in water flowing from the mine into Kakadu's Magela Creek between April 9 and 11, 2010, The Age can reveal. About 40 Aborigines live downstream from a site where a measure probe recorded up to five times the warning level of electrical conductivity, which is a measure of contaminants including uranium, sulphate and radium.

Environmental group Environment Centre Northern Territory has been shown evidence showing the spike, which ERA representatives said had originated upstream from the mine and was not ERA's fault.

But, asked about the contamination, ERA admitted the source ''could not be determined and investigations are continuing''. ''It is possible that these have come from the Ranger operations,'' it said. ERA's handling of the spike and other environmental concerns about the mine have strained its relations with the Gundjeihmi Aboriginal Corporation, which represents the Mirarr traditional owners.

In another unreported mishap at the mine, in December 2009 a poorly engineered dam collapsed, spilling 6 million litres of radioactive water into the Gulungul Creek, which flows into Kakadu.

Justin O'Brien, the Gundjeihmi corporation's executive officer, said unless the company changes its environmental procedures, the Mirarr will not support any expansion of the mine - that includes a heap leaching plant, a tunnel under flood-plains, a 1000-person accommodation village, 650 evaporation ponds and a one-square-kilometre tailings dam. The expansion, costing hundreds of millions of dollars, would extend the mine's operation to at least 2021. (The Age May 24, 2010)

The head of the Supervising Scientist Division, Alan Hughes, said his own monitoring showed the recently revealed spikes were magnesium sulphate and no other contaminants of note. (Sydney Morning Herald May 26, 2010)

He said there was a spike in salinity levels because run-off water from a retention pond had spilled into a billabong connected to the creek, but no significant uranium was detected in the water. "(ABC May 27, 2010)

The company that operates the Ranger uranium mine has confirmed higher-than-normal salt levels in a creek in Kakadu National Park is a result of its operations. Energy Resources of Australia (ERA) has investigated two salinity spikes in Magela Creek downstream of the mine in April. Chief executive Rob Atkinson says run-off water from the mine had flowed into the creek. (ABC June 12, 2010)

Uranium concentrations in tailings seepage at Ranger uranium mine 5400 times background; rehabilitation impossible

Contaminated water seeping from the Ranger uranium mine in Kakadu National Park has a uranium concentration more than 5,000 times the normal level, a Senate estimates committee has heard.

The Office of the Supervising Scientist today told the committee that water seeping from underneath the dam has about 5,400 times the level of uranium than the natural background level. Greens Senator Scott Ludlam says the environmental regulator told the committee about 100,000 litres of water seeps from the tailings dam every day. Mr Ludlam says the water has been leaking from the dam for years. He says the regulator says it will be impossible to rehabilitate the site.

"The uranium concentation in the billabong surrounding the mine are about three to five parts per billion," he said. "But the uranium in the processed water that is leaking from beneath the tailings dam is 27,000 parts per billion. So it's roughly 5,500 times as much uramium in that water as there is the surrounding environment and that means the company has got a huge problem." (ABC Feb. 9, 2010)

The reported uranium concentration in the seepage (equiv. to 27 mg/l) is slighthly higher than that to be used for a uranium byproduct recovery project in the Talvivaara nickel/zinc mine in Finland - conincidentally announced the same day. Maybe, ERA should contract this company to deal with this seepage...
> Download Transcript of Environment, Communications, and the Arts Committee, Feb. 9, 2010 (PDF)

Preliminary results of probe into tailings leak at Ranger uranium mine not made public

The Commonwealth supervising scientist of the Ranger uranium mine at Kakadu National Park says investigations are continuing into water contamination at the site. Alan Hughes has told a Senate estimates committee that Energy Resources of Australia has conducted geophysical surveys to determine the impact and extent of leaking from a tailings dam at the mine. Mr Hughes says the company has only preliminary results from the surveys and is not sure if ERA will make the findings public. Greens Senator Scott Ludlam is demanding the report be made public as soon as possible. (ABC Oct. 20, 2009)
> Download Transcript of Environment, Communications, and the Arts Committee, Oct. 20, 2009 (1.1M PDF)

Pit wall instability causes interruptions to operations at Ranger mine

In the September 2009 quarter, "total material mined was 4 percent lower than the June 2009 quarter due to some intermittent interruptions to operations to allow increased surveillance of a known and localised area of instability on the southern wall of the pit." (ERA September 2009 Quarter Operations Review, Oct. 14, 2009)

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