Disaster: A truck and crane are swamped by acid slurry. All personnel were evacuated before the tank burst. Photo: Gundjeihmi Aboriginal Corporation
It began as a 10-centimetre tear in a leach tank at Ranger uranium mine, in Kakadu National Park. Within an hour it turned into what some are calling one of the worst radioactive accidents in Australia's history.
''It's a massive failure,'' said Justin O'Brien, chief executive of the Gundjeihmi Aboriginal Corporation, which represents the local Mirarr people. ''It's hillbilly mining, and it's not good enough.''
About 12.30am on Saturday morning, mine staff noticed liquid squirting from a crack in Leach Tank 1, a large above-ground tank containing more than 1.4 million litres of highly acidic radioactive slurry. Using a crane, they attempted to cover the crack with a steel plate, before noticing a second hole.
Community response: "It's hillbilly mining, and it's not good enough". Photo: Glenn Campbell
All personnel were then evacuated, shortly after which the tank burst, spilling more than 1 million litres of mud, water, sulphuric acid and radioactive liquid. Such was the force and volume of the spill that the crane was damaged and pushed back a metre. It is understood the radioactive liquid then flowed outside the ''bunded area'', or nearby containment banks, onto grassed areas and into the mine's stormwater and drainage system.
The mine's operator, Energy Resources Australia, said no one was hurt, and that ''multiple containment systems'' prevented the spill having any impact on the Kakadu National Park. ''All water monitoring points have reported normal readings,'' the company said.
But locals are not so sure. ''They can claim that the stormwater system is not connected to the environment,'' Mr O'Brien said. ''But they need to demonstrate that to us beyond reasonable doubt, because we have lost trust.''
Alarm: About 60 Mirarr people live at Mudginberri, on Magela Creek. Photo: Glenn Campbell
About 60 Mirarr people live at Mudginberri, on Magela Creek, just seven kilometres downstream from the mine. ''It's the wet now; it rains every day,'' Mr O'Brien said. ''That creek is flowing right past the mine and into the community, where they fish and hunt, get barramundi, catfish, mussels. They drink the water. They play in it. People are worried sick.''
The spill is the latest of more than 120 incidents at Ranger, which has been mining and processing uranium for more than 30 years. In March 2004, 28 Ranger workers were found to have drunk and showered in water containing 400 times the legal limit of uranium. Later, an excavator covered in radioactive mud was taken to the town of Jabiru for cleaning, contaminating a mechanic and his children. The Howard government threatened to shut the mine after a Senate committee inquiry found a ''persistent pattern of under-performance and non-compliance''.
This year there has been the theft of a vehicle from the controlled radiological area, and the disappearance of four 44-gallon drums of a type used to store yellowcake. (They later turned up in bushland south of Darwin, having been gifted to a Ranger employee. The company claims the drums had received a radiation release certificate.)
''ERA has form with this,'' said Gavin Mudd, of the Mining Policy Institute, who also consults to the Gundjeihmi Aboriginal Corporation. ''The company has a history of delaying infrastructure maintenance in order to maximise profits.''
ERA has been under enormous financial pressure, because of a drop in uranium prices post-Fukushima, and last year's cessation of open-cut mining. The company trumpets its new $220 million brine concentrator which came online this September. But some observers say it has been too little, too late.
''It comes down to regulation,'' Mr O'Brien said. ''They are too close to the regulators, both state and federal … they have the same dry technical 'whitefellas know best' attitude. What we need is robust independent oversight. We simply cannot trust a pack of hillbillies who have been consistently found wanting in regard to safety.''
Environment Minister Greg Hunt said government officials have already been on site. ''It is unacceptable. It is something on which we have taken immediate action in terms of instructing the Supervising Scientists Office to attend, commanding there be an investigation and instructing that there be an immediate clean-up.''