BHP BILLITON plans to store radioactive mine tailings from its proposed Olympic Dam expansion on the surface, rather than return the material to the pit as the Northern Territory's Ranger uranium mine is required to do, a key environmental group says.
Australian Conservation Foundation nuclear-free campaigner David Noonan said yesterday the company's plan, coming on the eve of the public release of the 3750-page draft environmental impact statement for the expansion, could see the company create the world's largest radioactive tailings pile over the life of the mine.
"I understand the BHP EIS will set out the company plan to accumulate and store the radioactive mine tailings on the surface and to leave those tailings on the surface in perpetuity," he said.
"BHP have told me that what they intend to do with their tailings is not put it back into the pit."
A company spokesman said yesterday he could not comment on the contents of the EIS.
BHP Billiton proposes to turn its Olympic Dam copper, gold and uranium mine, 560km north of Adelaide, from an underground mine into an open-cut operation.
Mr Noonan said the BHP plan would be in contrast to existing regulations governing the Ranger mine and a Labor Party pledge before the last election to follow world best practice for uranium mining.
He said tailings, the waste product of mining operations, at Ranger are required to be returned to the pit at the end of the mine's life, expected to be 2021, and then steps taken to ensure the tailings did not have a detrimental impact on the environment for at least 10,000 years.
According to figures publicly available, Mr Noonan said the proposed expansion of Olympic Dam would produce 70 million tonnes of radioactive mine tailings each year, significantly more than the 10 million tonnes of radioactive tailings now produced each year.
"If they're simply left at the surface, that material would be prone to erosion and spread into the environment," he said.
BHP Billiton stores its tailings above ground at Olympic Dam.
Mr Noonan said the ACF expected the commonwealth to require BHP Billiton to return the radioactive tailings from the expanded Olympic Dam to the pit.
"We'd expect the commonwealth to set at least the same standard (as the Ranger mine) to isolate tailings from the environment for 10,000 years and expect BHP to say through the EIS how to isolate those tailings for 10,000 years to prevent detrimental environmental impacts," he said.
Mr Noonan said the mine tailings were a cocktail of radioactive elements and heavy metals, which have been processed to the consistency of powder.
"Why should the Big Australian be given a special dispensation to dispose of their radioactive tailings and leave it as a hazard for all future generations," he said.
A BHP Billiton spokesman said: "We have been operating safely for 20 years.
"Tailings contain extremely low levels of radiation and they are stored in accordance with very strict licensing conditions and fully regulated by the Environmental Protection Authority."