A proposed expansion of Olympic Dam mine in South Australia has received approval under federal environmental law, Environment Minister Tony Burke announced today.

Mr Burke said following a rigorous assessment he had approved BHP Billiton's proposed project to expand the Olympic Dam mine under the Environment Protection and Biodiversity Conservation Act, with strict conditions during operation and well beyond the life of the mine.

BHP Billiton will be required to adhere to more than 100 stringent conditions including establishing an offset area of about 140,000 hectares, biodiversity conservation and environment protection management programs and a comprehensive compliance strategy.

The proposal was subjected to independent expert reviews including by Geoscience Australia, the Australian Radiation Protection and Nuclear Safety Agency, and the Supervising Scientist.

"My decision is based on a thorough and rigorous assessment of the proposed Olympic Dam mine expansion including independent expert reviews and consideration of public comments received on the project's environmental impact statement," Mr Burke said.

"These reviews made recommendations to ensure that the proposal meets world best-practice environmental standards for uranium mining and ensure management of native species and groundwater resources.

"While I have considered the economic and jobs benefits of this project, my focus has been on protecting matters of national environmental significance.

"The strict conditions I've imposed will help ensure protection of the natural environment, including native species, groundwater and vegetation, for the long-term.

"With these conditions I am confident the Olympic Dam mine can progress in accordance with world best-practice in environmental protection and management."

BHP Billiton proposes to expand its copper and uranium mining and processing operations at Olympic Dam in northern South Australia.

Under the expansion, BHP Billiton proposes a new open pit mine to lift ore production and new and expanded infrastructure including a waste rock storage facility and an expanded tailings storage facility which would operate simultaneously with the existing underground mine.

BHP Billiton projects that the proposed expansion would create more than 13,000 jobs and contribute over $45 billion to the economy in South Australia and nationally over the next 30 years.

"The conditions apply to all parts of the project, including the proposed desalination plant in the Upper Spencer Gulf, and will ensure that the gulf and its marine life—including the giant cuttlefish—are protected," Mr Burke said.

"BHP Billiton must provide a huge offset area of about 140,000 hectares—eight times the projected clearing associated with the project.

"The company must contribute to biodiversity conservation priorities, landscape scale linkages, the protection and recovery of threatened species, and programs for environmental research.

"When the mine is closed, BHP Billiton must cover the tailings storage facility to protect the environment in the very long term, including from erosion.

"The measures that the company will use to achieve these requirements must all be detailed in an extensive and thorough environmental protection management program, which I must be satisfied with and approve before substantial works on the project can begin.

"The program must describe how compliance with conditions will be achieved, and what action will be taken if conservative thresholds are exceeded. The company will be held accountable if it doesn't comply with the strict approval conditions.

"Ongoing monitoring will ensure that any issue can be tackled immediately, and the program must be reviewed every three years to ensure it remains effective over time, and takes account of the latest scientific information."

Mr Burke said the Australian, South Australian and Northern Territory governments had worked together to share expertise and ensure conditions provided a high level of environmental protection.

For more information go to www.environment.gov.au/epbc.