A major expansion of BHP's Olympic Dam mine is a step closer, with the South Australian Government declaring it a major development proposal.
The expansion would increase the mine's copper production by 75 per cent and employ a workforce of 1,800 during the construction phase.
The State Government said the $3 billion proposal would increase Olympic Dam's annual copper production from 200,000 tonnes to up to 350,000 tonnes and increase its level of gold, silver and uranium production.
But Mining Minister Dan van Holst Pellekaan said while it was an exciting prospect, BHP hadn't yet submitted its formal proposal, and still needed to pass a series of environmental, social and economic tests.
"I need to stress that while the Government has given major project status to BHP's proposal, BHP are yet to submit their formal application for this expansion so we await all of that information," he said.
"Very importantly, our government will assess every aspect of their proposal incredibly thoroughly. All potential environmental impacts, potential social impacts, potential economic impacts will be considered incredibly thoroughly.
"A large increase by world standards, 1,800 jobs during construction, 600 additional permanent jobs operation-wise after the construction phase is over.
"This is a very big step out that's proposed but of course it needs to be considered carefully and thoroughly to make sure it's in the best interest of South Australians."
Olympic Dam is located about 560 kilometres north of Adelaide and is one of the world's largest mines, employing about 3,500 people in South Australia.
'World-class resource' for the state
Plans for a $30 billion redevelopment of the copper and uranium mine were shelved in 2012, and with it the hopes of a massive economic windfall for South Australia.
But the company said today's declaration by the State Government was the first step in a comprehensive process of getting an expansion project off the ground.
BHP Billiton's Olympic Dam asset president Laura Tyler said the company was aiming to achieve stable and sustainable growth at Olympic Dam.
"Olympic Dam is a world-class resource with the potential to deliver value to BHP and South Australia for many decades to come, especially given our positive outlook for global copper demand," she said.
"We are pleased the South Australian Government has declared Olympic Dam's growth plans a major development, recognising our significance to the state."
The company said it would seek board approval for the project by mid-to-late 2020.
