PERTH (miningweekly.com) – Diversified major BHP Billiton would invest about $200-million in its Olympic Dam operation, in South Australia, as part of its debottlenecking efforts, and would accelerate long-term drilling plans and mine development.

CFO Peter Beaven said on Monday that it was hoped the debottlenecking initiatives would increase total ore production to 11-million tonnes a year and deliver an additional 50 000 t/y of copper from the operation by 2018.

“We have a slightly unbalanced range of capacity at Olympic Dam,” Beaven told journalists in a media call on Monday, saying that the company was currently working to match its surface, smelter, concentrator and milling capacity to the current refinery capacity of 235 000 t/y.

The miner was currently expanding the underground footprint of the Olympic Dam project into the southern mining area, to access higher grade ore, and to increase ore hoisting to 11-million tonnes a year. The move to the southern mining area would also allow for grade recovery to increase and would enable the full use of the smelter and refinery.

Beaven said that while the underground development of the southern mining area would require additional capital above and beyond the $200-million being invested in the debottlenecking efforts, this capital spend was only being brought forward, and was not considered additional capital.

Meanwhile, the miner was also advancing its plans to expand Olympic Dam ore production to about 21-million tonnes a year, allowing for the potential to deliver about 450 000 t/y of copper from the 2024 financial year.

BHP CEO Andrew Mackenzie has previously announced that the miner was investigating heap leaching as an avenue of expanding the Olympic Dam operations, saying it would deliver a lower-cost alternative to extract metals from the underground ore.

Beaven said that the adoption of this technology to expand the Olympic Dam operation would require the support of all stakeholders, including government and the regional community in South Australia.

“Heap leach is not only cheaper from a capital perspective, but also from an operating capital perspective. So if we can make it work, it should be very compelling. But it is still a large project, and it has to compete with capital within BHP,” Beaven noted, adding that gaining capital approval for the project would not be a "slam dunk".