18 June 2019
BHP has successfully completed its heap leach research and development trial in South Australia, confirming the viability of the technology to extract copper, uranium, gold and silver at Olympic Dam.
The program began in 2012 and was conducted at a purpose-built, small-scale heap leach facility at Wingfield run by Bureau Veritas, under direction from BHP and with support from the South Australian Government.
BHP’s General Manager of Olympic Dam’s surface processing, Chris Barnesby, made the announcement at the Copper to the World conference in Adelaide today (18 June).
‘The promising results from this trial supports our positive outlook for Olympic Dam, given forecast demand increases for copper and the optionality we are building for this world-scale resource,' Ms Barnesby said.
‘We safely and successfully produced 19 tonnes of good quality copper, most of which went back into the smelter and off to customers, though we kept a little to ourselves to commemorate the achievement.
‘Whether we deploy heap leach at Olympic Dam is a matter for future consideration, as there are many factors involved including passing through our Capital Allocation Framework.
‘As it stands today, we have confirmed the viability of a technology with the potential to join our suite of growth options. However, our immediate focus is on operating safely and reliably, and setting a foundation to unlock more value for BHP and for South Australia over the long term.’
Heap leaching works by drip-feeding acid through a large stockpile (or heap) of ore to leach out metals. BHP uses heap leaching at its copper operations in Chile, however Olympic Dam’s polymetallic properties require a different approach.
The research and development program has the potential to benefit the mining industry more broadly in South Australia, as heap leaching has the potential to deliver lower capital and operating costs, increased scalability, reduced potable water use and the ability to process lower-grade ores.
Separate to the trial, BHP continues to progress studies the Brownfield Expansion Project, or BFX, as part of Olympic Dam’s resource development strategy which seeks to potentially increase production to between 240 and 300 kilotonnes per annum.