Crushed ore cone at Nolans processing plant. Image: Resolute Mining. Photography: Roslyn Budd.
BY AMY BLOM
DESPITE almost closing Ravenswood mine in 2016, Resolute Mining has now announced a 14-year mine life with staged plans to return to 5 million tonne per annum open cut mining. Along with Ravenswood, its operations in Africa and a dedication to increasing output through new technology, Resolute expects to grow annual production to 500,000 ounces by 2021.
Innovation and experience was the key to successfully extending the life of the Ravenswood mine in QLD, according to Resolute Mining chief executive and managing director John Welborn.
Just over two years ago, the Ravenswood gold operations were hanging in the balance, with the Mt Wright deposit expected to close in mid-2016 due to depleted resources.
Resolute has since been able to extend the mine life at Ravenswood to 2032 by going against the grain and transitioning away from underground mining to open pit mining.
Mr Welborn told The Australian Mining Review the move meant Resolute had found its way out of an uncertain time at Ravenswood, which is about 95km south west of Townsville and 65km east of Charters Towers.
“It’s somewhat counter-intuitive because most mines go from open cut to underground as you get deeper and you exploit the service material and then chase the ore body deeper, which is what we’re doing at Syama, our main operation in Mali,” Mr Welborn said.
“The Mt Wright ore body has been a wonderful and very successful operation for Resolute; we mine 2.5 grams per tonne (g/t) ore body to 900m underground at a cash cost across that timeline of $850 an ounce, so that is a phenomenal achievement of our operating team.
“Unfortunately, geologically, the ore body pinches out at the depth we’re now out; we’ve depleted it and in fact, as of today we’ve actually mined more gold than we ever defined in our reserved resources model, so in fact we’re effectively over-drawing on our reserves at Mt Wright.”
Mill 1 scats screen at Nolan’s processing plant.
Finding a Future
Resolute readily acquired Ravenswood from Xstrata in 2006, which at that point was a 5 million tonnes per annum (mtpa) open pit operation based on the Sarsfield pit.
Mr Welborn said Sarsfield was a relatively large, but modest grade ore body.
Resolute found greater success at Ravenswood by building its underground mine 10km away from the Sarsfield pit at Mt Wright.
The gold miner ran its mill at 1.3mtpa, exclusively mining the Mt Wright deposit.
Its expansion plan would see a staged return to 5mtpa open cut mining, with the original plan to mine Nolans East, followed by Sarsfield and the relatively new discovery at Buck Reef West.
However, a successful approvals process with the QLD Government has allowed Resolute to prioritise operations at Buck Reef West, which is a higher-grade and less complicated ore body than Sarsfield.
Resolute now plans to open up and start mining the Buck Reef West deposit from July 2019, with plans to mine Sarsfield from 2025.
Mr Wellborn said mining would continue at Mt Wright until the end of FY19, with mining already finished at Nolans East.
“What we’ve been able to do by maintaining our production at Mt Wright is find a future by going back to open pit mining at Sarsfield, Nolans, and the relatively new discovery immediately adjacent to Sarsfield, which is Buck Reef West,” Mr Welborn said.
“We’ve managed to define a 14-year mine life for the asset based on the 4 million ounces of resources we’ve defined within a 4sqkm radius of our 5mtpa capacity mill, so that’s quite exciting.”
Mr Welborn said all-in sustaining costs at Ravenswood were now just below $1100 an ounce.
“It’s a significant margin with current gold prices and we believe there is again potential to increase that production to up to about 140,000 ounces a year,” Mr Wellborn said.
Automatic Success
Mr Welborn said the success of the expansion had not just been about innovative thinking, but also the support of the QLD Government and Resolute’s embrace of new technologies.
“When talking about Ravenswood, Buck Reef West and Sarsfield, the ability to keep this mine going has been driven by a successful partnership with the QLD Government in achieving all of the mining, environmental and heritage approvals we require,” Mr Welborn said.
“The second important thing not to miss is that the resources at Sarsfield and Buck Reef West have been known about for some time.
“The reason why the Ravenswood expansion project wasn’t defined earlier is that we’ve augmented the economics of the project through the use of technology, including beneficiation of the ore body, which allows us to process less tonnage and increase the mine head grade of what is a modest grade ore body, significantly improving the economics.
“The ability to get the environmental approvals we need has also been taking the QLD Government on a journey around new technologies and new ways of dealing with that material, so I think that’s the other aspect of the story.”
Mr Welborn believed Resolute’s embrace of new technologies would be repeated across the Australian mining sector as an effective way of increasing production and maximising profit without being overly reliant on market forces.
Among the technologies championed by Resolute has been automation, with Syama set to be the first purpose-build automated underground mine, which would allow Resolute to increase production and safety, while lowering costs.
“You can have more much control with automation because you can track and digitally manage every kilogram of ore with some degree of certainty, so we believe we’ll get better machine life and much better maintenance scheduling,” Mr Welborn said.
“One other aspect is that with the use of really high technology, innovative and adaptive automation allows us to train our local African workforce in a way that we haven’t been able to do before.
“I use the analogy of my 80-year-old mother who could never work out how to use a VHS video recorder for me in the 1980s when I was at university and wanted her to record a show for me, but she’s happy to surf the internet on her iPhone and send me text messages.
“That’s because that technology has no instruction book; like automated technology, it’s intuitive and easy to use.”
Mr Wellborn said many of the benefits of automation could and already had been translated into the Australian mining sector.
This included tele-remote technologies Resolute pioneered at Mt Wright, including tele-remote bogging.
“I am convinced that mining, particularly underground mining is going both electric and automated as technology improves,” Mr Wellborn said.
“The training and control advantages are particularly relevant for remote operations whether they be in Australia or in Africa.”
Mr Welborn said if done well, automation could have no negative impact on workforces, while maximising benefits to shareholders.
“When we’re talking about automation technology, there’s a theme around what Resolute has been able to do with its asset base over the last couple of years, which is very much the creation of shareholder value through the adaption of new technologies,” Mr Welborn said.
“At Syama, we have taken what was a $US880 all-in sustaining cost mine down to less than $US750, largely through three main areas of applying technology; automation in our underground mining, refinements and improvements to our processing infrastructure to get higher recoveries and efficiencies, and more environmentally powerful solutions in our power generation.”
Resolute has staged a return to open cut mining from underground mining at Ravenswood.
Outlook
According to Mr Welborn, Resolute’s outlook for the future would be centred on growth.
“We’re a 300,000 ounce a year producer on our way to 500,000, and we’ve been focussed over the last couple of years on the transformation of Ravenswood and Syama,” Mr Welborn said.
“I’ve said success there would allow us as a company to spread our wings and do even more exciting things; I think that’s the next phase of our growth.
“I think there are wonderful opportunities for us in Africa – we’ve been operating in that region for more than 20 years, and geologically, politically and economically I’m convinced it’s an area of huge opportunity for Resolute.
“Our portfolio investments in juniors, largely with exposure to emerging and growing resource positions on the African continent, is very much focussed on where our next mines are coming from.”
Mr Welborn said Resolute remained focussed on 10-year mine lives capable of producing more than 100,000 ounces in a year, and representing real value for shareholders.
Resolute has owned and operated Syama, originally owned by BHP, for about 10 years and expects it to have a 14-year mine life.
The company also operates the Bibiani gold mine in Ghana.
Bibiani, formerly operated by Anglo Gold Ashanti, is currently in care and maintenance, though Resolute’s plans to develop it were progressing well.
It has a 10-year mine life and an all-in sustaining cost of just over $US750 an ounce.
Together, the three mines would push Resolute’s production to 500,000 ounces by 2021.
