Innovation in mining could lead to less environmental impact
It sounds simplistic, but innovations in mining — from the development of sensor-driven autonomous mining machines to advances in the microbiology of minerals — promise viable alternatives for miners to operate on a smaller scale.
“If you look at (mining) on a global basis, the ability for us to fund or develop these big-scale mines I think is very questionable already,” said Kip Jeffrey, head of the Camborne School of Mines at the University of Exeter in the U.K.
Jeffrey was in Vancouver earlier this fall to help spark that conversation with a presentation for an audience of about 160 mining executives, consultants and academics in the sector and the topic is gaining resonance here.
“It’s a question of time, but there’s no doubt in my mind we will find ways to mine differently in British Columbia,” said Scott Dunbar, head of the Norman B. Keevil Institute of Mining Engineering at the University of B.C.
B.C. is endowed with “incredible mineral wealth that could be exploited,” Dunbar said. But miners face challenges in finding new, often low-grade deposits, absorbing the enormous costs to build large mines and then public push back over the impact of such big projects.
“Then there’s the staggering amounts of waste you produce,” Dunbar said. “Any one of those things could stop you dead in your tracks.”
B.C. has 15 operating mines, including large projects such as Centerra Gold’s $1.3-billion Mount Milligan mine northwest of Prince George and Imperial Metals Corp.’s $643-million Red Chris mine in B.C.’s remote northwest.
Among projects under development, however, is Seabridge Gold Inc.’s Kerr, Sulphurets and Mitchell (KSM) gold and copper mine in the remote northwest, which is working its way through permitting that comes with a forbidding $5.3 billion estimated price tag.
In 2015, Seabridge CEO Rudy Fronk told Postmedia News that the project requires a major partner to step in and the list of global companies with deep enough pockets to take it on was short. The development also faces considerable opposition from conservation groups in Alaska downstream from the KSM site.
Other B.C. projects have fallen to environmental concerns, such as Taseko Mines Ltd.’s promisingly rich New Prosperity proposal for a $1 billion open pit gold and copper mine southwest of Williams Lake, which was twice rejected in a federal environmental review.
Globally, Jeffrey said a substantial majority of mining projects that are being built are going over budget.
“The choice then becomes do you never develop the deposit, or do you say, ‘well, we will look at this more rightsized mine for that particular location,” Jeffrey said.
Tools for building that “rightsized” mine, Jeffrey said, could include autonomous mining machines that with advanced sensors that can independently burrow underground and dig out minerals, Jeffrey said.
These can be built smaller than traditional mining equipment, Jeffrey added, because they don’t have to accommodate human operators, Jeffrey said, and would be capable of zeroing in on narrow veins of minerals rather than carving out huge areas of additional waste rock in between them.
Not digging up so much waste, putting a smaller amount of ore through a processing plant and building a smaller processing plant in the first place, all shrink the size of a mine.
“(And) those perhaps biggest-impact things that you see at a mine, I wouldn’t say disappear entirely, but they’re dramatically reduced,” Jeffrey said.
Using biochemistry, injecting microbe-containing fluids capable of dissolving minerals underground that can be pumped back to surface — referred to as in situ extraction — is another innovation showing promise as a means for miners to avoid having to dig up massive amounts of rock.
Instead of excavating a pit, miners would drill into rock and pump fluids underground with microbes capable of dissolving minerals, which are pumped back to surface to recover the ore.
Dunbar, at UBC, is collaborating with biochemists to develop a biological method to draw dissolved metals out of mine waste water.
The first advantage of the technique is to reduce the environmental impact of discharging mine waste water into the environment. However, it also recovers some of the valuable minerals left behind.
Dunbar said that while researchers need to learn more about how the “mineral microbiome works,” the hope is that they’ll be able to use the techniques in mining itself.
Smaller-scale innovations also give miners an opportunity to look at old mines in new, less capital-intensive ways, Jeffrey said.
Vancouver-based Strongbow Exploration Inc., is contemplating some of those innovations in its project to revive a tin mine at the southwest tip of Cornwall in the U.K.
Called South Crofty, the underground mine was last shuttered in 1998 and Strongbow CEO Richard Williams said finding ways to minimize activity at the surfaces is paramount in their planning since the mine site is in the middle of Camborne, a town of 25,000 people.
Williams said existing underground shafts in an area that has been mined for hundreds of years gives Strongbow an advantage because they can be used to store waste rock instead of building a tailings facility at surface.
He said the company is also exploring the use of new technologies for sorting rock to separate tin-containing rock from waste rock underground, which will reduce the amount of ore that they need to haul to the surface.
That saves energy, both in moving ore to the surface and processing it, Williams said.
“Anything that reduces environmental impact, anything that reduces power consumption, anything that improves working conditions, you have to look at,” Williams said.
“It’s your responsibility as a company, not just to your employees, but the whole community.”
Adopting such techniques, however, has challenges, Jeffrey said, when mines being built now cost billions of dollars. Miners can’t afford to take big risks while paying back that amount of capital.
“That’s where conservatism, if it exists, is,” Jeffrey said.
For the moment, the mining industry is working to automate segments of traditional mining, with driverless haul trucks and autonomous equipment used in open-pit mining such as the rock drills and excavators.
However, Vancouver companies such as Integra Gold Corp. and Goldcorp Inc. are among those looking to push the boundaries of innovation.
The companies, last week, launched a contest under the title Disrupt Mining in which it is inviting applications to showcase ideas with “the potential to revolutionize the future of mining.” The prize is up to a $1 million investment from the partners and a chance to do a proof-of-concept test at one of their mines.
“The mining industry is overdue for radical, disruptive innovation,” said Goldcorp senior vice-president Todd White.
In the longer term, Jeffrey estimated sensor-driven robotic machines could be used to selectively mine within the next decade.
“Two years ago I might have said this was in the realm of science fiction and somewhat fanciful,” Jeffrey said. “I can’t say that now because some of those things are actually happening.”