Mining companies dig deep in quest to be sustainable, curb use of energy
Part of cohort with green ambitions, Goldcorp plans to open all-electric mine
About a 10-hour drive northwest of Toronto, in an area with no history of mining and little exploration, Goldcorp Inc. is tunnelling a hole, currently at least 120 metres below the pine tree forests and lakes that dot the surface, for what it hopes will be one of its most sustainable mines yet.
Borden, as the mine is to be called when it starts producing in 2019, will be modest in size at about 250,000 ounces of gold per year under current estimates.
But Goldcorp harbours big ambitions to make it the first all-electric underground mine in Canada where everything from the trucks that haul ore, to the ventilation system that provides oxygen to its subterranean workers, run off energy taken from the electrical grid.
All mines are finite projects, making them in one sense, unsustainable. Still, in an era when countries around the world have pledged to curb carbon emissions, many mining companies are citing “sustainability ” as a core value and are making strides to limit their environmental impact.
Barrick Gold, Endeavour Silver Corp. and other companies released reports in the past month that sought to measure their “sustainability” by looking at environmental impacts, community relations, safety records and other metrics.
With diesel prices rising in tandem with oil prices, the quest for sustainability also has pushed many companies to look closely at their energy usage.
“It’s not just necessarily because of the environment,” said Brent Bergeron, Goldcorp’s executive vice-president of corporate affairs and sustainability. “There’s very interesting financial benefits we can get by actually becoming smarter about how we produce and use power generation at our sites.”
In choosing a mine to experiment with how to wean itself off diesel, the Borden project made sense, he said, because of its small size and its location in Ontario, where a cap-and-trade program came into effect earlier this year. The program sets a limit on a company’s greenhouse gas emissions, above which they need to purchase credits at auctions.
Although electricity is expensive in Ontario, Bergeron said there is access to renewable energy sources such as hydro, which will lower the company’s carbon footprint.
Inside the mine itself, it is also using electric-powered 40-tonne haul trucks, he said.
“Those trucks don’t exist yet,” Bergeron said, adding that the company urged the supplier to build them or else the company would find a different supplier that could build them.
There are also obvious benefits to switching to the grid. By using electricity for its air ventilation system, Goldcorp stopped spewing diesel particulate into the air it must keep clean for its workers, he said.
“I think that what you’re seeing today is mining companies trying to really push the sustainability side of what we’re doing,” said Bergeron, “but also look at it from the point of view of these technologies do exist, they have been proven, so let’s try and get them into some of our projects.”
Other companies cited additional benefits of moving their mines off diesel and onto the grid completely unrelated to the environment.
Pan American Silver Corp., which recently released a report on its sustainability, built a 98-kilometre power line to connect its open pit silver gold Dolores mine in Mexico to the national power grid.
Constructed in late 2016 at a cost of $20 million, it has resulted in savings of about $9 million per year, according to spokeswoman Siren Fisekci.
Located in an area of Mexico that has been riven by violence, possibly linked to drug cartels, last month, the mine temporarily closed after a decapitated body was found on a road near the mine.
“When we bring supplies in there, you’re looking at 120 to 140 kilometre road to bring them in there,” said Fisekci, who added that the power line allows the mine to operate regardless of conditions on the road.
Some mining companies say energy accounts for 10 per cent of operating costs at a mine, which is inducement enough to look for savings through renewable energy or otherwise.
Meanwhile, on another continent, amid the dusty, semi-arid landscape of northern Namibia in southern Africa, executives from Vancouver-based B2Gold Corp. stood with local dignitaries in early June to ring in the opening of a seven megawatt solar panel plant it built to help power its nearby open pit gold mine.
Built at a cost of $8.5 million, it is expected to help the company save about 13 per cent on its energy usage at the open pit per year — about $16.5 million over the next decade or so, according to the company.
Bill Lytle, senior vice-president of operations for B2Gold, acknowledged that the open pit mine would “scar the earth,” but also noted that the mine had an estimated lifespan of about 10 years, depending on whether there is future exploration and other factors. Regardless, at the end of the mine life, the plan is to fill the pit with water and make it into a lake, then convert the surrounding area into a nature reserve, he said.
Meanwhile, the solar plant has a lifespan of 25 years, meaning it could outlast the mine.
“I think all mining companies will tell you to some degree they ’re doing some sort of sustainability,” said Lytle. “It is a requirement to maintain your social licence to operate.”