A quest to coexist

ONTARIO, CANADA. Goldcorp is developing the world’s first all-electric underground mine, an ambitious project the company hopes will help inspire an industry-wide shift to more sustainable mining.

This isn’t the most instinctive location to build a mine.

Goldcorp’s Borden Lake project lies just south of the Chapleau Crown Game Preserve, the world’s largest at 2 million acres (700,000 hectares). The portal is a stone’s throw from the pristine body of freshwater for which the mine is named, brimming with trophy fish each spring. Part of the orebody Goldcorp will ultimately mine sits beneath the lake, whose water is sacred for the area’s four First Nations communities.

It’s no surprise, then, that Borden project manager Luc Joncas uses words like “invisible” and “silent” when he describes the development aims of the region’s first mine.

“Mining is brand new in this area, so it’s essential to build a sustainable mine,” Joncas says. “We want to be accepted by the neighbours, whether it’s the First Nations that live next to us or even the cottagers around the mine.

<p>Maarten van Koppen, senior project engineer at Goldcorp.</p>

Maarten van Koppen, senior project engineer at Goldcorp.

Goldcorp senior project engineer Maarten van Koppen produced Borden’s pre-feasibility study and all associated engineering leading up to it.

“We knew that we had to create a mine in close collaboration and coexistence with our local stakeholders,” he says. “It was very important to us to minimize all sources of emission, whether it’s noise, dust or other pollutants. Going electric really helped in achieving those goals.”

Goldcorp has designed Borden Lake to become the world’s first all-electric underground mine when it reaches commercial production next year, an undertaking the company expects to not only help minimize community and environmental impact but also improve health and safety for employees – all while boosting Goldcorp’s bottom line.

John Mullally, Goldcorp’s director of government affairs and energy, considers a shift to cleaner, more sustainable mining practices essential.

“There’s so many societal expectations and changing views on things like climate change,” Mullally says. “For us to be a modern company, we have to be moving sort of at the same rate as changes in society, so I think that energy overall, and climate change specifically and mitigating our impacts to climate, that’s become a big focus in the last three to five years with Goldcorp. We’re changing the culture inside the company and we want to encourage a change in culture across the industry.”

By the time Borden is in full production, there will be no diesel-powered equipment underground. A combination of tethered electric and quick-charge battery-powered equipment will comprise the entire fleet.

“The battery technology advancements really enable us to go fully electric,” Joncas says. “Not only do we plan to prove to the industry it’s possible, we’re keen to prove that it will be cost effective and bring even more value to our shareholders than a conventional mine. We believe electrifying Borden makes sense economically, environmentally and socially.”

By eliminating diesel underground and fully electrifying Borden, Goldcorp anticipates a 70 percent reduction in greenhouse gases and annual savings of 2 million litres of diesel fuel and 1 million litres of propane. The company also expects to save 35,000 megawatt hours of electricity yearly, due in large part to drastically reduced ventilation needs.

<p>John Mullally, Goldcorp’s director of government affairs and energy.</p>

John Mullally, Goldcorp’s director of government affairs and energy.

“Electrification is the ultimate win-win, especially complemented by innovations like ventilation on demand and full connectivity,” van Koppen says. “The main benefits that we see with going electric are certainly the elimination of fuel, reduced maintenance, reduced greenhouse gases, reduced power consumption, and of course the biggest one is the elimination of diesel particulate matter in underground environments, which is hugely beneficial to the health of the workforce.

<p>Jumbo operator Randy Harrison.</p>

Jumbo operator Randy Harrison.

“We were able to eliminate a return air raise and our intake raise, we could reduce the diameter from five metres to four metres, so there’s big cost savings to be had if you set it up right from the get-go.”

Miner Randy Harrison appreciates the absence of underground emissions at Borden after working in conventional diesel mines across four continents since 1980.

“This is like no other underground environment I’ve ever worked in,” Harrison says. “The air is so fresh.”

He’s behind the controls of a Sandvik DD422iE, one of two identical units Goldcorp depends on to develop Borden’s access ramp.

“The computer setup and the preciseness that you can get on the face, bar none, best jumbo they got around,” says Harrison, who’s operated development drills since 1989. “Sandvik has been on the cutting edge right from day one since I started operating them.”

Joncas calls the jumbo “the star of the fleet.

“It enables better accuracy, more control, consistency from crew to crew. For us it enables also a safer operating workplace. We start from a fresh face with virtually no bootlegs. We manage the profile better and have less overbreak. It allows us to optimize the drilling pattern. Our holes are higher quality.”

Sandvik DD422iE is connected to the grid at Borden while drilling, during which the jumbo charges the battery it uses to manoeuvre between faces.

Goldcorp

Goldcorp is a leading gold producer focused on responsible mining practices with low-cost production from a high-quality portfolio of mines throughout the Americas. A Canadian company headquartered in Vancouver, British Columbia, Goldcorp employs more than 15,000 people worldwide and is committed to being responsible stewards of the environment and to maintaining the highest health and safety standards.

“We thought charging-while-drilling was a great concept, something that could potentially be very valuable in other equipment in the future,” Joncas says. “I was impressed that the jumbo can handle multiple voltage standards. We had a training camp at a mine with a 600-volt standard, and the jumbo works equally well on the 1,000-volt network here.”

The rig’s fully integrated battery technology means no change-outs, a safety and productivity benefit, Joncas says. He also cites the regenerative braking system as a plus and says the electric driveline in Sandvik DD422iE makes it much easier to maintain than conventional jumbos.

“When we purchased the fleet, one thing we were extremely attracted by was the fact that a lot of the mechanical components are removed,” Joncas says. “No more diesel engines, no more oil changes to be done.”

Goldcorp bought Borden from a junior explorer for 526 million US dollars in 2015. With current gold reserves of 950,000 ounces, the operation figures to produce more than 100,000 ounces per year over at least a seven-year mine life.

“We are confident that our exploration will extend that,” Joncas says. “The longer our mine life, the more cost-effective our initial capital investment in an all-electric fleet.”

Ore will be trucked 160 kilometres (100 miles) to Timmins for processing at the Dome mill at Goldcorp’s Porcupine Gold Mines.

“Using an existing facility that operates extremely efficiently and not having to permit and build a new mill and tailing facility minimizes our cost and our environmental footprint,” Joncas says.

Decline construction at Borden began in mid-2017 and a 30,000-ton bulk sample is expected to be extracted and analyzed by the end of this year with production expected to begin in 2019.

Borden Lake project

The Borden Lake gold project is being developed as the world’s first all-electric underground mine. Decline construction began in mid-2017 and a 30,000-tonne bulk sample is expected to be extracted and analyzed by the end of this year, with production expected in 2019. Located in Ontario, approximately 11 kilometres northeast of the town of Chapleau and 160 kilometres southwest of Timmins, Borden Lake has gold reserves of 950,000 ounces and is part of Goldcorp’s plan to increase production by 20 percent by 2021. By eliminating diesel underground and fully electrifying Borden, Goldcorp anticipates a 70 percent reduction in greenhouse gases and annual savings of 2 million litres of diesel fuel, 1 million litres of propane and 35,000 megawatt hours of electricity.

“We believe Borden will be a great pilot to prove that there are tremendous financial and environmental benefits from the adoption of cleaner technology,” Mullally says. “It’s really exciting to be a part of. Once other companies see that the business case works, we hope to see large scale adoption at a meaningful rate across the mining industry.”

Sandvik DD422iE

Sandvik DD422iE is an electric development jumbo designed to drive down production costs while reducing the environmental impacts of drilling and tunnelling. By using electric energy from an onboard battery during tramming, Sandvik DD422iE produces zero emissions while manoeuvring between headings. This improves health and safety for miners working underground. Less diesel usage in a mine thanks to diesel-free drilling can ease ventilation requirements, while also reducing associated diesel logistics and maintenance expenses. Using a mine’s existing electric infrastructure, the Sandvik driveline technology enables the battery to recharge during the drilling cycle. The battery will even recharge while Sandvik DD422iE is tramming downhill, using energy generated by the braking system.