Giant Mine - Yellowknife-3993

This is Giant Mine

This gold mine was once so dangerous that it killed a toddler who ate snow two kilometres away. Canada’s second-largest environmental liability is inside Yellowknife city limits — and intrinsically tied to the city’s history and future. The federal government has now inherited the billion-dollar cleanup effort that could span a century

Space-age pipes loom over me, two-pronged fingers jutting straight up at the sky.

They plunge into the earth under our feet, where, like a steampunk Lovecraftian nightmare, the pipes full of carbon dioxide freeze a quarter-million tonnes of deadly arsenic trioxide dust to keep it dormant in perpetuity.

The size of an office building, the test chamber below is the first, and the smallest, of 15; there’s a long way to go before all of the dust is contained.

This is the future of what was for 60 years the crown jewel of Yellowknife, the economic driver of the North, until it finally closed in 2004.

This is just one part of a billion-dollar cleanup that will take another generation, and, even then, require supervision and maintenance forever lest it break down and poison us again.

This is a 900-hectare maze of dusty tailings ponds, yawning open pits, poisoned water, toxic soil and decaying buildings full of arsenic.

This is Giant Mine.

Photos by Matt Jacques.

A lump in the bay

Yellowknife’s history, and its destiny, has always been tied to one mineral or another, even drawing its name from the copper tools preferred by the Yellowknives Dene who inhabit the region. It’s situated where the slow-moving Yellowknife River drains into Great Slave Lake, almost exactly 1,000 km north of Edmonton.

In the early 1930s, what is now Yellowknife was a backwater compared to the nearby Hudson’s Bay Company trading post at Fort Rae. But a young Dene woman named Mary Fishbone would have encountered plenty of white Canadians as they passed through, prospecting or preaching. When she found a lump of shiny rock in the bay, while she was out foraging on her First Nation’s territory, she gave it to her priest — or, as some versions of the story have it, traded it to an unscrupulous prospector for a stovepipe. Mary Fishbone’s name is forgotten in the history of the mines, except by her descendants, who keep photos of her on their walls and readily tell her story to visitors.

The story is possibly apocryphal; searches in the NWT Archives and the Geological Survey of Canada came up empty, (“there’s a story like this for every find,” an archivist tells me over the phone) though that alone doesn’t mean it’s untrue, and there had been some gold discovered by a prospector near the turn of the century. But regardless of who initially discovered the gold, the ensuing years would be devastating to the Yellowknives Dene.

By 1934, prospectors had arrived and found more gold in the region, opened the Burwash mine across Yellowknife Bay, and things began moving quickly. On the south end of Yellowknife, overlooking Great Slave Lake, Con Mine poured its first gold brick in 1938. The same deposit would soon give rise to three other new mines: north of the city, the Ptarmigan and Tom mines. Right next to Con, the Negus mine operated for 13 years before its neighbour acquired it.

The population swelled, and when men returned from the war in 1944, the extent of the potential development at Giant Mine ramped the excitement up further. Digging through the bedrock for gold, the mines themselves became the bedrock of the city.

But there was one huge catch to all the feverish development, which wouldn’t become obvious until at least one child had died and many more been sickened by the air and water around them.

Giant consequences

The gold found at Giant Mine is microscopic, contained in rocks that need to be physically crushed then heated to extremely high temperatures to free the tiny specks of gold. But there isn’t just gold in the rock — there’s another notable mineral lurking inside, and that’s where the billion-dollar problem began.

Arsenopyrite is a mineral often found alongside gold, silver, lead and other valuable minerals. It’s common across the Yellowknife landscape, folded into the bedrock. In crystalline form, it’s a beautiful silver or white mineral. Worn down, it looks like any other rock. And when it’s crushed, melted and blasted into the sky, the arsenic trioxide dust, as fine as baby powder, is deadly.

The Materials Safety Data Sheet for arsenic trioxide classifies it as a confirmed carcinogen that may cause damage to blood, kidneys, liver, the cardiovascular system and the central nervous system, and cautions, “Keep locked up. Do not ingest. Do not breathe dust. Wear suitable protective clothing. If ingested, seek medical advice immediately.” Until 1958, Giant Mine was pumping as much as 7,400 kg of arsenic trioxide dust into the air every day, and as the mine produced more and more gold, the byproduct floated through the sky and precipitated onto the earth, coating the landscape and poisoning the water.

Yellowknife Bay used to be a prime fishing spot, and its surrounding lands used for hunting, trapping and foraging for berries and medicines like Labrador tea or spruce gum. Baker Creek was reserved for hunting moose and picking the blueberries that carpeted the land. Today, after 70 years of heavy industrial use, the creek is only just starting to recover, with grayling spawning in its water.

In 1951, a toddler died from eating snow.

The toddler was a relative of Elder Muriel Betsina, who today lives in Ndilo, a Yellowknives Dene community across Back Bay from Giant Mine. Though she only arrived in Yellowknife in 1962 after she left residential school, she immediately saw the effect the arsenic was having on the community.

“We got so scared,” Betsina recalls. Children were getting rashes from wearing clothes washed in the same lake water that had always been a clean source for the community.

“‘One day all this arsenic will kill you’ — nobody ever explained that to us,” she says.

On the way out of Ndilo from Betsina’s house, I pass K’alemi Dene School, where VICE News’ Hilary Beaumont reported in December that the soil has been tested at nearly three times the safe exposure limit for arsenic. Children play on a fenced Astroturf field.

Meanwhile, researchers from the University of Ottawa have begun taking fingernail clippings and urine samples from locals to measure how much arsenic remains in the people who live here.

The government has never compensated the Yellowknives Dene for the loss of their land, or the health impacts of the arsenic on their health. A letter the territory sent to the federal government to demand compensation and an apology for the First Nation was met with a simple acknowledgment, but no promises.

By 1960, the mine had drastically cut back its arsenic emissions with the installation of new technologies. But it didn’t stop the gold-smelting process from producing the poison, only from emitting it out the stack. That’s where the 237,000 tonnes of arsenic came from; it was caught, gathered up and air-pumped back underground for safekeeping. That left Indigenous and Northern Affairs Canada with a seemingly impossible task: to secure, for at least 100 years, chamber upon chamber of fine deadly dust.

The committee reviewing 56 possible options to store the arsenic trioxide considered freezing the best among them. That’s why, today, the pronged carbon dioxide-filled tubes act to essentially siphon heat out of the dust, day and night, with no power input required. It’s not a final solution, but it’s stable.

“We don’t know what the solution could be,” says Natalie Plato, deputy director of the Giant Mine Remediation Project. “We’ve noticed there’s a fungus growing on one of our chambers, so there’s a fungus that’s thriving in the highly arsenic-ridden environment. So perhaps there’s a superbug that could eat this in place. We don’t know; it’s strictly science-fiction.”

She, like most professionals involved in the Giant Mine cleanup can’t help but roll her eyes a little at the oft-repeated suggestion that this much arsenic trioxide could kill every human on the planet.

“A tanker truck, actually, could kill every person on the planet if you put it in water and everyone drank it,” she says — what’s buried at Giant is much, much more than a tanker truck. It’s just a matter of keeping it in.

Scrubbing water

Plato stops her vehicle at an overlook on our tour of the Giant Mine site. She tells me she arrived here seeking a greater technical challenge, having begun her government career remediating relatively “boring” Cold War-era Distant Early Warning sites across the High Arctic.

Standing between the remains of the roaster — sequestered in 360 shipping containers in neat rows awaiting burial in the mine — and the cracked bed of a contaminated tailings pond, it’s clear that challenge is something in abundant supply at Giant Mine. The cleanup effort encompasses water treatment, deconstruction of 100 contaminated buildings, extensive underground operations and, of course, freezing an unimaginable quantity of arsenic trioxide — all within a few kilometres of a major city.

Workers will cover the tailings ponds with sheeting and then with gravel, instead of replanting them with grasses and trees. This is at the request of the Yellowknives Dene, Plato says; the First Nation didn’t want the remnants of the toxic ponds to look inviting to future wildlife or foragers.

While that work is happening, the current challenge is water. Between 100 and 400 million litres of water are pumped up from 230 metres below ground each year, and it all needs to be treated to remove the arsenic before it can be discharged into Baker Creek, which empties into Great Slave Lake. For now, the water just needs to meet industrial levels of arsenic, but soon, the water will need to be cleaned to a much higher standard. That will require an entirely new treatment plant, all for a mine that went out of operation nearly 15 years ago.

“We need to up our game,” she explains, if the water is to be treated to the point of being drinkable.

The water licence today is the same as it was when the mine was operational. It doesn’t allow for a landfill on the site (and, as Plato explains, at least some of the garbage generated on site would have been dumped in the tailings ponds) so for now, equipment, decaying buildings, cables  mine carts and other detritus litters the ground.

Underground, it’s even worse; chambers that the various owners should have backfilled as the mining moved around remain empty, a stability hazard for the mass of toxic dust waiting to be kicked up by a collapse. Now the workers are mixing old tailings with cement to reinforce the gaping holes underground.

The federal government recently awarded U.S. contractor Parsons Inc. a $32 million contract to monitor the site for the next two years while it works out the final cost to actually finish the cleanup. It’s expected to be up to $900 million; $356 million has already been spent just warding off catastrophe.

Lessons not learned

There’s a model the size of a large coffee table inside an innocuous storefront on Yellowknife’s main drag.

The storefront is the office of the Giant Mine Oversight Board, an independent body set up in 2015 to act as a watchdog, observing the process of remediating the mine from start to finish. The model depicts the underground extent of both the Giant and Con mines, which bookend the city to the north and south, respectively. The two mines combined look like they make up easily more road underground than there is in the city itself — in the case of Con Mine, stretching under Yellowknife’s roads, schools and homes.

The aboveground impacts of the Giant, Negus and Con mines extend further than the eye can see as well. Prevailing easterly winds blew the arsenic dust across the landscape to the west of the site, creating a cone of contamination that only fades 25 kilometres away from the former roaster. That left the landscape around Yellowknife, a Swiss cheese pattern of lakes and ponds, burdened with high levels of arsenic. Even on Frame Lake — which, in the middle of the city, borders the legislature, City Hall, welcome centre, two parks, museum and swimming pool — signs prohibit fishing, swimming and drinking the water, and the same goes for most of the lakes in and around the city.

There is currently no plan to clean all of them up. Neither the city, federal, nor provincial government has yet taken responsibility for contamination outside of the actual mine site, and the oversight board has criticized the remediation project in its first two reports for failing to figure that out.

Giant Mine may not be the last of its kind. The mine became the taxpayers’ problem when its final owner, Royal Oak Mines, went bankrupt. That has happened again and again, with remediation costs for mines like the Jericho, Colomac and Terra mines all falling on taxpayers.

“It’s a troubling pattern and it hasn’t been fixed,” MLA Kevin O’Reilly told The Narwhal. “In fact, we continue to see mines that go down without adequate financial security [to pay for cleanup].”

The result of decades of loose requirements for upfront security is the Northern Contaminated Sites Program, a federally funded program that as of 2014 is responsible for $2.369 billion worth of cleanup projects — mostly mines that have gone bust as their owners walked away. The Giant and Faro mines occupy the bulk of that funding.

Today in the Northwest Territories, mining and oil and gas remain by far the single largest industry, though diamonds have taken over for gold. The oil and gas industry is sputtering out; in Norman Wells, the only major oil play in the territory, Imperial Oil is winding down. The day I visit Giant Mine, Imperial representatives are also visiting, to get tips on how they can clean up their own sites as they pack up for good.

Now there are rumblings of a new mine: the TerraX City Gold project, which has already staked the last remaining claims surrounding the city, even including islands in Great Slave Lake. It would dive deep into the area’s “greenstone belt” in search of the same plentiful gold that made Giant so giant.

At the same time, the government is developing new legislation to govern mining. That legislation, in its current form, would have the same department that advocates for mining also be responsible for regulating it.

“That’s a conflict of interest,” says O’Reilly. “You can’t have the promoter being the regulator.”

One day about three years ago, Muriel Betsina looked out across Back Bay and saw a black cloud of dust moving across the water. Dust sensors located around the site today give reassuringly low readings of dangerous chemicals, but, terrified by her years of living in the shadow of the mine, she later went out and scrubbed down her entire house and driveway.

The arsenic dust hasn’t just coated the landscape; it still swirls around in the minds of the people who remember babies with full body rashes, fish with lesions on their livers and Labrador tea pots ringed with mysterious chemicals.

Sitting in her home, in full view of the long overdue cleanup, she doesn’t mince words.

“We’ll never recover.”

Another year of keeping a close watch
Here at The Narwhal, we don’t use profit, awards or pageviews to measure success. The thing that matters most is real-world impact — evidence that our reporting influenced citizens to hold power to account and pushed policymakers to do better.

And in 2024, our stories were raised in parliaments across the country and cited by citizens in their petitions and letters to politicians.

In Alberta, our reporting revealed Premier Danielle Smith made false statements about the controversial  renewables pause. In Manitoba, we proved that officials failed to formally inspect a leaky pipeline for years. And our investigations on a leaked recording of TC Energy executives were called “the most important Canadian political story of the year.”

As the year draws to a close, we’d like to thank you for paying attention. And if you’re able to donate anything at all to help us keep doing this work in 2025 — which will bring a whole lot we can’t predict — thank you so very much.

Will you help us hold the powerful accountable in the year to come by giving what you can today?
Another year of keeping a close watch
Here at The Narwhal, we don’t use profit, awards or pageviews to measure success. The thing that matters most is real-world impact — evidence that our reporting influenced citizens to hold power to account and pushed policymakers to do better.

And in 2024, our stories were raised in parliaments across the country and cited by citizens in their petitions and letters to politicians.

In Alberta, our reporting revealed Premier Danielle Smith made false statements about the controversial  renewables pause. In Manitoba, we proved that officials failed to formally inspect a leaky pipeline for years. And our investigations on a leaked recording of TC Energy executives were called “the most important Canadian political story of the year.”

As the year draws to a close, we’d like to thank you for paying attention. And if you’re able to donate anything at all to help us keep doing this work in 2025 — which will bring a whole lot we can’t predict — thank you so very much.

Will you help us hold the powerful accountable in the year to come by giving what you can today?

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That’s right — all donations are being doubled until Dec. 31. The Narwhal’s independent journalism is made possible by readers just like you who give what they can. Will you help us break big investigations in 2025?
An illustration of two narwhals, facing each other. the one on the left has tied on a second tusk, with a caption reading: "What? I thought doubling up was *in* right now." Illustration by Gabrielle Drolet