Tailings Pond at Copper Mountain Mining Corporation Similkameen Princeton BC Canada

B.C.’s Copper Mountain mine proposes major tailings pond expansion, sparking cross-border concern

The expansion could increase the height of a dam holding back mining waste to 255 metres — taller than Vancouver's highest skyscraper — without requiring an environmental assessment

A B.C. mine that was fined $51,000 for unauthorized release of wastewater late last year is proposing to increase its tailings pond capacity by 70 per cent in a move that won’t automatically trigger an environmental assessment.

At 155 metres high, the Copper Mountain mine’s tailings pond dam is already four times taller than the Mount Polley mine tailings dam, which caused the largest mining spill in Canadian history when it failed in 2014. Now, a proposal by the Copper Mountain Mining Corporation to increase the allowable height of the dam to 255 metres — potentially making it taller than Vancouver’s highest skyscraper — is sparking concern.

The Copper Mountain mine, located about 20 kilometres south of Princeton, straddles the Similkameen River, which flows south through the province before draining across the Canada-U.S. border into Washington State’s Okanogan River. 

Downstream residents in B.C. and Washington are frustrated the proposed mine expansion appears to be moving forward without an environmental assessment. 

The expansion would also more than double the mine’s permitted discharge into the Similkameen River, from 60 litres per second of treated wastewater to 200 litres per second. The mine was fined $51,000 last November for exceeding discharge limits and contravening B.C.’s Environmental Management Act with unauthorized discharge.

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The main source of concern for most onlookers is the proposal to substantially increase the height of an enormous wet tailings impoundment, which sits in a natural valley at the mine’s site. The dam contained about 150 million cubic metres of settled tailings (meaning not saturated) as of Jan. 1, 2019, and is permitted to contain 240 million cubic metres, according to Copper Mountain. The expansion would increase its capacity to 420 million cubic metres of tailings. Mount Polley contained about 44 million cubic metres of tailings, and released about 17 million cubic meters of water and 8 million cubic meters of tailings in the 2014 spill.

“That [dam] has to last forever,” Mitch Friedman, executive director of Conservation Northwest, a non-profit group that focuses on transboundary conservation issues between B.C. and Washington, told The Narwhal. “I mean, literally forever — against seismic activity, climate change, storm events and saturation.”

Copper Mountain Mining Corporation Similkameen Princeton BC

An aerial view of the Copper Mountain mine near Princeton, B.C. Photo: Edgar Bullon / Overflightstock

David Chambers, founder and president of the Center for Science in Public Participation, said tailings dams are typically approved up to a certain height when the project is first sanctioned so the process companies go through to apply for increases up to that height is mostly a formality. 

But Chambers said he would expect to see “a full-blown environmental evaluation” of the company’s proposal to increase the dam’s allowable height at Copper Mountain from 192 metres to 255 metres. 

“That’s almost another 200 feet high. That’s a big deal,” said Chambers, who has 40 years of experience in mineral exploration. “When you build structures that big, you really have to start worrying, ‘can they stand up on their own?’ Are we building something so big that just the weight of the structure itself is going to destroy it?”

Don Strickland, chief operating officer for Copper Mountain Mining Corporation, told The Narwhal the proposed expansion, which would extend the mine’s lifespan by 21 years, does not meet provincial requirements for an environmental assessment. 

Instead, he said the expansion proposal will undergo “a very rigid permit review process,” which requires authorization from multiple provincial ministries.

British Columbia’s Ministry of Energy, Mines and Low Carbon Innovation confirmed the expansion proposal “does not automatically trigger an environmental assessment.” In an emailed response to questions from The Narwhal, the ministry said environment minister George Heyman could call for an environmental assessment if he deems it to be in the public interest. Members of the public can appeal to the minister to do so. 

Strickland said the tailings pond dam was designed by Klohn Crippen Berger — the engineering and geoscience consulting firm that is also co-designing essential components of the Site C dam on B.C.’s Peace River. He added the Copper Mountain facility is designed according to the Canadian Dam Association guidelines and B.C.’s health, safety and reclamation code for mines, adding that the company has done a thorough geotechnical survey. 

“It is about having a good design and understanding the foundation,” Strickland said.

The height of the Copper Mountain tailings pond impoundment compared to the Mount Polley dam, which failed in 2014, and the Shangri-La, the tallest skyscraper in Vancouver. Graph: Carol Linnitt / The Narwhal

The ghost of Mount Polley

The site of the Copper Mountain mine has a long history of mining in B.C.’s mountainous interior. Exploration at the site began in the 1880s and large-scale mining followed in the 1920s. Mining continued on and off under different companies as metal prices fluctuated. The mine eventually shut down in 1996 before being brought to life again in 2007 when the Copper Mountain Mining Corporation began exploratory drilling. In 2009, Mitsubishi Materials Corporation took over 25 per cent ownership of the mine.

The mine site is comprised of a large pit and a tailings pond and treatment facility on the east side of the Similkameen River, and a smaller pit, known as the New Ingerbelle pit, on the west side. The mine covers an area of 67 square kilometres — making it bigger than the town of Princeton, which covers about 48 square kilometres. In 2020, Copper Mountain mined over 14,000 kilotonnes of ore and almost 41,000 kilotonnes of waste rock, for a gross profit of $104.6 million.

The Copper Mountain Mining Corporation is also considering scaling up its production, and has completed a pre-feasibility report to increase extraction from 45,000 tonnes to 65,000 tonnes a day, which is a 44 per cent increase. It estimates the increased production would increase the mine’s worth to $1 billion.

Some say the construction of an even larger tailings impoundment within the river valley presents too great a risk in light of the costly lessons learned at the Mount Polley mine.

The expert panel that examined the cause of the Mount Polley disaster warned that B.C. can expect two dam failures every 10 years, unless mining laws are updated.

Friedman of Conservation Northwest said he finds that statistic deeply worrying when thinking about the Okanogan River and water in Washington. “If one of those things collapsed, just imagine that rolling down the river,” he said in a telephone interview from his home in Seattle. “It’s terrifying.”

The province has a history of lax regulation of the mining industry. In 2016, B.C.’s Auditor General published a scathing report, after investigating whether or not mining compliance and enforcement activities in B.C. were sufficient to protect the province from environmental risks. The report found B.C.’s mines ministry and environment ministry both “lack sufficient resources and tools to manage environmental risks from mining activities.”

“Almost all of our expectations for a robust compliance and enforcement program were not met,” then-Auditor General Carol Bellringer said in a statement at the time.

Read more: In a world that needs metals, how can we mine more responsibly?

The provincial government subsequently established a Deputy Ministers Mining Compliance and Enforcement Board to oversee the Mount Polley expert panel’s recommendations. Last year, the government introduced amendments to B.C.’s Mines Act, creating a chief permitting officer and chief auditor position, in addition to the existing chief inspector of mines. 

But experts like Calvin Sandborn, legal director of the Environmental Law Centre at the University of Victoria, and those with the First Nations Energy and Mining Council, have identified gaps where the province has not yet met recommendations made by the Mount Polley expert panel and are calling for more changes.

“Mining has such a capacity for poisoning an entire watershed forever that we need to do a better job of regulation,” Sandborn told The Narwhal.

The Environmental Law Centre, along with 30 mining advocacy and legal organizations, has called for a prohibition on wet tailings impoundments, unless a risk assessment process can demonstrate wet tailings pose a lower environmental, financial and public safety risk than dry tailings.

In June 2020, an international group of 142 scientists, communities and environment organizations called for a new global standard for tailings facilities, noting that “there are 71 known cases of tailings failures (since 2010) that have led to 482 deaths and damaged over 2,100 kilometres of waterways.”

“Across the world, communities in the shadow of large tailings dams live in a state of perpetual fear,” a report from the group states.

The Copper Mountain mine is located 20 kilometres south of Princeton, B.C. and straddles the Similkameen River. Map: Carol Linnitt / The Narwhal

Robert Edward, former Chief of the Lower Similkameen Band, visited the Mount Polley mine and remembers hearing how the mine’s dam would never fail, shortly before it breached.

“So we always think, it’s not a matter of if, it’s a matter of when this thing comes down,” he said.

When asked about concerns raised by the disaster at Mount Polley, Strickland emphasized the differences between the two mines.

He said the Copper Mountain Mining Corporation has a thorough understanding of the geotechnical characteristics of the tailings management facility, while the Mount Polley failure was caused by an unidentified weak clay layer 10 metres under the dam.

The Copper Mountain dam facility is located within a valley that is generally drier, with lower precipitation and higher evaporation, than the Mount Polley area, he added. He also said the Copper Mountain facility is designed for the probable maximum precipitation.

“It is like building a tall building in the city it is not about the height but about the foundation and the construction design.” 

The facility is designed “for perpetuity,” and climate change and earthquakes have been considered in the engineering, he said. 

Chambers said it is fair to compare the Copper Mountain and Mount Polley mines “but they aren’t exactly the same.” 

“I’m not sure that we really understand all the risks that we’re creating for future generations.”

Mount Polley’s tailings facility was built from waste rock (mined bedrock that had no desirable metals) while Copper Mountain’s is built from tailings (finely ground rock that has been milled, with desirable metals removed).

Chambers said there are also design differences that address potential saturation of the dams, which could make the use of dried tailings unstable.

One significant difference, he said, is that Mount Polley began to “push the engineering to the limit” in raising its dam, while Copper Mountain “seems to be following the basic design.”

But many factors like weather, climate change, water quality and cumulative impacts are inherently hard to predict, he emphasized. 

“What they’re proposing in terms of an expansion on the face of it is not incredibly risky, but these things are risky, inherently. I’m not sure that we really understand all the risks that we’re creating for future generations,” he said.

Similkameen River in the Valley Looking from Keremeos Near Osoyoos BC Canada

The Copper Mountain mine straddles the Similkameen River, and discharges into the river at 60 litres per second. Photo: Edgar Bullon / Overstockflight

Copper Mountain mine out of compliance 31 times since 2015

A consultant hired by Conservation Northwest found that Copper Mountain Mining Corporation has received 31 notices since 2015 for falling out of compliance with B.C. regulations. Twenty-four notices were directly related to unauthorized discharges into the watershed.

The Narwhal reviewed the compliance actions and ran the numbers by the province and the company.

The two most recent penalties were reported by the province on Nov. 12, 2020, when the Copper Mountain mine was fined $51,000 for exceeding its discharge limits and contravening the Environmental Management Act with unauthorized discharge.

A letter to the company from the Ministry of Environment and Climate Change Strategy’s environmental protection division suggests the issue of unauthorized discharge began on Jan. 1, 2019, and was still an issue at an inspection in September 2020.

Strickland blamed miscommunication for the penalty, saying requirements were changed to require discharge to be pumped back to the facility.

“Temporary systems were quickly installed following the September inspection where the miscommunication was identified,” he said.

In terms of the other compliance issues since 2015, Strickland said “there have been minor non-compliance periods for things such as a pump running out of fuel or pumps and pipelines freezing up during winter conditions,” and temporary systems were installed while permanent systems were built.

“This is why you’ve got every U.S. senator from a state bordering Canada complaining.”

The Ministry of Energy, Mines and Low Carbon Innovation said the government will conduct a follow-up inspection in the coming months.

Sandborn, of the Environmental Law Centre, emphasized that mines around B.C. regularly have issues of non-compliance. 

“It’s not unusual to have mines routinely breaking the legal limit [of mining waste discharge],” Sandborn said.

“This is why you’ve got every U.S. senator from a state bordering Canada complaining.”

In 2019, eight American senators wrote a letter to B.C. Premier John Horgan, asking him to address downstream contamination from mines.

Washington State Senator Jesse Salomon collected signatures from 25 state senators and house representatives for a letter to Horgan, sent earlier this month, expressing concern about mining impacts on the Skagit, Similkameen, Okanogan, Kettle and Columbia Rivers, which start in B.C. and flow into Washington.

Cumulative impacts on river preventing access to traditional foods

Along with concerns about a potential tailings pond breach, downstream residents worry that increased discharge from an expanded Copper Mountain dam would increase water pollution and affect traditional food sources. 

Edward said he has witnessed the cumulative impacts of industry, like mining and logging, on the Similkameen. He has seen the river change since he was young, becoming warmer, less clear and developing a “sludge,” while fish became “mushy.” 

When he began to learn about selenium, phosphates and other contaminants from industry, Edward stopped fishing in the river entirely.

“I’m not a biologist. But I noticed a change,” he said. “Prior to that, we’d fill up freezers with all kinds of fish … I don’t even swim in the river anymore. I don’t drink water from the river anymore … I don’t feed my family [from that river].”

The lack of access to traditional foods has been “devastating” for the community, he said. He has seen higher rates of cancer, diabetes and heart disease.

“It’s not good for us because we lose out on our food. There’s economic gain for some people, a lot of our people work up there … which is great, you know, more power to them,” he said. “You got to make money somewhere. But it’s really hard to find balance in the devastation we feel and see on our territories.”

The cumulative impacts of industrial development on the Similkameen River have also affected the Confederated Tribes of the Colville Reservation. Their territory extends across Washington, B.C. and Idaho, but the Tribes were largely restricted to Washington state by colonial governments in the 20th century.

Rodney Cawston, chairman of the Confederated Tribes, said data shows groundwater is frequently not up to tribal drinking water standards due to contaminants often associated with industry. He said the Colville Tribes have put a lot of time and money into restoring fish habitat along the Okanogan and Columbia Rivers, and he’s concerned increased mining activity will negate their efforts.

“I cannot see how the expansion could be done safely. There’s just too high a probability for pollution or contamination,” Cawston said in an interview. “It seems inevitable.”

Like many Indigenous Peoples, Cawston’s family members were confined to reserves by colonial governments. Cawston’s grandmother, who was Sinixt, and his grandfather, who was Okanagan, were forcibly relocated down to the United States. But the Okanagan Nation Alliance and the Colville Tribes are closely intertwined and share relatives. Rick Desautel, a member of the Arrow Lakes Tribe, took a case to the Supreme Court of Canada fighting for the federal government to recognize that the Sinixt hold Aboriginal Rights in Canada — and won

“Even though we’re now here in the United States, these are still our ancestral homelands,” Cawston said. 

The cumulative impacts of industry, including hydro dams that blocked fish passage, have also affected the Colville Tribes’ access to food. The Grand Coulee Dam, which led to the loss of 1,770 kilometres of salmon and steelhead habitat, has for decades prevented fish from swimming to the upper reaches of the Columbia River. 

“If we don’t stop at some point, we’re going to get to a point of no turning back,” Cawston said. “We have to look at what we’re doing today for our future generations to have clean water and these other resources we’ve taken advantage of.”

Strickland said the tailings at Copper Mountain are not acid-generating and the discharged water “is very high quality and does not require treatment.” 

But Chambers said other problems can arise. He said it can take longer to see the impacts of contaminants like arsenic and selenium, and sometimes the impacts are not apparent until the mine stops diluting the tailings pond.

Long-term exposure to arsenic in drinking-water leads to increased risks of cancer and skin conditions in humans. Arsenic and selenium also impact aquatic life, causing birth defects in fish. Mining discharge can increase levels of other water contaminants like cyanide, nitrate and sulphates, which have the potential to impact aquatic life, invertebrates and human life.

Strickland said there is no negative impact from the discharge at the mine, according to the company’s modelling.

“Our discharge water quality is excellent, it is drinking water quality,” he said.“We are fully committed to protecting the pristine water of the Similkameen River.”

The Copper Mountain mine is located within the traditional territory of the Upper and Lower Similkameen Indian Bands. Both bands have impact benefit agreements with Copper Mountain Mining Corporation and Strickland said the company is working closely with them. Neither of the bands were able to provide comment to The Narwhal before publication.

Government needs more transparency around compliance, experts say

Sandborn also said B.C. needs to be more transparent and information on compliance needs to be more publicly available.

“There’s a whole bunch of non-compliances that do not wind up being posted publicly, which is a bit of an outrage,” he said. “It’s very important for the public to know the scope.”

Calvin Sandborn

Calvin Sandborn, legal director of the Environmental Law Centre at the University of Victoria, told The Narwhal B.C. needs to increase transparency surrounding non-compliance at mines. Photo: Taylor Roades / The Narwhal

Danielle Droitsch, the consultant hired by Conservation Northwest, agreed compliance information needs to be more easily available. She said she and her colleague combed multiple databases and reports to get a more complete view of compliance at Copper Mountain. They are not confident they found everything. 

“It’s astonishing what lengths we had to go through to just answer the basic question of compliance at this mine,” she said.

Edward said he wants to see data shared in a more intelligible way. He said that when he requested information on water quality in the Similkameen close to his community, he received a pile of raw data that would require scientific expertise to make sense of.

“It could be Italian for all I know,” he said wryly. “But I can’t read it because I’m not a technical person, and we don’t have the money to hire a technical person.”

A large number of British Columbians support mining reform, according to a recent poll published in the fall of 2020 by the BC Mining Law Reform Network and the non-profit conservation group Northern Confluence. Eighty-one per cent of people surveyed said the province should “modernize land-use plans with communities and First Nations to ensure the protection of water quality and fish habitat,” while 84 per cent said mining companies “should be required to get permission from private landowners, municipalities and First Nations before doing any business on their lands.” 

In addition to increased transparency, Sandborn said remediation costs companies are expected to put up in advance need to be increased. The province currently calculates a mine’s liability estimate and asks companies to put up bonds. According to the 2019 annual report from the Chief Inspector of Mines, the province estimated Copper Mountain’s liability at $14.8 million, and the company has put up $20.9 million — putting them a step ahead of many companies that have not put up their full bond.

But Sandborn said B.C.’s calculations need to be updated.

“A single water treatment plant could be more than $25 million,” he said. “This is something we’ve been calling for a long time — raising those bonds.”

The Tulsequah Chief mine — which has been leaking contaminated water into a salmon watershed on the B.C.-Alaska border for over 60 years — will cost $48.7 million to clean up, and it’s still unclear who will foot the bill.

And disasters are much more expensive — the Mount Polley tailings pond collapse cost Imperial Metals $67 million, and B.C. citizens shouldered an additional $40 million in cleanup costs. 

“It’s a huge issue, getting realistic bonding, because that’s where the actors are going to be on the hook,” Sandborn said.

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