Contents from a tailings pond spill down Hazeltine Creek into Quesnel Lake near the town of Likely, B.C., in August, 2014.JONATHAN HAYWARD/The Canadian Press
Imperial Metals Corp. III-T is facing charges of violating the federal Fisheries Act stemming from a tailings dam spill at a British Columbia mine that caused massive damage to trees and polluted local waterways.
In August, 2014, a catastrophic tailings dam failure at the Mount Polley copper and gold mine resulted in about 25 million cubic metres of waste water and materials spilling into local waterways. The mine is located in B.C.’s Cariboo Region near Quesnel Lake, about 400 kilometres northeast of Vancouver.
Vancouver-based Imperial said in a release that the company, along with its subsidiary, Mount Polley Mining Corp., and engineering firm Wood Canada Ltd. were indicted in the Supreme Court of British Columbia on Friday.
Fisheries and Oceans Canada, Environment and Climate Change Canada, and the British Columbia Conservation Officer Service had been jointly investigating Imperial over possible contraventions of the federal Fisheries Act. In a statement on Tuesday, the B.C. Conservation Officer Service said that 15 charges had been laid against the company. The first court hearing is scheduled for Dec. 18.
The Mount Polley spill is considered one of the worst environmental disasters in the Canadian mining industry, with hundreds of tonnes of arsenic, lead and copper spilling into nearby lakes.
A drinking water ban was in effect for residents in the area of the spill for nine days. Testing on fish after the spill showed elevated levels of arsenic, copper and zinc. The longer-term impact on fish and wildlife is still being debated.
In the years after the spill, an investigation by the B.C. government in conjunction with external independent engineers and consultants determined the collapse was caused by many factors, including a weak foundation, design problems with the dam, poor on-site monitoring by Imperial and its consultants, and inadequate management of water buildup.
The B.C. government made revisions to its mining code in the years after the accident, including rolling out new design standards for tailings storage facilities.
The collapse forced Imperial to suspend operations at Mount Polley for almost two years amid the remediation effort.
Scott Dunbar, professor with the department of mining engineering at the University of British Columbia, said in an interview that most of the damage from the tailings’ failure was the physical destruction of trees as well as sediment deposited in Quesnel Lake.
“The ability for fish to lay eggs and feed was hampered,” he said.
By 2016, Imperial had spent more than $70-million on remediation and restoration work, including planting about 30,000 trees and shrubs.
Prof. Dunbar said that the accident also illustrated the weakness in the current system of oversight over tailings dams that sometimes prevents companies from discharging a buildup of water because regulators won’t always allow it.
“At Mount Polley, there was a lot of water accumulating. They knew that. They couldn’t release it. They weren’t allowed to,” he said.
“It’s the way it works worldwide. And it’s just a lack-of-management nightmare.”
While ecological disasters of the scale of Mount Polley are rare in Canada, an accident earlier this year in Yukon bore some similarities.
Four million tonnes of cyanide-laced rocks collapsed at an outdoor gold-processing facility at the Eagle gold mine operated by Toronto-based Victoria Gold Corp. in late June, causing massive damage to mine infrastructure and contamination. About two million tonnes of contaminated materials broke through the company’s containment zone and spilled into the local environment, killing fish and raising concerns about groundwater pollution.
The company was placed into receivership in August with shareholders getting completely wiped out. PricewaterhouseCoopers Inc. took over the environmental mitigation effort and the Yukon government is now responsible for funding the cleanup, which was pegged at $150-million. Eagle is situated on the traditional territory of the First Nation of Na-Cho Nyak Dun, and is located about 375 kilometres north of Whitehorse.