The British Columbia government has approved a plan to raise the tailings dam at the Mount Polley copper-gold mine, 12 years after a catastrophic breach sent millions of cubic metres of mining waste into Quesnel Lake and surrounding waterways.
Approval Details
The decision, announced Wednesday by the Ministry of Energy, Mines and Low Carbon Innovation, allows Imperial Metals to increase the height of the tailings storage facility. The company must meet 38 legally binding conditions, including enhanced monitoring and groundwater management, before construction can begin.
According to the ministry, the new dam will be built using a 'downstream' construction method, considered more stable than the upstream method used for the original dam that failed in 2014. The breach released an estimated 24 million cubic metres of tailings and water into Hazeltine Creek, Polley Lake, and Quesnel Lake.
Environmental and Community Concerns
The approval has drawn criticism from environmental groups and local First Nations. The Soda Creek Indian Band (Xatśūll First Nation) and the Williams Lake Indian Band have both expressed concerns about the long-term safety of the site. 'We are deeply disappointed that the province has approved this without a full independent review,' said Chief Willie Sellars of the Williams Lake Indian Band in a statement. 'Our people still bear the scars of the 2014 disaster.'
Environmental group MiningWatch Canada called the decision 'premature' and noted that the mine has been under a remediation plan since the breach. 'Approving a higher dam before the site is fully remediated sets a dangerous precedent,' said spokesperson Jen Gobby.
Economic and Regulatory Context
Imperial Metals has argued that the expansion is necessary to extend the mine's life and support local jobs. The mine, located near Likely, B.C., employs about 300 workers. The company says the new dam will meet or exceed all current safety standards, including those for a 'probable maximum flood' and a 'maximum credible earthquake.'
The province's chief inspector of mines conducted a technical review and recommended approval with conditions. The ministry stated that the decision 'balances economic benefits with environmental protection and reconciliation with Indigenous peoples.'
The 2014 Mount Polley disaster was one of the largest mining spills in Canadian history, prompting a review of tailings dam regulations nationwide. In 2015, a provincial inquiry found that the dam failure was caused by a weak foundation layer, not design flaws, but criticized the company's oversight and the province's regulatory regime.
