Imperial Metals Corporation and its subsidiary Mount Polley Mining Corporation, along with engineering firm Wood Canada Limited, have been charged with violations of Canada’s federal Fisheries Act. The charges stem from the catastrophic failure of the Tailings Storage Facility (TSF) at the Mount Polley Mine in British Columbia in August 2014, which released millions of cubic meters of wastewater and toxic materials into nearby waterways.

The charges were formally outlined in an indictment filed with the Supreme Court of British Columbia on December 6, 2024. The legal proceedings relate to alleged harm caused to fish habitats and waterways in the region, which are protected under the Fisheries Act.

In response to the charges, Imperial Metals issued a brief statement, confirming receipt of the indictment. The company indicated that, given the ongoing legal process, it would refrain from making any further public comments at this time.

Wood Canada Limited, an engineering firm involved in the design and oversight of the Mount Polley tailings facility, is also named in the charges. The firm has not yet issued a statement regarding the charges.

In August 2014, the Mount Polley mine in British Columbia, a major copper-gold operation, experienced the catastrophic failure of its tailings storage facility (TSF). The failure released approximately 25 million cubic meters of wastewater and tailings into nearby Hazeltine Creek. The mine that processed about 22,000 tonnes of ore daily, was forced to suspend operations for a year following the breach and resumed in June 2016. The TSF that covered 2.4 km², consisted of three embankments, with the Main Embankment being the largest. The dam's height had been increased in nine stages, reaching 40 meters before the collapse. Approval was being sought for a further height increase just prior to the failure.

The disaster created Canada’s largest environmental mining incident, contaminating Polley Lake, Hazeltine Creek, and Quesnel Lake, a vital fishery for sockeye salmon and other species. The tailings spill caused a sediment plume that altered the water quality, increasing turbidity and temperature in the affected lakes.

The disaster prompted significant public outcry and led to extensive environmental investigations. A 2015 inquiry concluded that the failure was the result of several design and operational shortcomings, including inadequate monitoring and risk management procedures. Since the incident, both Imperial Metals and the provincial government have faced ongoing scrutiny for their roles in the disaster and response efforts.

The charges now filed by federal authorities under the Fisheries Act carry serious legal consequences. If found guilty, the companies involved could face substantial fines and penalties, as well as potential reputational damage. The case is expected to have wide-reaching implications for environmental accountability in the Canadian mining sector.