British Columbia has approved a permit amendment allowing Imperial Metals to expand operations at the Mount Polley copper-gold mine in the province’s south-central region. 

“Receiving this permit…[means] we will be able to continue to provide good jobs and economic opportunities for the region,” said Brian Kynoch, president of Imperial Metals in an Aug. 29 release. “We will also continue to develop our exploration and mine planning to look for opportunities for further extension of the mine life.” 

The expansion will extend Mount Polley’s life to 2033. Modifications to the mine plan involve deepening the existing Springer pit, enlarging rock-disposal areas and isolating potentially acid-generating materials in the old Cariboo pit upon closure. The company would also continue to treat water and release it into Quesnel Lake in accordance with regulatory permits. 

The expansion approval followed a joint review of technical reports, regulatory input and First Nations consultations to ensure compliance with B.C.’s environmental and safety standards, said Imperial Metals. However, further amendments under the Mines Act and the Environmental Management Act – which are also necessary for the planned expansion to advance – are still pending.  

B.C.’s environment minister Tamara Davidson and mining minister Jagrup Brar concluded that the expansion is unlikely to cause significant effects since the work will remain within the mine’s existing footprint. They also noted that any impacts can be managed through mitigation measures already required by permitting.  

Mount Polley is the site of one of Canada’s most severe mining-related environmental disasters in 2014, when a tailings dam collapse released roughly 25 million cubic metres of tailings and wastewater into nearby waterways 

In July 2015, the B.C. government granted Imperial Metals a conditional permit to resume limited operations at Mount Polley. A year later, the mine was authorized to return to full production. Mine operations were later paused in 2019 due to declining copper prices and resumed at full capacity in 2022. 

According to Imperial Metals' production update for the second quarter of this year, the mine produced 9.496 million pounds of copper and 11,061 ounces of gold. 

Pushback on tailings expansion 

The provincial permit approval comes as Imperial Metals faces ongoing opposition from the Xatśūll First Nation over a planned raise of the Mount Polley mine’s tailings storage facility. The nation sought to overturn the provincial approvals issued on March 27 allowing the facility to be raised to 974 metres, up from its previous height of 970 metres. The Xatśūll First Nation argues that this should have triggered a new environmental assessment and that First Nation’s consultation was inadequate. 

On Aug. 6, the B.C. Supreme Court dismissed the Xatśūll First Nation’s challenge, finding the consultation process sufficient. This week, the Xatśūll First Nation filed an appeal to the B.C. Court of Appeal, seeking to overturn the ruling.