Alberta’s highest court has overturned regulatory approvals for a $440-million oilsands mine that would have encroached on land a local First Nation considers sacred.

The Court of Appeal says the Alberta Energy Regulator’s refusal to consider concerns from the Fort McKay First Nation violated the honour of the Crown.

The band is surrounded on three sides by oilsands development and says the Moose Lake area in northern Alberta is the last place members can go to practice their traditional rights.

Photo credit: File

The band had been negotiating with the province for two decades over the area and thought it had a deal in 2018 for a 10-kilometre buffer.

But that same year, the regulator approved Prosper Petroleum’s Rigel project, a 10,000-barrel-a-day oilsands mine that would have come within two kilometres of it.

The lake is the subject of ongoing talks between industry, the band and the province — and Chief Mel Grandjamb has said a deal is close.

The court says the regulator should have taken those talks into consideration before granting its approval.