The Commission on Environmental Co-operation says Canada has failed to counter evidence that it's turning a blind eye when it comes to toxic leakage from the industry's massive tailings ponds.
Canada has maintained the commission doesn't have the right to investigate the issue.
The move sets up a second fight between Canada and the commission, which was set up to ensure free trade doesn't create downward pressure on environmental enforcement.
Next Tuesday is a deadline for the three countries in the commission to decide if it will investigate how Canada protects wild salmon stocks from disease.
Canada has already said it won't take part in the vote.