Even after the mine closed in 1974, it remained one of the largest point sources of metal pollution to the marine environment in North America. Tailings and waste rock were used to fill in the shoreline, and Britannia Creek, containing kilograms of copper, flowed clear but devoid of life into Howe Sound, killing ocean life for at least two kilometers along the shore. Britannia Creek’s water was so toxic at the mine’s closing that Chinook salmon fry, when introduced, died within forty-eight hours.
