Last August, on a visit to Alaska, Secretary of State John Kerry addressed the issue: “Downstream impacts should not be taken lightly by any country anywhere.” But when Alaska’s lieutenant governor, Byron Mallott, visited Washington to ask that the International Joint Commission examine the problem, he returned saying that State Department officials told him that this was a local issue.

Concerns about these mining projects are not new. In November 2011, a group of 36 scientists wrote an open letter to Christy Clark, the premier of British Columbia, warning of the environmental impact of the province’s mining industry. They predicted that “habitat for salmon and other wildlife will be destroyed” and that additional effects would include “altered flow and temperature patterns, disturbance to wildlife interacting with roads, and reduced water quality associated with sedimentation and acid mine drainage.”

Three years later, in August 2014, a tailings dam at the Mount Polley mine in British Columbia failed. A volume of water equivalent to thousands of Olympic-size swimming pools, laden with sediment and heavy metals, washed away Hazeltine Creek and dumped into Quesnel Lake, a key salmon spawning ground of the Fraser River watershed. According to Jacinda Mack, a member of the Secwepemc Nation, located downriver from Mount Polley, the following summer was the first time in thousands of years that native tribes didn’t gather sockeye salmon, because of concerns over metal in fish tissue. The episode is now considered one of the worst mining spills in North American history.

An independent investigation funded by the government of British Columbia uncovered flaws in how the dam at the Mount Polley mine was built, maintained and operated, and recommended against using similar tailings facilities. The government publicly stated that the recommendations would be implemented. However, shortly after the release of the report, Imperial Metals, the owner of the Mount Polley mine, received a provincial permit to operate an open-pit mine called Red Chris, with a facility similar to that of Mount Polley — except this one was larger, built to contain highly toxic acidic tailings, and made use of an existing freshwater trout lake. So long, trout.