In early June, the U.S. Supreme Court declined to hear an appeal by Teck Inc. of the case brought forward by the Colville Confederated Tribes (CCT) in Washington. The case involved Teck’s lead-zinc smelter in Trail, British Columbia, and its pollution of the Columbia River and Lake Roosevelt in Washington.

The decision to not hear Teck’s appeal leaves a previous ruling in place, awarding more than $8 million in legal costs to the tribes. It also makes Teck responsible for cleaning up the damage from decades of pollution.

Teck claimed the U.S. courts lacked jurisdiction over the company, but the Ninth Circuit found it “inconceivable” that Teck didn’t know its waste was aimed at Washington when discharge flowed directly into the Columbia River a few miles upstream from the U.S.

The U.S. border is about 15 kilometers (km) from the smelter and Teck was essentially accused of using the Columbia River as a toxic discharge system by flushing away slag and heavy metals that blackened beaches downstream.

The tribes argued that Teck should be found liable under the Comprehensive Environmental Response, Cleanup, and Liability Act (CERCLA).

Teck maintained it has spent millions of dollars cleaning up the Columbia River and a Canadian company should not be held liable under the CERCLA.

The tribes also prevailed in its effort to establish that Teck has “joint and several” liability for damages caused by its waste, meaning Teck will be responsible for all damages regardless of whether others may have also contributed to the harm.

“This decision brings the tribes’ more than 20-year legal battle with Teck to a close,” Rodney Cawston, chairman of the Colville Business Council, said. “We are very grateful for this result, that the highest court in the land agrees that Teck is liable for the enormous damage it inflicted on our river.”

Cawston said Teck released nearly 10 million tons of toxic slag over nearly a century from its smelter.