Teck Metals, approximately 10 river miles upstream of the international border, was the primary source of the pollution in the upper Columbia, according to the EPA.

The District of Columbia sued the federal government Friday over pollution in the Anacostia River that the city says comes from over a century of agencies using the waterway as a “dumping ground ...

Federal officials on Friday declared portions of the Upper Columbia River a Superfund site after decades of studying, debating and litigating over the pollution that primarily washed downriver ...

From 1906 to 1996, Teck dumped 450 tons of slag a day into the Columbia River. Slag is a solid discharge made up of heavy metal toxins. And it all carried downstream, across the border, to Northport.

Toxic forever chemicals discovered at a SC closed textile plant threaten the Broad River about 60 miles upstream from Columbia’s canal drinking water plant.