The U.S. Supreme Court has refused to hear an appeal from a Canadian mining company in a cross-border pollution case, in effect sustaining an earlier appeals court ruling holding the company liable for pollution under U.S. law. Just 10 miles north of the U.S. border in British Columbia, the mining company Teck Cominco has been operating a smelter that from 1892 until 1994 dumped toxic mining waste into the Columbia River that drains into the United States. Members of the Colville Confederated Tribes and later the state of Washington sued under the U.S. Superfund law seeking study and cleanup. Teck argued that as a Canadian company operating in Canada, it wasn’t liable for polluting the United States. But last year an appeals court ruled that the company was indeed responsible for some cleanup costs; the company then appealed to the U.S. Supreme Court to block the ruling. Now that the Supremes have refused to hear the appeal, Teck and other cross-border polluters can be held responsible. The National Mining Association and the U.S. Chamber of Commerce sided with Teck, fearing Canadian retaliation that could hold U.S. businesses liable for polluting Canada. And we wouldn’t want that.