Teck Resources treated the Columbia River as a free waste disposal system for decades, said a Washington state judge who has ruled the Canadian company is liable for the cost of cleaning up the contamination of the river south of the border.In a decision announced late Friday, Judge Lonny Suko ruled that, "for decades Teck's leadership knew its slag and effluent flowed from Trail downstream and are now found in Lake Roosevelt, but nonetheless Teck continued discharging wastes into the Columbia River."Suko noted an admission from the company that it "had been treating Lake Roosevelt as a 'free,' 'convenient' disposal facility for its wastes."The decision gives the U.S. Environmental Protection Agency the ability to force Teck to pay for the clean-up, and potentially for any ongoing damages and losses that result from the ongoing contamination. That issue has yet to be determined by the court.Suko found that from 1930 to 1995, Teck intentionally discharged at least 9.97 million tons of slag that included heavy metals such as lead, mercury, zinc and arsenic.The judge also found that Teck knew the hazardous waste disposed of in the Columbia River was likely to cause harm."We are very pleased with this outcome," John Sirois, chairman of the Colville Business Council, said in a statement. "Now that the Court has found that Teck is liable for its contamination of the Columbia River, we look forward to its participation in cleaning it up and paying for any resulting damages."The company said Friday that the amount of those costs will be determined in a subsequent phase of the case.