The issues of environmental liabilities and pension deficits of U.S. Steel Canada Inc. must be settled during the current bankruptcy protection process, says one of the potential buyers of the steel maker. Those are key issues that were kicked down the road during the trip that Stelco Inc. made through creditor protection in the 2000s before United States Steel Corp. bought Stelco in 2007, said Tom Clarke, a Virginia health-care executive and environmental activist whose ERP Compliant Fuels has made a bid to buy U.S. Steel Canada.