Managers at the Environmental Protection Agency were aware of the possible risk for a catastrophic “blowout” at an abandoned mine that could release “large volumes” of wastewater laced with toxic metals, according to internal documents released late Friday. EPA released the documents following weeks of prodding from news organizations like The Associated Press. EPA and contract workers accidentally unleashed 3 million gallons of contaminated wastewater on Aug. 5 as they inspected the idled Gold King Mine near Silverton, Colorado. Among the documents is a June 2014 work order for a planned cleanup that noted that the old mine had not...