A federal appeals court in Montgomery is considering a case involving the Birmingham-based Drummond Coal and three killings that happened in South America more than a decade ago. A panel of the 11th U.S. Circuit Court of Appeals is scheduled to hear arguments Thursday that could revive a federal lawsuit over the slayings. Children of slain three coal miners filed suit in 2009 claiming Drummond hired paramilitary gunmen to kill their fathers near its Colombian coal mine in 2001. The men were union leaders.