Clay Mullins (left), brother of mine disaster victim Rex Mullins, listens as Upper Big Branch miner Stanley "Goose" Stewart tells the House Education and Labor Committee that the mine "was a ticking time bomb" because of problems with ventilation and explosive methane and coal dust. Jon C. Hancock/AP hide caption

itoggle caption Jon C. Hancock/AP

Mine workers stand at the entrance of the Upper Big Branch coal mine on April 9, a few days after an explosion killed 29 men. Matt Sullivan/Getty Images hide caption

itoggle caption Matt Sullivan/Getty Images