Workers at the Hanford Nuclear Reservation near Richland, Wash., are on duty at an underground tank farm where highly radioactive waste is stored on July 14, 2010. (AP Photo/Shannon Dininny)

Photo by: Shannon Dininny

Workers at the Hanford Nuclear Reservation near Richland, Wash., are on duty at an underground tank farm where highly radioactive waste is stored on July 14, 2010. (AP Photo/Shannon Dininny)