A portion of a storage tunnel that contains rail cars full of radioactive waste collapsed Tuesday morning, forcing an emergency declaration at the Hanford Nuclear Reservation in southeastern Washington state. The U.S. Department of Energy said the Tuesday collapse covered about 400 square feet (37.1 square meters) instead of the 16 square feet (1.4 square meters) first reported at the Hanford Nuclear Reservation. Officials detected no release of radiation and no workers were injured, said Randy Bradbury, a spokesman for the Washington state Department of Ecology.