By Lindsey Bever and Steven Mufson May 9 at 12:59 PM
In this July 9, 2014 file photo, a sign informs visitors of prohibited items on the Hanford Nuclear Reservation near Richland, Wash. An emergency has been declared Tuesday, May 9, 2017, at the Hanford Nuclear Reservation after a portion of a tunnel that contained rail cars full of nuclear waste collapsed. (AP Photo/Ted S. Warren, File)
Hundreds of workers at the Hanford nuclear waste site in Washington state have been ordered to (...)