FILE - In this April 13, 2006 file photo, Pete Vavricka conducts an underground train from the entrance of Yucca Mountain in Nevada. The nuclear crisis in Japan has laid bare an ever-growing problem ... more 
FILE - In this April 13, 2006 file photo, Pete Vavricka conducts an underground train from the entrance of Yucca Mountain in Nevada. The nuclear crisis in Japan has laid bare an ever-growing problem for the United States _ the enormous amounts of still-hot radioactive waste accumulating at commercial nuclear reactors in more than 30 states. The U.S. has nearly 72,000 tons of the stuff, according to state-by-state numbers obtained by The Associated Press. But the nation has no place to permanently store the material, which stays dangerous for tens of thousands of years. less 
1 / 1
Associated Press | Photo By Isaac Brekken, File
Tue, Mar 22, 2011 5:22 PM EDT