FILE - In this Jan. 14, 2013 file photo provided by the Nuclear Regulatory Commission, Alison Macfarlane, second from right, the chair of the Nuclear Regulatory Commission, listens to R

 

              FILE - In this Jan. 14, 2013 file photo provided by the Nuclear Regulatory Commission, Alison Macfarlane, second from right, the chair of the Nuclear Regulatory Commission, listens to R
FILE - In this Jan. 14, 2013 file photo provided by the Nuclear Regulatory Commission, Alison Macfarlane, second from right, the chair of the Nuclear Regulatory Commission, listens to Richard St. Onge, director of Nuclear Regulatory Affairs for Southern Cal Edison, third from right, speak during a tour of the troubled San Onofre Nuclear Power Station in San Juan Capistrano, Calif. As the Monday, March 11, 2013, two-year anniversary approaches of the earthquake and tsunami that crippled Japan's Fukushima Dai-ichi nuclear plant, U.S. regulators, safety advocates and the industry are debating whether safety changes imposed after the disaster have made the nation's 65 nuclear plants safer. (AP Photo/Nuclear Regulatory Commission, File)