FILE - In this Wednesday, March 28, 1979 file photo, a Pennsylvania state police officer and plant security guards stand outside the closed front gate to the Metropolitan Edison nuclear power plant on Three Mile Island near Harrisburg, Pa. after the plant was shut down following a partial meltdown. The plant's cooling towers are seen in the background. The U.S. government has adopted the first set of comprehensive changes in the emergency planning program for communities near nuclear power plants since its creation after the Three Mile Island accident in 1979. In revisions which went into effect on December 2011, the U.S. government is allowing communities within 50 miles of nuclear power plants to practice less often for major accidents and is recommending that far fewer people who live nearby be evacuated immediately. Under new emergency planning rules, federal regulators also are ending a requirement that emergency personnel always practice for a release of radiation. (AP Photo/Paul Vathis)