Nuclear energy issues facing Congress include power plant safety and regulation, radioactive waste management, research and development priorities, federal incentives for new commercial reactors, nuclear weapons proliferation, and security against terrorist attacks. The earthquake and resulting tsunami that severely damaged Japan's Fukushima Daiichi nuclear power plant on March 11, 2011, raised questions in Congress about the disaster's possible implications for nuclear safety regulation, U.S. nuclear energy expansion, and radioactive waste policy. The tsunami knocked out all electric power at the six-reactor plant, resulting in the overheating of several reactor cores, loss of cooling in spent fuel storage pools, major hydrogen explosions, and releases of radioactive material to the environment. The Nuclear Regulatory Commission (NRC) issued orders to U.S. nuclear plants March 12, 2012, to begin implementing safety improvements in response to Fukushima. Significant incentives for new commercial reactors were included in the Energy Policy Act of 2005 (EPACT05, P.L. 109-58), such as tax credits and loan guarantees. Together with volatile fossil fuel prices and the possibility of greenhouse gas controls, the federal incentives for nuclear power helped spur renewed interest by utilities and other potential reactor developers. License applications for as many as 31 new reactors have been announced, and NRC issued licenses for four reactors at two plant sites in early 2012. However, falling natural gas prices and other circumstances have made it unlikely that many more of the proposed nuclear projects will move toward construction in the near term. DOE's nuclear energy research and development program includes advanced reactors, fuel cycle technology and facilities, and infrastructure support. The Obama Administration's FY2013 funding request totals $770.4 million, which is $88.3 million (10.3%) below the enacted FY2012 funding level. DOE is requesting $65 million for FY2013 to provide technical support for licensing small modular light water reactors (LWRs), $2 million below the FY2012 funding level. The House-passed version of the FY2013 Energy and Water appropriations bill (H.R. 5325) increased nuclear R&D by $89.9 million from FY2012, while the Senate Appropriations Committee recommended a $20.1 million increase (S. 2465). Disposal of highly radioactive waste has been one of the most controversial aspects of nuclear power. The Nuclear Waste Policy Act of 1982 (P.L. 97-425), as amended in 1987, required DOE to conduct a detailed physical characterization of Yucca Mountain in Nevada as a permanent underground repository for high-level waste. The Obama Administration decided to "terminate the Yucca Mountain program while developing nuclear waste disposal alternatives," according to the DOE FY2010 budget justification. Alternative waste management strategies were evaluated by the Blue Ribbon Commission on America's Nuclear Future, which issued its final report to the Secretary of Energy on January 26, 2012. The report recommended options for temporary storage, treatment, and permanent disposal of highly radioactive nuclear waste, along with an evaluation of nuclear waste technologies. It did not recommend specific sites for new nuclear waste facilities or evaluate the suitability of Yucca Mountain. No funding was provided in FY2012 or requested for FY2013 to continue NRC licensing of the Yucca Mountain repository, although the issue is currently the subject of a federal appeals court case. The House-passed FY2013 Energy and Water bill provided DOE with $25 million to resume Yucca Mountain licensing, along with $10 million for NRC. The Senate Appropriations Committee authorized a pilot program to develop one or more voluntary nuclear waste storage sites.