WASHINGTON — Americas nuclear power industry needs to do a better job of planning for rare but catastrophic events such as the Fukushima disaster in Japan, according to a panel of scientists whom Congress asked to make recommendations for nuclear safety.
While nuclear design rules have focused on withstanding more predictable problems, its the highly unusual but extreme events that have caused the worst accidents in recent decades, such as Chernobyl in 1986, Three Mile Island in 1979 and Fukushima three years ago. More can be done to plan for such events, according to the report released Thursday by the National Academy of Sciences.
Current approaches for regulating nuclear plant safety are clearly inadequate for preventing core-melt accidents and mitigating their consequences, concluded the authors of the report, who include a panel of prominent nuclear scientists, physicists and engineers.
The U.S. nuclear industry has been struggling to compete with other sources of energy on the basis of cost as well as local opposition over safety concerns. The average age of U.S. reactors is about 33 years. Two began commercial operations in 1969, the year John Lennon married Yoko Ono and Neil Armstrong became the first person to walk on the moon. Four shut down last year, and the only new reactors under construction in the country are in the Southeast: South Carolina, Georgia and Tennessee.
The Fukushima disaster hit the industry hard around the world, just as nuclear energy was poised to make inroads in a world increasingly concerned with global warming from fossil fuels. The accident has left Japan scrambling to find other sources of energy and Germany pledging to phase out nuclear by 2021. Other nations are slowing their construction of nuclear plants as they review safety rules, the International Energy Agency said, although it expects China, South Korea, India and Russia to lead a future nuclear resurgence.
Congress told the National Academy of Sciences to look at what the U.S. can learn from the Fukushima accident in order to keep nuclear power viable in the U.S. The disaster began when an earthquake and tsunami hit the Japanese power plant, leading to a loss of power at the facility and a release of radiation into the atmosphere and ocean. The scope of the disaster went beyond the nuclear industrys usual emergency planning, said Kevin Crowley, who directed the National Academy of Sciences study of the incident.
He said most risk assessments considered how to respond to a problem in a unit within a nuclear facility. But in Fukushima all six units were affected.
Resources were stretched thin; staff were stretched thin. Those kinds of things havent traditionally been considered in risk assessments, Crowley said.
The National Academy of Sciences said regulations required nuclear plants to be designed to withstand certain hypothetical events. Massive and highly unusual problems such as Fukushima and Chernobyl went further, and are known as beyond-design-basis accidents.
There is a need to better understand the safety risks that arise from such events and take appropriate countermeasures to reduce them, the report said.
The American nuclear industrys main trade group said steps had already begun, under the direction of the U.S. Nuclear Regulatory Commission, to learn from the Fukushima disaster and be ready for such extreme events that might exceed a plants design.
Simply put, we cannot let such an accident happen here, said Anthony Pietrangelo, a senior vice president at the Nuclear Energy Institute.
He said the new measures included the industrys FLEX initiative, meant to provide backup power and water to a nuclear plant after such an event.
The National Academy of Sciences report said it was too soon to evaluate the effectiveness of such efforts. That disappointed Dave Lochbaum, the director of the Nuclear Safety Project at the Union of Concerned Scientists, who said the academy could have made an effort.
I thought thats what they were tasked with doing, Lochbaum said. They punted that down the road.
The National Academy of Sciences panel also said it didnt have the time or resources to take a deep look at U.S. preparedness for severe nuclear accidents.
Nevertheless, the accident raises the question of whether a severe nuclear accident such as occurred at the Fukushima Daiichi plant would challenge U.S. emergency response capabilities because of its severity, duration and association with a regional-scale natural disaster, the report said.