Nine power units at three Japanese nuclear plants are under states of emergency following last week’s earthquake and tsunami. All are along the eastern coast, north-northeast of Tokyo.
Sources: The Associated Press, International Nuclear Safety Center, Tokyo Electric Power Co.
By Frank Pompa, USA TODAY
In the world of nuclear power, it turns out the "worst-case scenario" wasn't bad enough.
AP/DigitalGlobe
The concept of the worst case underpins everything from the way reactors are designed to the way emergency response plans are crafted. Now it's being redefined in the scramble to avert massive radiation releases from crippled reactors in Japan. When the radioactive steam and smoke have cleared, engineers, regulators and policymakers in the United States and across the globe will have a new reference point in the debate over how to build and operate nuclear power plants — or whether to have them at all.
"This was a wake-up call for anyone who believed that, after 50 years of nuclear power in this world, we have figured it out and can go back to business as usual," said Mark Hibbs, a senior associate at the Carnegie Endowment's Nuclear Policy Program. In countries worldwide that have nuclear power plants or plan to build them, "There is definitely going to be a reassessment."
FULL COVERAGE: Photos, audio, video and more on Japan
GRAPHIC: Nuclear emergencies grip Japan
Already, the threat of partial meltdowns of uranium fuel rods in three Japanese reactors have forced engineers to try new, unproven tactics to prevent a runaway atomic reaction that could bring horrific environmental, economic and public health consequences. As a result, regulators in the USA and abroad have acknowledged that their safety protocols and emergency response plans will have to be revisited based on what is learned from the event.
In the United States, where 104 nuclear power reactors provide about 20% of the nation's electricity, the Japan disaster threatens to undermine a tenuous coalition of industry and environmental groups that support President Obama's push to make nuclear power a significant piece of the nation's long-term push toward energy independence. It also could change the way the government reviews and renews permits for existing plants.
One early test will be whether federal officials approve plans by Southern Co. to build a $14 billion nuclear plant in Georgia. That reactor would be the first constructed in the United States since the partial meltdown at the Three Mile Island plant in Pennsylvania in 1979.
Southern CEO Tom Fanning said Monday that his company does not expect any delays in the project, which would rely on $8 billion in federal loan guarantees backed by the Obama administration.
Officials at the Nuclear Regulatory Commission, which licenses and oversees the operation of nuclear power plants, have said the commission will review its regulatory posture based on the events in Japan. They have been circumspect, however, about whether or how its rules or approach may change.
"As we get more information from Japan, as this immediate crisis ultimately comes to an end, we will look at whatever information we can gain from this event and see if there are changes we need to make to our system," NRC Chairman Gregory Jaczko said at a White House briefing Monday.
A new scenario
The double whammy of an earthquake of enormous force followed by a massive tsunami has created emergencies at as many as nine reactors situated across three power plant complexes in Japan.
Though all the reactors shut down, the loss of power at some sites incapacitated cooling systems that pump water needed to keep the reactors' radioactive uranium fuel rods from superheating and melting. Officials pumped seawater into some of the reactors to cool them, accepting that the move will leave them forever inoperable.
If such efforts don't keep the reactors under control, the most feared outcome is that the molten fuel rods could burn through steel and concrete containment structures, escaping into the environment. The resulting release of high levels of radiation could pose health risks across a large swath of territory for many years. At the same time, officials are concerned that the quake and tsunami may have damaged on-site storage facilities holding "spent" reactor fuel rods, which can catch fire and spread high levels of radiation if exposed to air for an extended period.
While that scenario is seen by the Japanese government and many independent experts as highly unlikely, the prospect of a reactor meltdown in conjunction with a spent fuel fire would result in a catastrophe beyond the scope of Three Mile Island or even Chernobyl, the 1986 meltdown of a Ukrainian reactor that was the worst nuclear power accident in history.
"I do not believe this scenario has ever been written," said Arjun Makhijani, president of the Institute for Energy and Environmental Research. Makhijani, an engineer, specializes in nuclear fusion and has written extensively on nuclear power.
Scenarios that are considered highly improbable, such as those considered to have less than a one-in-a-million chance of occurring, typically are not considered by the NRC when reviewing nuclear plants' emergency plans, regardless of potential consequences, Makhijani said.
But in light of the events in Japan, he said, "We've got to revisit this idea of 'highly unlikely' and how we deal with it."
Nuclear power advocates note that existing safety requirements have a strong track record and dispute the notion that the disaster in Japan should automatically prompt tougher regulations.
"Thus far, from what we know, (the Japanese) have done what they need to do" to control the reactors and stave off disaster, said Steve Kerekes of the Nuclear Energy Institute, which does research in support of nuclear power. "We can anticipate that there will be lessons learned," he adds, but "whether that appropriately should manifest itself in industry practices vs. regulatory standards, it's too soon to know."
U.S. reactors have run for 3,500 combined reactor years without causing public harm, Kerekes said. That history demonstrates that the nation's nuclear power plants are safe and should be part of any long-term strategy to lessen the country's dependence on foreign oil, he said.
Yet even U.S. plants that were designed to withstand major earthquakes have not been tested in an event as severe as the one in Japan.
In 2003, the Diablo Canyon Nuclear Power Plant in Avila Beach, Calif., withstood the magnitude 6.5 San Simeon earthquake, which was centered about 31 miles from the plant.
Throughout the quake, both reactors maintained full power. But the facility is designed only to withstand ground movement generated from quakes with a magnitude of 7.5 on the Richter scale — well short of the magnitude 9.0 quake that hit Japan.
Going forward
With the outcome of the Japanese reactors still unfolding, moves to reassess the viability of nuclear power are beginning.
In Germany, for example, the government announced a three-month suspension of a decision to extend the life of nuclear power plants. That means two older ones will be taken off the grid, pending safety probes. German energy agency Dena is recommending that nuclear power be phased out and reactors in the country that are similar to those crippled in Japan be switched off, the German newspaper Handelsblatt reported.
In the United States, the NRC is weighing 12 applications to add 20 reactors in the next 15 to 20 years, according to the Nuclear Energy Institute. An additional six reactors have been put on hold in some cases as sponsors struggled financially with the effects of the recession and a drop in natural gas prices that made nuclear power less competitive.
One of the chief hurdles facing companies seeking to build power plants is paying for them. Many investors have been unwilling to shoulder the financial uncertainty associated with getting such projects approved — a costly process that can take years. And once a plant is approved, there are more monetary risks if a plant runs into safety problems.
President Obama is pushing Congress to supply $54 billion in loan guarantees to the nuclear industry, a big increase over previous levels. That would likely help fund 10 or so reactors, including the plant scheduled for Georgia, said Mark Cooper, senior fellow at the Vermont Law School's Institute for Energy and the Environment.
However, in light of events in Japan, many independent experts say political support for the initiative is sure to diminish.
"This is yet another example of how a multibillion-dollar investment can turn into a multibillion-dollar liability within minutes," Cooper said. "The only way that new reactors will be built in the United States is if the economic risk is put upon the taxpayer through federal loan guarantees and/or upon ratepayers through advanced cost recovery."
The prospects for the loan guarantee program are now "very dim," said Robert Alvarez, a scholar at the Institute for Policy Studies and former senior adviser at the Energy Department.
Contributing: Mimi Hall, Dan Vergano, Associated Press, Bloomberg News
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