The nuclear accident at Japan's troubled Fukushima Daiichi reactor complex appears to be heading from very bad to critical in the wake of the third explosion in four days, a fire in one of the plant's spent fuel ponds, and radiation readings spiking to deadly levels within the plant.
Authorities in Tokyo, 140 miles southwest of the plant, observed rising radiation levels yesterday, and anecdotal reports of residents leaving Tokyo are mounting. Meanwhile, iodine pills to ward off nuclear poisoning are selling out in some cities on the West Coast of the United States and Canada, despite assurances from nuclear safety authorities that the risk of harmful exposures in North America is minimal.
Whatever the immediate dangers to health, one clear victim is the growing confidence in nuclear energy internationally. German Chancellor Angela Merkel's announcement today was the most decisive turnabout in response to the crisis—she suspended her government's decision just last year to extend the operating life of Germany's nuclear power plants. She also ordered the immediate shutdown of seven plants built before 1980; officials say the plants will remain closed for safety evaluations through at least June.
Similarly doomed could be Italian utility Enel's plans to revive nuclear energy. Enel and France's Electricité de France have proposed the construction of four reactors that could provide a quarter of Italy's electricity, but they must first win a referendum that would overturn Italy's post-Chernobyl nuclear moratorium. The vote is set for this spring.
In an interview with Bloomberg News, the Indian Nuclear Power Corporation's chairman acknowledged that Japan's crisis could be "a big dampener" for his country's plans to invest in nuclear generation by 2030. China, however, was holding firm on its nuclear ambitions. The Chinese government issued a statement Monday affirming its massive shift toward nuclear power—with over a dozen reactors in construction.
The unfolding tragedy's impact on a nascent revival of reactor construction in the United States is too early to call, say experts. "It will be at least the end of the week before we will know enough about the progression of these accidents to assess policy outcomes," says Per Peterson, a professor of nuclear engineering at the University of California, Berkeley. "Much will depend upon whether any radiation deaths or significant land contamination result."
So far, the Obama administration is standing by hopes for a nuclear renaissance. Daniel Poneman, the U.S. deputy secretary of energy, said at a White House news conference Monday that nuclear has a key role in the U.S. power mix: "We have 104 operating reactors—that's 20 percent of the electricity of this country; 70 percent of the carbon-free electricity in this country comes from nuclear power. We view nuclear energy as a very important component to the overall portfolio we're trying to build for a clean energy future."
However, some in Congress are pushing for a rethink. Connecticut Sen. Joe Lieberman, chair of the Homeland Security and Governmental Affairs Committee and a longtime nuclear supporter, told CBS News this weekend that the U.S. should "quickly put the brakes" on reactor construction until the Japanese incidents are analyzed.
The U.S. Nuclear Regulatory Commission (NRC) is expected to vote this year on the first of two construction permits; the most advanced is Southern Company's proposal to build two new reactors at its Vogtle, Georgia, nuclear power plant. Southern has conditional approval for an $8.3-billion federal loan guarantee to backstop its financing and has broken ground at the site.
Meanwhile, Rep. Edward Markey (D-Massachusetts) has been critical of the NRC's decision-making on the Westinghouse AP1000—the reactor design for half of the 28 reactors proposed in the U.S., including Southern's. Markey sent a letter to the NRC last week criticizing its plan to approve the AP1000 this spring or summer despite a dissenting opinion from one of its senior engineers, who has raised doubts about the earthquake hardiness of the AP1000's concrete-steel hybrid containment building.
The earthquake concerns, ironically, undermine confidence in the passive safety system designed to make the AP1000 less vulnerable to the power blackout that sparked the Japanese crisis. The AP1000 holds a pool of water above the reactor, ready to flood it via gravity. But Markey's letter suggests that if the AP1000's containment building is compromised by an earthquake, the passive cooling system could fail.
Southern Company released a statement yesterday saying that its leadership "continues to monitor the recent events in Japan, and remains committed to completing the new Vogtle units on schedule and on budget." The statement argues that the site's seismic risk is "much lower" than Japan's, as is the risk of a tsunami 130 miles from the Atlantic coast and 220 feet above sea level.
The French nuclear engineering firm Areva also defended its EPR design, which is also pending NRC approval. While the EPR relies on active pumping to maintain reactor cooling, an Areva spokesman told Technology Review yesterday that it has extra backup generators for added redundancy. And the diesel tanks to fuel the EPR's generators would be protected by bunkers, unlike those that were washed away by Friday's tsunami in Japan.
David Lochbaum, a nuclear engineer and director for nuclear safety at the Union of Concerned Scientists, is critical of the NRC's policing of safety at existing plants in the U.S. He wants the NRC to take a second look at critical vulnerabilities to power blackouts, including outdated fire-suppression equipment and battery-power backups that, at most U.S. plants, provide for only four hours of reactor cooling—half the capacity of batteries at Japanese plants. "We're light compared to what Japan had, and Japan came up short," says Lochbaum.
Just as serious is the U.S. nuclear operators' heavy reliance on cooling ponds rather than more expensive but safer dry-cask storage of their spent fuel. Lochbaum notes that the spent fuel ponds for 23 U.S. reactors are in the attic of their concrete reactor buildings—structures that were blown away by the first two hydrogen explosions at Fukushima.
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