Japan Renews Nuclear Efforts as U.S. Sounds Alarm
NORIHIKO SHIROUZU REBECCA SMITH ANDREW MORSE
Yumiko Ono reports from Tokyo on the confusion there over the differing assessments of the radiation danger from the damaged Fukushima Daiichi power plant. Plus, Japanese officials scramble to dump water on the damaged reactors to cool them down.
The Japanese government renewed efforts to tame the nuclear power plant at the center of Japan's nuclear crisis after suffering some delays Thursday, even as it waited for results of its attempt to cool pools of hot nuclear waste on the scene with seawater carried by helicopter.
The efforts came amid an apparent split with U.S. officials on the severity of the problem. The State Department said in a notice to U.S. citizens late Wednesday that "those in Japan should consider departing" and reiterated its urging that they put off travel to the country. The U.S. also instructed its troops and citizens to stay at least 50 miles away from the Fukushima Daiichi nuclear power plant in northeastern Japan—establishing a "no-go" zone far wider than the buffer recommended by the Japanese government itself.
Helicopters Drop Water on Reactors
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But U.S. and Japanese officials played down the perception that the two countries are in disagreement, saying they are talking regularly and that the U.S. continues to help Japan with its unfolding crisis.
Also Thursday, government officials as well as Tokyo Electric Power Co. warned that Tokyo could face broad power blackouts that night if electricity usage isn't cut below levels seen earlier in the day. The utility, known as Tepco, continues to wrestle with bridging a supply gap of as much as 25% following the earthquake and subsequent shutdown of two nuclear power plants in northern Japan on Friday.
Japan authorities raised the death toll Thursday to 5,457, with another 9,508 missing, though the numbers are expected to climb.
Two helicopters each made two sorties, dropping seawater on a pool containing spent fuel rods in the building housing the plant's reactor No. 3, government officials said. It's unclear how much water made it into the pool containing the rods.
Government officials said the No. 3 pool was higher priority than the No. 4 pool, which Wednesday also showed signs of potentially dangerous overheating, because they can still see water in that pool.
Nuclear physicist James Acton and WSJ's Lee Hotz discuss whether Japan can avoid nuclear disaster as workers scramble to cool the overheating spent fuel at the Fukushima Daiichi power plant.
A plan to drench the reactor facilities at the No. 3 reactor via fire truck suffered delays when authorities couldn't get seawater from the ocean into the truck's tanks. By then, radiation levels at the facility had climbed to an unsafe level. Shortly before 8 p.m. local time, however, national broadcaster NHK reported that the operation had begun.
Government officials haven't yet disclosed the results of efforts to connect outside power cables to two of the units at the stricken plant, in hopes of restarting their cooling pumps. They had hoped to have the cables available by Thursday afternoon.
U.S. officials stressed that the State Department's notice late Wednesday related to voluntary departures and fell short of what's known as an ordered departure, as it issued in Libya during the recent uprising, that requires citizens to leave.
Yukio Edano, Japan's chief government spokesman, said in a news conference that it is understandable that the U.S. would make a more "conservative decision" when trying to ensure the safety of its citizens abroad, in a country where it doesn't exert direct control. But he reiterated that the Japanese government was repeatedly checking the radiation levels in the area and felt it was taking appropriate measures for its own citizens.
U.S. and Japanese officials said there have been close communications between the two nations on all levels. In his second phone call to the Japanese prime minister since a massive earthquake and tsunami devastated the Tohoku region in northeast Japan, President Barack Obama promised Prime Minister Naoto Kan early Thursday that the U.S. will do "everything possible" to support Japan.
Earlier in the day, the top U.S. nuclear regulator, Gregory Jaczko, called radiation levels at one of the plant's units "extremely high," adding that, "for a comparable situation in the United States we would recommend an evacuation for a much larger radius than is currently being provided in Japan."
Previously the U.S. had agreed with Japanese officials that a 12-mile evacuation zone was adequate. The change came after the NRC ran computer-modeling exercises using "the best available information we have" about the damaged reactors along with accumulated knowledge about how systems inside nuclear plants perform under "severe accident conditions," a spokesman with the Nuclear Regulatory Commission said.
Japan's main stock index, which had dropped as much as 5% at one point, narrowed those losses to end 1.4% lower, as investors held out hope for the latest attempts to keep nuclear material at Fukushima Daiichi under control.
Japan's nuclear crisis deepened as a fresh fire broke out in a quake-ravaged nuclear complex and expats fled Tokyo over warnings of radiation leaks. WSJ's Mariko Sanchanta and Yumiko Ono discuss.
As part of the government effort to take on a larger role in the crisis management, on Wednesday plant operator Tepco said 20 government officials had moved into the company's offices as part of a joint crisis headquarters.
The government's use of helicopters to dump water on the site was ordered by Economics Minister Banri Kaieda. "The minister considered the situation to be dangerous and judged there was an imminent necessity to issue the order," said a spokesman for the Nuclear and Industrial Safety Agency, which is part of Mr. Kaieda's purview. "After learning that Tepco was not injecting cooling water, he judged it to be very dangerous."
Two helicopters made two trips each, scooping up tons of seawater in a massive bucket and then trying to dump it into a pool used to store waste-fuel at reactor No. 3. An earlier explosion had blown the roof off of the building, exposing the storage pool and making the helicopter mission possible.
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Because of radiation risk, the helicopters had to maintain considerable altitude. A government official said it wasn't yet clear whether the water hit its target.
The race to build an emergency power supply for the crippled plant, combined with details from the early moments of the crisis, highlight new questions about the design and safety record of the facility, which is Japan's oldest.
Common to all nuclear plants is this fundamental design problem: Engineers try to make the equipment impervious to one threat, but that may make it vulnerable to another.
In this case, the Fukushima Daiichi nuclear complex's back-up diesel-powered generators were built below ground level. This bunker-like positioning would protect the generators from an air strike, cyclone or typhoon—but made them more vulnerable to an earthquake-driven tsunami.
When last week's giant waves struck, they immobilized the generators despite being designed to protect against water. The tsunami also apparently washed away the generators' fuel tanks, which were above ground.
"The earthquake and tsunami we had last week both exceeded our engineering assumptions by a long shot," said Tetsuo Ito, head of Kinki University's Atomic Energy Research Institute, near Osaka. "The nuclear industry around the world probably will have to review how we set those assumptions in designing a nuclear power plant."
Another area of scrutiny is the proximity of the plant's six reactors to one another. Damage to one reactor contributed to damage to another, and their proximity hindered a recovery.
This arrangement can be found at other plants, because it can make it easier to move equipment around and helps to keep a smaller work force, said Mr. Ito. But now it looks like a "bad idea," he said. "We need to strike a better balance of operational efficiency and safety."
Terry Pickens, director of nuclear regulatory policy at Xcel Energy Inc. of the U.S., said there is no cookie-cutter reactor of the vintage of the Fukushima units because utilities in those days hired their own engineering firms and architects, and customized the plants' designs. At Xcel's Monticello plant in Minnesota, diesel generators are kept as far apart as possible so that "a natural phenomenon isn't likely to take both of them out," Mr. Pickens said.
The Japanese plant lost power during Friday's earthquake. The three active reactors shut off automatically as designed, but a lack of electricity left workers unable to operate their cooling systems, leading to overheating. Tepco says the tsunami paralyzed all but one backup generator.
In a weekend briefing, Tepco Managing Director Akio Komori cited the elevation of the backup generators as one potential issue. A Tepco spokesman confirmed the remarks, adding that a full probe will have to wait while workers try to bring the reactors under control.
A spokesman for Japan's Nuclear and Industrial Safety Agency, the nation's nuclear-power regulator, said Fukushima Daiichi's emergency-generator design is "fairly prevalent" at other Japanese plants. The spokesman, Shigekatsu Ohmukai, disputed that the elevation of the generators was a problem. The agency, he said, had concluded that the plant could withstand a certain size of tsunami but "obviously the tsunami caused by Friday's earthquake exceeded our assumptions. That's the problem."
Tepco tested the Fukushima Daiichi plant to withstand an earthquake magnitude of 7.9—a level of seismic activity the power company thought wouldn't be surpassed in the area, according to company documents on its website from 2010. The quake that struck Friday, however, was about 10 times as big as that theoretical maximum.
In the U.S., where there are 23 similar reactors operated by 11 different companies, backup generators typically are housed in bunker-like buildings at ground level. They are designed with watertight fittings that are intended to keep out water from floods or hurricanes.
General Electric Co. designed three of the six reactors for Tepco at the Daiichi complex but it didn't determine the layout of every piece of equipment, a company spokesman said. Some of that was done by architects and engineers hired by Tepco. He added that the main problem was the larger-then-expected tsunami, not the generator placement.
The Daiichi plant was central to a falsified-records scandal a decade ago that led Tepco to briefly shut down all its plants and led to the departure of a number of senior executives. Nuclear experts say that led to a number of disclosures of previously unreported problems at the plant.
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