THE NEW YORK TIMES
WASHINGTON — The chairman of the U.S. Nuclear Regulatory Commission gave a far bleaker appraisal Wednesday of Japan's nuclear crisis than the Japanese government had offered.
Commission Chairman Gregory Jaczko said American officials think that the damage to at least one crippled reactor was much more serious than Tokyo had acknowledged, and he advised Americans to stay much farther away from the plant than the perimeter set by Japanese authorities.
The announcement opened a new and ominous chapter in the five-day-long effort by Japanese engineers to bring the six side-by-side reactors under control after their cooling systems were knocked out by an earthquake and a tsunami on Friday. It also suggested a serious split between Washington and its closest Asian ally at an especially delicate moment.
Jaczko's most startling assertion in congressional testimony Wednesday was that there was now little or no water in the pool storing spent nuclear fuel at the Unit 4 reactor of the Fukushima Daiichi Nuclear Power Station, leaving fuel rods stored there exposed and bleeding radiation into the atmosphere.
As a result, he said, "We believe that radiation levels are extremely high, which could possibly impact the ability to take corrective measures."
Officials of Tokyo Electric Power, the Daiichi plant's operator, and Japan's nuclear regulatory agency disputed his assessment.
"We can't get inside to check, but we've been carefully watching the building's environs, and there has not been any particular problem," Tokyo Electric spokesman Hajime Motojuku said.
Speaking this morning, Takumi Koyamada, a spokesman for Japan's nuclear regulatory agency, said that when it was checked 12 hours earlier, water remained in the spent fuel pool at Unit 4.
"We cannot confirm that there has been a loss in water," he said.
But on Wednesday night, Jaczko reiterated his earlier statement and added that commission representatives in Tokyo had confirmed that the pool was empty. He said Tokyo Electric and other officials in Japan had confirmed that and also stressed that high radiation fields were going to make it very difficult to continue having people work at the plant.
Emergency workers were forced to retreat from the plant Wednesday when radiation levels soared. They resumed work after radiation levels dropped, but much of the monitoring equipment in the plant is inoperable, complicating efforts to assess the situation.
Though radiation levels at the plant have varied tremendously, Jaczko said that the peak levels reported there "would be lethal within a fairly short period of time." He added that another spent fuel pool, at the Unit 3 reactor, might also be losing water and could soon be in the same condition.
Japanese military helicopters dumped loads of seawater onto the Unit 3 reactor this morning. A CH-47 Chinook helicopter dumped at least four loads on the reactor, though much of the water appeared to be dispersed in the air.
The plant operators also said they were close to finishing a new power line that could restore cooling systems and ease the crisis. The new power line would revive electric-powered pumps, allowing the company to control the rising temperatures and pressure. The company is also trying to repair its existing disabled power line.
Tokyo Electric Power spokesman Naoki Tsunoda said the new power line to the plant is almost finished and that officials plan to try it "as soon as possible," but he could not say exactly when.
Meanwhile, the U.S. Embassy in Tokyo, on advice from the Nuclear Regulatory Commission, told Americans to evacuate a radius of "approximately 50 miles" from the Fukushima plant.
The advice to Americans in Japan represents a graver assessment of the risk in the vicinity of Daiichi than the warnings made by Japanese officials, who have told everyone within 12 miles to evacuate and those within about 20 miles to take shelter.
"We would recommend an evacuation to a much larger radius than has currently been provided by Japan," Jaczko said.
That assessment seems bound to embarrass, if not anger, Japanese officials, suggesting they have miscalculated the danger or deliberately played down the risks.
It was not immediately clear how many people live within the zone around the plant that U.S. officials think should be evacuated. But the zone gets far closer to the city of Sendai, with its population of 1 million, which took the brunt of last week's earthquake
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