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Crucial Cooling Systems Restored at Fukushima Plant, Company Says Crucial Cooling Systems Restored at Fukushima Plant, Company Says
(about 7 hours later)
TOKYO — Vital cooling systems at the stricken Fukushima Daiichi nuclear plant were restored by Wednesday morning, more than 24 hours after a partial power failure cut cooling water to four spent fuel pools, the company that operates the plant said. The latest problem raised new fears about the continuing vulnerability of the plant, which suffered a triple meltdown two years ago and still relies on makeshift equipment. TOKYO — The stricken Fukushima Daiichi nuclear plant this week experienced its worst power failure since the disaster there in 2011, and though the plant’s operator said all electricity was restored by early Wednesday, the problem underlined its continuing vulnerability.
Although the company said the latest issue was resolved long before it became a safety risk, the temporary breakdown appeared to expose a weakness in the plant’s cooling systems. The systems were hastily built by engineers during frantic attempts to regain control of overheating reactors soon after a devastating earthquake and tsunami started the crisis at the plant. This week’s partial blackout, which started Monday, halted crucial cooling systems for as long as about 30 hours at four pools where used fuel rods are stored. The company that operates Fukushima Daiichi, the Tokyo Electric Power Company, said the plant had not been in danger because the fuel rods were never close to overheating, a state that could have led to a new, catastrophic release of radioactive materials.
The plant operator, the Tokyo Electric Power Company, or Tepco, said a faulty switchboard appeared to be to blame in the power failure on Monday. While Tepco has backup generators at the site, it appeared to have been unprepared for a switchboard failure. The company said that temperatures in the fuel pools would have remained at safe levels for at least four days.
“Fukushima Daiichi still runs on makeshift equipment, and we are trying to switch to something more permanent and dependable,” a Tepco spokesman, Masayuki Ono, told reporters Tuesday as the company worked to restore the cooling systems. But the cutoff of the vital systems appeared to support fears by some experts and critics that the plant remains dangerous in part because some vital safety systems were makeshift fixes devised at the height of the nuclear crisis.
The latest troubles also underscore the continuing worries about the safety of the plant, where a complex cleanup of three damaged reactors is expected to take decades. In particular, experts have warned that the makeshift cooling systems could be knocked out by another large earthquake. Tokyo Electric, also known as Tepco, acknowledged the concern. “Fukushima Daiichi still runs on makeshift equipment, and we are trying to switch to something more permanent and dependable,” a Tepco spokesman, Masayuki Ono, told reporters Tuesday as the company worked to restore the cooling systems.
Much of the concern has focused on the fuel pools, which contain far more radioactive material than the reactors and were built with less shielding, raising the specter of another large release of radioactive materials. The latest problems at the plant come as the government and the nuclear industry have been trying to convince jittery citizens that the country still needs its many nuclear plants. All of Japan’s plants were shuttered after the 2011 disaster as the government worked on stricter safety regulations. Two reactors were later restarted.
The four pools affected by the blackout on Monday contain more than 8,800 highly radioactive fuel rods, Tepco said. That would be enough to release far more radioactive material than the original accident in March 2011, which forced the evacuation of some 160,000 residents in northeastern Japan. Many of those evacuees still live in temporary shelters and may never be able to return home. Prime Minister Shinzo Abe recently said that the plants would begin coming on line as they were deemed safe and began nudging Japan back to its reliance on nuclear power, which he said was a must for any economic recovery.
With the company as the only source of information, it was impossible to independently assess the conditions at the plant, which sits in a contaminated zone that is closed to the public. The disaster two years ago also started with a blackout, brought on by a devastating earthquake and tsunami, which crippled the cooling systems for both the reactors and the spent fuel pools. Over the next several days, three reactors had triple meltdowns, leading to a wide release of radioactive materials that made the nuclear crisis the world’s second worst.
On Tuesday, the company was criticized for waiting three hours before revealing the power failure to the public. This week’s blackout did not affect the cooling systems for the three reactors, according to Tepco. Still, much of the continuing concern about the plant has focused on the fuel pools, which contain far more radioactive material than the reactors and were built with less shielding.
“These things are better if done quickly,” said the trade minister, Toshimitsu Motegi, whose ministry promotes the nuclear industry. The four pools affected by the latest blackout contain more than 8,800 highly radioactive fuel rods, Tepco said, enough to cause a release much larger than the original accident, which forced the evacuation of some 160,000 residents in northeastern Japan. However, experts say that as the rods have aged with time, they are producing less heat, reducing the prospect of a catastrophic fire or melting.With the company as the only source of information, it was impossible this week to independently assess the conditions at the plant, which sits in a contaminated zone that is closed to the public. On Tuesday, the company was criticized for waiting three hours before revealing the power failure to the public.
Tepco said the temporary blackout also briefly cut off electricity to the command center at the plant, though power was quickly restored. Tepco said a faulty switchboard might have been to blame in the latest power failure. Though the company has backup generators at the site, it appeared to have been unprepared for a switchboard failure.
The company also said Tuesday that the loss of cooling water was manageable because temperatures in the fuel pools would have remained at safe levels for at least four days, and the plant also has backup systems. Experts have been especially worried about the plant’s makeshift cooling systems, which could be knocked out by another large earthquake. Tepco said the temporary blackout also briefly cut off electricity to the command center at the plant.

Matthew L. Wald contributed reporting from Washington.