Sunday, June 19, 2011

Tepco Says Failure at Water Decontamination Won’t Delay Nuclear Shutdown

Tokyo Electric Power Co. played down concern a solution to its nuclear crisis may be delayed, one day after finding more radiation than expected must be removed from millions of gallons of water before work can proceed on a shutdown. Decontamination efforts at the Fukushima Dai-ichi plant were halted yesterday after a filter expected to remove the radioactive element cesium for several weeks exceeded capacity in just five hours. Oil and sludge in the water contained more radiation than expected,
said Junichi Matsumoto, a spokesman for the utility. “The entire cooling process has been suspended because of the shutdown of the water decontamination system,” Matsumoto said at a media briefing in Tokyo today. “We’re still looking for a solution, but this won’t delay step one of the road map, in which we try to achieve stable cooling status by mid-July.” Decontamination of about 105 million liters (28 million gallons) of water in basements and trenches at Fukushima Dai- Ichi was halted after the level of cesium in a filtering unit reached 4.7 millisieverts of radiation, Matsumoto said yesterday. The units generally need replacement at a level of 4 millisieverts, and the company had expected the unit to last about a month, he said.
‘Simple System’
“Tepco should have had a very simple water decontamination system of its own,” said Tadashi Narabayashi, a nuclear engineering professor at Hokkaido University. “Then, it’s easy to fix or replace a troubled part by themselves.” The utility, known as Tepco, on April 17 outlined plans to end within six to nine months the world’s worst nuclear crisis since Chernobyl in 1986. The first stage is to reduce radiation levels at the plant within three months and then achieve a so- called cold shutdown where reactor temperatures fall below 100 degrees Celsius (212 degrees Fahrenheit). Tepco said today it will vent pressure from the No.2 reactor building to aid cooling and keep on schedule the first phase of progress. There will be “limited impact” on the environment from this, Matsumoto said. The Fukushima plant suffered three reactor meltdowns after the March 11 earthquake and tsunami knocked out power and backup generators, crippling its cooling systems. Japan in April raised the severity rating of the crisis to 7, the highest on an international scale and the same as the Chernobyl disaster. Tepco has been criticized for its slow response to the accident and for publishing erroneous radiation data, while the government-run Nuclear and Industrial Safety Agency has been blamed for not ensuring the utility heeded warnings that a tsunami could overwhelm the plant’s defenses.
What Went Wrong
The utility is now the subject of study by Yotaro Hatamura, appointed by Prime Minister Naoto Kan last month to head a 10- member team conducting an “impartial and multifaceted” investigation into what went wrong and how to prevent a repeat. Hatamura told reporters in Tokyo last week that plant manager Masao Yoshida, said he couldn’t imagine such a huge tsunami. “From our discussions, I gathered that no one at the plant could imagine that such a tsunami would occur,” Hatamura said.
While it struggles to shut down the reactors Tepco is also preparing to compensate victims of the disaster, including 50,000 households displaced because of radiation leaks. Japan’s Cabinet on June 14 approved a disaster compensation bill to help the utility pay reparations. The nation’s largest banks and insurers, including Sumitomo Mitsui Financial Group Inc. and Dai-ichi Life Insurance Co., will provide short-term operating funds to Tokyo Electric, according to local media reports. Japan’s government is discussing plans for a fund of several hundred billion yen to finance reconstruction and support families and companies in the disaster-hit prefectures of Fukushima, Miyagi and Iwate, the Nikkei newspaper reported today. Fukushima Governor Yuhei Sato reiterated his opposition to restarting Tepco’s nuclear reactors in the prefecture, the Asahi newspaper reported today. Sato said he will respect and adhere to the denuclearization outline of a prefectural committee on reconstruction, the newspaper reported. Municipal authorities in Fukushima City have expanded radiation monitoring to 1,045 spots, from 100 observed earlier, the Yomiuri newspaper reported yesterday.
Supply ‘Gap’
Trade Minister Banri Kaieda yesterday said he may let utilities restart nuclear generators that had been shut for routine maintenance. There are negatives to suspending all nuclear power, Kaieda said at a press briefing in Tokyo, citing an expected “gap” in power supply and demand in Japan’s coming summer months. Hatamura indicated his team will probe whether an earthquake-prone country such as Japan should build its energy policy around nuclear plants. Because of the inherent dangers, it’s a mistake to treat the industry as safe, he said.

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