Seismologist testifies Fukushima nuclear disaster preventable — The Mainichi

” TOKYO — A seismologist has testified during the trial of three former executives of Tokyo Electric Power Co. (TEPCO), operator of the tsunami-ravaged nuclear plant, that the nuclear crisis could have been prevented if proper countermeasures had been taken.

“If proper steps had been taken based on a long-term (tsunami) evaluation, the nuclear accident wouldn’t have occurred,” Kunihiko Shimazaki, professor emeritus at the University of Tokyo, told the Tokyo District Court on May 9.

Shimazaki, who played a leading role in working out the national government’s long-term evaluation, appeared at the 11th hearing of the three former TEPCO executives as a witness.

Prosecutors had initially not indicted the three former TEPCO executives. However, after a prosecution inquest panel consisting of members of the public deemed twice that the three deserve prosecution, court-appointed lawyers serving as prosecutors indicted the three under the Act on Committee for Inquest of Prosecution.

Court-appointed attorneys insist that former TEPCO Vice President Sakae Muto, 67, and others postponed implementing tsunami countermeasures based on the long-term evaluation, leading to the disaster.

The government’s Headquarters for Earthquake Research Promotion released its long-term evaluation in 2002 predicting that a massive tsunami could occur along the Japan Trench including the area off Fukushima.

In 2008, TEPCO estimated that a tsunami up to 15.7 meters high could hit the Fukushima No. 1 power station, but failed to reflect the prediction in its tsunami countermeasures at the power station.

The Cabinet Office’s Central Disaster Prevention Council also did not adopt the long-term evaluation in working out its disaster prevention plan.

Shimazaki, who was a member of the Headquarters for Earthquake Research Promotion’s earthquake research panel in 2002, told the court that the Cabinet Office pressured the panel shortly before the announcement of the long-term evaluation to state that the assessment is unreliable. The headquarters ended up reporting in the long-term evaluation’s introduction that there were problems with the assessment’s reliability and accuracy.

In his testimony, Shimazaki pointed out that the Central Disaster Prevention Council decision not to adopt the long-term evaluation led to inappropriate tsunami countermeasures.

With regard to factors behind the council’s refusal to accept the evaluation, Shimazaki stated that he can only think of consideration shown to those involved in the nuclear power industry and politics.

“If countermeasures had been in place based on the long-term evaluation, many lives would’ve been saved,” Shimazaki told the court.

Shimazaki served as deputy chairman of the government’s Nuclear Regulatory Authority after the Fukushima nuclear disaster.

(Japanese original by Epo Ishiyama, City News Department, and Ei Okada, Science & Environment News Department) “

published in The Mainichi

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Tepco ordered to pay evacuees of Fukushima nuclear disaster — The Asahi Shimbun

” CHIBA–A district court here on Sept. 22 ordered Tokyo Electric Power Co. to pay 376 million yen ($3.3 million) in compensation to evacuees of the Fukushima nuclear disaster but absolved the central government of responsibility.

Forty-five people in 18 households who evacuated to Chiba Prefecture following the 2011 meltdowns at the Fukushima No. 1 nuclear plant sought a total of about 2.8 billion yen from TEPCO and the government.

About 30 similar lawsuits involving 12,000 plaintiffs have been filed at district courts around Japan.

The Chiba District Court ruling was the second so far.

In March, the Maebashi District Court in Gunma Prefecture found both TEPCO and the government responsible for the nuclear disaster and ordered compensation totaling 38.55 million yen for 62 plaintiffs.

The main point of the lawsuit in the Chiba District Court was whether TEPCO and the government could have foreseen a towering tsunami hitting the Fukushima No. 1 nuclear plant and taken measures to prevent the disaster.

The plaintiffs emphasized a long-term appraisal released by the central government in 2002, which estimated a 20-percent possibility of a magnitude-8 level earthquake occurring between the coast off the Sanriku region in the Tohoku region to the coast off the Boso Peninsula of Chiba Prefecture within the next 30 years.

The plaintiffs argued that this appraisal shows it was possible to forecast a tsunami off the coast from the Fukushima No. 1 nuclear plant, and that measures could have been taken even as late as 2006 to prevent the disaster.

For the first time in a court case involving compensation related to the Fukushima disaster, a seismologist provided testimony on behalf of the plaintiffs.

Kunihiko Shimazaki, a professor emeritus at the University of Tokyo, once served as a deputy chairman of the Nuclear Regulation Authority. He was also in charge of compiling the 2002 long-term appraisal for the government.

“The height of a likely tsunami could have been known if it was calculated based on that appraisal,” Shimazaki said in court. “Even if a specific forecast could not be made, some sort of countermeasure could have been taken.”

The defendants argued that the long-term appraisal did not provide a specific basis for predicting a tsunami and only pointed to the fact that a magnitude-8 level earthquake occurring could not be ruled out. ”

by Nobuyuki Takiguchi, The Asahi Shimbun

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Former NRA boss calls for review of safety screening method — The Japan Times

” Japan needs to review its current method for screening nuclear plant safety, seismologist and former senior regulator Kunihiko Shimazaki said in a recent interview.

The current method risks underestimating the magnitude of possible earthquakes that may hit nuclear plants, Shimazaki, former acting chairman of the Nuclear Regulation Authority, said.

He said a review was needed on the method to calculate the design basis earthquake, or the maximum quake motion that can occur around a nuclear plant, which is currently part of the NRA’s screening procedures.

Shimazaki said that he confirmed the need for such a review after examining data on powerful quakes that hit Kumamoto Prefecture and other areas in Kyushu in April.

“The NRA has to be aware that the current screening procedures have shortcomings,” he said, adding it is “very dangerous to keep using the method.”

Before leaving the NRA in September 2014, Shimazaki was in charge of assessing quake and tsunami impacts as part of its nuclear safety screening process.

The current method risks underestimating design basis earthquakes when it is applied to vertical faults found mainly in western Japan, he said.

The design basis earthquakes for Kansai Electric Power Co.’s Takahama and Oi nuclear plants, both in Fukui Prefecture, and Kyushu Electric Power Co.’s Genkai nuclear plant in Saga Prefecture, should be recalculated based on a different method, he said.

The NRA should draw up a revised method by taking into account new data, including on strong tremors such as the Kumamoto quakes, Shimazaki said.

The No. 3 and No. 4 reactors at the Takahama plant have passed the NRA’s safety screening. The NRA is expected to approve Kansai Electric’s request for extending operational periods at the plant’s No. 1 and No. 2 reactors beyond 40 years, a basic lifetime for nuclear reactors in Japan. ”

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NRA’s final ruling on fault to force scrapping of Tsuruga reactor — The Japan Times

” A panel convened by the Nuclear Regulation Authority said Thursday its opinion that a fault beneath a reactor at the Tsuruga nuclear power plant is active has not been swayed by the additional data provided by its manager.

The move leaves Japan Atomic Power Co. no choice but to scrap the No. 2 reactor at the two-unit Tsuruga complex, which sits on the Sea of Japan coastline of Fukui Prefecture.

The NRA acknowledged last year that the fault is active, but Japan Atomic later submitted additional data to overturn the regulator’s judgment, which the panel rejected at its meeting on Thursday.

Taiki Ichimura, vice president of Japan Atomic Power, called for more discussions on the issue, but NRA Commissioner Kunihiko Shimazaki brushed it off, saying that its ruling was final.

“Enough scientific debates have been held,” he said.

The nuclear regulator might compile an amended version of its report as early as in October to reflect changes in details. ”

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Japan inches toward restarting a nuclear plant — CBS News

” TOKYO — A Japanese nuclear plant won preliminary approval Wednesday for meeting stringent post-Fukushima safety requirements, clearing a major hurdle toward becoming the first to restart under the tighter rules.

The Nuclear Regulation Authority accepted a 418-page report that found that design upgrades and safety improvements at Kyushu Electric Power Co.’s two reactors at the Sendai Nuclear Power Station have complied with the requirements introduced last July.

The regulators said the plant is now deemed capable of avoiding severe accidents such as the Fukushima Dai-ichi meltdowns in an equally serious situation. All of Japan’s 48 remaining reactors are offline for safety checks and repairs since the 2011 earthquake and tsunami hit Fukushima Daiichi, causing multiple meltdowns. … ”

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Ohi nuclear plant operator tightens safety — NHK World

” The operator of the Ohi nuclear power plant in central Japan has submitted to regulators a revised estimate for tremors from potential earthquakes at the plant.

Kansai Electric Power Company was aiming at an early restart of the off-line plant. But the revision concerning the possible impact of a quake would require additional reinforcement. This could take time.

The revision was demanded by the country’s Nuclear Regulation Authority in its safety screening, a precondition for the plant’s restart.

The utility on Wednesday revised the depth of the potential epicenter of a nearby quake from 4 kilometers to 3 kilometers. This means a stronger tremor would shake the plant.

NRA Commissioner Kunihiko Shimazaki approved of Kansai Electric Power’s decision, calling it a safer path.

The revision would require the operator to spend significant time strengthening the plant’s facilities. The utility will be facing a summer without nuclear power for the first time since the 2011 Fukushima Daiichi disaster as another plant also needs to clear similar hurdle.

The Ohi plant was allowed to operate for 14 months through September last year as an exceptional case to cover Osaka and surrounding areas’ demand for electricity after the Fukushima Diichi disaster.

The plant is one of the first 6 nuclear power plants to apply for the tightened safety screening last July. ”

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