Editer l'article Suivre ce blog Administration + Créer mon blog
Le blog de fukushima-is-still-news

information about Fukushima published in English in Japanese media info publiée en anglais dans la presse japonaise

NRA approves safety mesures at Kashiwazaki-Kariwa Nos.6 and 7

October 4, 2017


NRA approves safety measures at TEPCO plant in Niigata





Japan’s nuclear watchdog on Oct. 4 approved Tokyo Electric Power Co.’s safety measures taken to restart two reactors in Niigata Prefecture, the first such approval for the company since the Fukushima nuclear disaster unfolded.


The Nuclear Regulation Authority confirmed the results of its screening on the technological aspects of the No. 6 and No. 7 reactors that TEPCO wants to bring online at its Kashiwazaki-Kariwa nuclear plant.


It was also the first time for the NRA to conclude that boiling-water reactors, the same type as those at TEPCO’s crippled Fukushima No. 1 nuclear plant, met the new safety standards adopted after the meltdowns at the plant in 2011.


The NRA plans to hear opinions from the public about its judgment for 30 days before deciding on whether to make the approval official. It will also solicit the views of the minister of economy, trade and industry.


As one condition for official approval, the NRA is requiring the industry minister to oversee the utility’s management policy concerning its initiative and responsibility for work to decommission the Fukushima No. 1 nuclear plant.


From now, the NRA will check equipment designs and security regulations, including how TEPCO will guarantee its promise that its priority is on safety, not economic benefits.


The NRA’s screening process at the Kashiwazaki-Kariwa nuclear plant went beyond checking technological aspects of TEPCO’s safety measures. Given TEPCO’s history of mistakes and blunders, NRA members also discussed whether the utility was even eligible to operate nuclear power plants.


In response to the NRA’s demands that TEPCO take full responsibility for decommissioning the Fukushima No. 1 plant, the utility in late August stressed that its stance of putting importance on safety is “a promise to the people.”


The NRA then approved TEPCO’s eligibility but attached some conditions.


In late September, however, it came to light that workers at the Fukushima No. 1 plant were erroneously setting water gauges to measure groundwater levels of wells around reactor buildings, which could cause leaks of highly contaminated water to the outside water.


Inspectors will face a formidable challenge in judging individual issues facing TEPCO based on security regulations.


However, even if TEPCO passes all of the screenings, it must win the consent of local governments to restart the reactors at the Kashiwazaki-Kariwa nuclear plant.


Niigata Governor Ryuichi Yoneyama has said that he will wait for three or four years to make decision on the restarts, until his prefectural government completes its own investigation into the cause of the 2011 nuclear disaster at the Fukushima No. 1 plant.



TEPCO reactors clear safety review for 1st time after Fukushima



TOKYO (Kyodo) -- Two reactors in Niigata Prefecture on the Sea of Japan coast run by the operator of the crippled Fukushima nuclear plant cleared government safety standards on Wednesday, becoming the first of the utility's idled units to pass tightened screening.


The Nuclear Regulation Authority endorsed at its meeting a draft document that serves as certification that Tokyo Electric Power Company Holdings Inc.'s Nos. 6 and 7 reactors at Kashiwazaki-Kariwa power station have met the new, stricter safety standards introduced after the Fukushima disaster.


The two reactors are the newest among the seven units at the Kashiwazaki-Kariwa plant. The complex is one of the world's largest nuclear power plants, with a combined output capacity of 8.2 million kilowatts.


Despite the effective approval by the nuclear regulator, the actual restart of the two reactors will likely be at least a few years away as Niigata Gov. Ryuichi Yoneyama says it will take "around three to four years" for the utility to win local consent for the resumption of operation.


Formal approval of the restart by the nuclear watchdog is expected after receiving public opinions and consulting with the economy, trade and industry minister to confirm that Tepco is fit to be an operator.


The clearance of the two units is likely to be a boost for the government of Prime Minister Shinzo Abe, which is keen to retain nuclear power generation despite Japan suffering the world's worst nuclear disaster since Chernobyl at the Fukushima Daiichi nuclear complex in March 2011, triggered by a massive earthquake and tsunami.


Tepco, facing huge compensation payments and other costs stemming from the Fukushima crisis, has been desperate to resume operation of its idled reactors so it can reduce spending on costly fossil fuel imports for non-nuclear thermal power generation.


It filed for safety assessments of the two idled reactors at Kashiwazaki-Kariwa plant in September 2013.


In addition to assessing technical requirements, the review focused on whether Tepco is qualified to once again operate a nuclear power plant as it struggles with work to scrap the Fukushima Daiichi complex, an effort expected to take until around 2051, and reduce contaminated water around the crippled plant where radiation levels remain high.


The two reactors are boiling-water reactors, the same as those that experienced meltdowns in the Fukushima crisis. No such types have previously cleared Japan's safety standards after the Fukushima disaster, partly as they are required to conduct major refurbishment to boost safety.


Under the new safety requirements, BWRs must be equipped with filtered venting systems so that radioactive substances will be reduced when gas and steam need to be released to prevent damage to containment vessels.


The venting facilities are not an immediate requirement for pressurized water reactors as PWRs are housed in containers larger than those of BWRs, giving more time until pressure rises inside the containers.


In the review, the regulator had questioned Tepco on its posture to ensure the safety of the units. The company last month agreed to a request from the regulator to include a safety pledge as part of its legally binding reactor safety program.


Safety programs drawn up for reactors need to be approved by the regulator and if it finds a grave violation, it can demand the utility halt nuclear power operations.




TEPCO's nuclear plant to clear NRA check




Japan's nuclear regulator has taken a step further in allowing Tokyo Electric Power Company, or TEPCO, to restart its Kashiwazaki-Kariwa plant in Niigata Prefecture on the Sea of Japan coast.

The nuclear plant would be the first of those held by the operator of the crippled Fukushima Daiichi plant to soon be given the regulator's green light under the requirements introduced after the 2011 accident.

The commissioners of the Nuclear Regulation Authority on Wednesday unanimously adopted its draft assessment for the plant's No.6 and 7 reactors. The plant has 7 reactors.

The assessment says safety measures for the 2 reactors set forth by TEPCO meet the requirements.

The measures include introducing new equipment and procedures for use in case of severe accidents, such as leaks of radioactive substances from the plant's damaged containment vessel.

The reactors would also be the first of Japan's boiling-water-type reactors -- the same type as those that melted down at Fukushima Daiichi -- to get approval for restarting.

The regulator plans to invite the public to express opinions for a month starting on Thursday before it gives official approval.

Meanwhile, Niigata Governor Ryuichi Yoneyama has indicated that he will not decide on whether to give necessary consent for the restart before the prefecture's investigation into the 2011 accident is complete. The probe is expected to take 3 or 4 years.

In assessing the Kashiwazaki-Kariwa's restart, the regulator took the unusual step of looking into the eligibility of TEPCO as a nuclear plant operator.

In response, the firm promised to express determination for decommissioning the Fukushima Daiichi in the safety codes for the Kashiwazaki-Kariwa plant.

The commissioners also noted that a new emergency system to cool heated cooling water by using seawater is effective. They decided to include it in their regulation so that other boiling-water-type reactor operators take a similar measure.

They say the new system is more effective than ventilation that releases gas outside to lower inner pressure of reactors.

Outside the building in Tokyo where the NRA meeting was held, about 30 activists protested the decision. They said TEPCO is not qualified to run nuclear reactors and that the Fukushima Daiichi crisis is not over.

Partager cet article
Pour être informé des derniers articles, inscrivez vous :
Commenter cet article