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Transfer sites for 610 tons of spent nuclear fuel undecided; decommissioning plans may be affected

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Spent nuclear fuel is stored in a pool at the La Hague reprocessing facility in northwestern France in October. It is one of the most dangerous sites in the world, with its 10,000 tons of spent fuel. We were afraid of the Fukushima Daiichi fuel pool 4  but it was nothing: The whole fuel of the Hague corresponds to radiotoxicity 360 times greater than Chernobyl.

 

About 610 tons of spent nuclear fuel stored at seven of the 17 reactors in Japan that are set to be decommissioned have no fixed transfer destination, it was learned Sunday, threatening to hold up the decommissioning process.

If it remains undecided where to transfer the spent nuclear fuel, work to dismantle reactor buildings and other structures may not be carried out as planned.

The tally excludes the six reactors at Tokyo Electric Power Co. Holdings Inc.’s Fukushima No. 1 plant, which was heavily damaged by the March 2011 earthquake and tsunami.

The seven reactors are the Japan Atomic Energy Agency’s Fugen advanced converter reactor, the agency’s Monju prototype fast-breeder reactor, Japan Atomic Power Co.’s reactor 1 at its Tsuruga plant, reactors 1 and 2 of Kansai Electric Power Co.’s Mihama plant, reactor 1 of Chugoku Electric Power Co.’s Shimane plant and reactor 1 of Kyushu Electric Power Co.’s Genkai plant, according to the companies and the agency.

The Fugen reactor has 70 tons of spent mixed-oxide, or MOX, fuel, a blend of uranium and plutonium recycled from spent nuclear fuel.

The agency has abandoned its plans to move the MOX fuel out of the reactor site in the current fiscal year to March 2018. It has considered consigning the reprocessing of the fuel overseas but a contract has not been signed yet.

The agency’s schedule to finish the decommissioning work by fiscal 2033 has remained unchanged, but an official admitted that the timetable will be affected if a decision on where to transfer the spent fuel is not made.

As for the trouble-prone Monju reactor, the agency has yet to submit a decommissioning program to authorities. How to deal with 22 tons of spent MOX fuel at the reactor is a major issue.

The Mihama No. 1 reactor has 75.7 tons of spent conventional nuclear fuel and 1.3 tons of spent MOX fuel, while the No. 2 reactor has 202 tons of spent nuclear fuel. Kansai Electric plans to take them out of Fukui Prefecture, which hosts the power plant, by fiscal 2035, but the transfer location has not yet been selected.

At the Tsuruga plant’s reactor 1, Japan Atomic Power plans to transfer 31.1 tons of the reactor’s 50-ton spent nuclear fuel to the fuel pool of reactor 2, with the rest to be transported by fiscal 2026 to a Japan Nuclear Fuel reprocessing plant under construction in the village of Rokkasho in Aomori Prefecture.

After being postponed more than 20 times, the completion of the reprocessing plant is currently slated for the first half of fiscal 2018 and the blueprint is undergoing screenings by the Nuclear Regulation Authority, a nuclear watchdog.

As nuclear fuel cannot be brought into the reprocessing plant until it starts operations after receiving all necessary regulatory approval, it is uncertain whether the Tsuruga reactor fuel can be transferred as planned.

Chugoku Electric aims to transfer 122.7 tons of spent nuclear fuel at its Shimane plant’s reactor 1 to the Rokkasho reprocessing plant by fiscal 2029.

Kyushu Electric hopes to take 97.2 tons of spent nuclear fuel at the Genkai reactor 1 out of its fuel pool by fiscal 2029, but the destination has not been fixed.

At three other nuclear plants with reactors set to be decommissioned, spent nuclear fuel is mostly planned to be moved out of the current pools to other pools within the same plant.

In the case of Tepco’s disaster-stricken Fukushima No. 1 plant, the site of the 2011 triple meltdown accident, where the 2,130 tons of spent nuclear fuel will be transferred to has yet to be decided.

Still, the decommissioning work for the six reactors there will not be affected in any significant way for the time being, as more urgent tasks, such as a survey of melted fuel, have been given higher priority, officials said.

http://www.japantimes.co.jp/news/2017/04/30/national/transfer-sites-610-tons-spent-nuclear-fuel-undecided-decommissioning-plans-may-affected/#.WQa0fZxJfbI.facebook

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May 1, 2017 Posted by | Japan | , , | Leave a comment

NRA pushing dry cask storage, not pools, for spent nuclear fuel

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Japan’s nuclear watchdog will ease quake-related and other regulations on storing spent fuel to push the use of dry casks and reduce the dangers stemming from power failures at nuclear power plants.

The Nuclear Regulation Authority decided on Jan. 25 that utilities should place spent nuclear fuel in the special air cooling containers instead of the common practice of submerging the fuel rods in pools of water.

Fuel stored in pools is cooled by circulating water with pumps, but the system can shut down if earthquakes and other disasters cut off the power supply. The water could then evaporate, leaving the spent fuel and radioactive substances exposed to air.

Electric power companies have shown a positive attitude toward the dry storage system because it would enable them to keep more spent fuel when the pools are filled close to capacity.

However, municipalities that host nuclear power plants have expressed strong concerns that the system will let utilities keep spent nuclear fuel at plant sites for prolonged periods.

NRA Chairman Shunichi Tanaka stressed the need for safety.

It (dry cask storage) is much safer than storing fuel in pools,” he said.

The Great East Japan Earthquake and tsunami cut off power to Tokyo Electric Power Co.’s Fukushima No. 1 nuclear plant in March 2011. Three reactors melted down, and the cooling system would not work for more than 1,000 spent fuel assemblies in the pool in the No. 4 reactor building.

Fears arose that all water in the pool could evaporate. But emergency measures, including the pumping in of water, were taken to keep the fuel submerged.

Under the dry storage system, the fuel is sufficiently cooled in pools and placed in dedicated airtight cases. The special casks are then stored inside air-permeable facilities.

The NRA plans to promote use of casks that are currently used to transport spent nuclear fuel.

The containers have passed durability tests and can withstand falls from a height of 9 meters and high-temperature fires.

Dry storage containers are widely used in the United States and Europe.

But the use of dry casks has not spread in Japan because of the high hurdles that must be cleared. One requirement is that those containers must be stored in building that can withstand the strongest earthquake predicted in the area.

As a result, dry storage containers are used at only a few nuclear facilities in the country, such as Japan Atomic Power Co.’s Tokai No. 2 nuclear power plant in Ibaraki Prefecture.

According to the Federation of Electric Power Companies of Japan, a total of 15,000 tons of spent fuel is stored at 17 nuclear plants across Japan.

Seventy percent of their fuel pools and other storage facilities have been filled with spent fuel.

http://www.asahi.com/ajw/articles/AJ201702140004.html

February 14, 2017 Posted by | Japan | , , | Leave a comment