Dry storage for Hamaoka

January 27, 2015

Chubu Electric applies with NRA to build dry storage facility at Hamaoka nuclear plant

http://mainichi.jp/english/english/newsselect/news/20150127p2a00m0na014000c.html

Chubu Electric Power Co. applied with the Nuclear Regulation Authority (NRA) on Jan. 26 for permission to build a dry storage facility for spent nuclear fuel from the No. 4 reactor at its Hamaoka nuclear power plant in Shizuoka Prefecture.

The power company wants to build a dry storage facility on the premises of the Hamaoka Nuclear Power Plant so that it won't have to store spent nuclear fuel in a fuel pool. If completed, it will be the third such facility at nuclear plants in Japan. Following the outbreak of the crisis at the Fukushima No. 1 Nuclear Power Plant, NRA Chairman Shunichi Tanaka said that dry storage facilities, which were said to be safer than spent nuclear fuel pools, were "desirable." While spent fuel pools in Japan are nearly completely full, there has been little press in the shift toward the dry storage method.

Under the dry storage method, spent nuclear fuel is stored in a steel container called "cask" after being cooled in a spent fuel pool for at least several years. Such facilities are believed to be less vulnerable to earthquakes and tsunami as they do not need electric power and spent nuclear fuel can be cooled naturally by air. Chubu Electric released the dry storage facility scheme in 2008 when it decided to decommission the No. 1 and No. 2 reactors at the Hamaoka plant. The utility plans to start operating the dry storage facility in fiscal 2018 and store 400 metric tons of spent nuclear fuel there for up to 50 years.

There are similar facilities at the Fukushima No. 1 Nuclear Power Plant and Atomic Power Co.'s Tokai No. 2 nuclear power plant in Ibaraki Prefecture with a storage capacity of about 500 tons and 250 tons, respectively. As for such facilities outside nuclear power stations, Tokyo Electric Power Co. and Atomic Power Co. are jointly building a dry storage facility with a capacity of 5,000 tons in the Aomori Prefecture city of Mutsu.

At the Fukushima nuclear power plant's No. 4 reactor where hydrogen explosions occurred in its reactor building, all of the nuclear fuel, including spent fuel, was stored in a fuel pool. The fuel could not be cooled because the facility lost power, and there was a danger of nuclear fuel melting as it was laid bare in the fuel pool that dried up temporarily. The nuclear fuel stored in a dry facility at the same nuclear plant remained intact.

Nevertheless, no new dry storage facility plan has been released so far since the Fukushima disaster. That's because local residents have deep concerns that if utilities were to build such facilities, spent nuclear fuel could be disposed of in their areas permanently. There appears to be even stiffer opposition from local residents to any plan to build such facilities outside the premises of nuclear power stations.