Ikata nuclear power plant, foreground, is located at the root of the Sadamisaki Peninsula.
The No. 3 reactor at Shikoku Electric Power Co.’s Ikata nuclear plant in Ehime Prefecture was restarted Aug. 12, becoming the fifth reactor to be brought online under the stricter safety standards introduced in the aftermath of the 2011 Fukushima nuclear disaster.
The move followed the restart of the No. 1 and No. 2 reactors at Kyushu Electric Power Co.’s Sendai nuclear plant in Kagoshima Prefecture and the No. 3 and No. 4 reactors at Kansai Electric Power Co.’s Takahama plant in Fukui Prefecture. However, the two reactors at the Takahama plant have remained offline since March after the Otsu District Court ordered the operator to shut them down.
The No. 3 unit at the Ikata plant is now the only operating reactor in Japan that burns mixed oxide, or MOX, fuel, composed of plutonium blended with uranium.
But this reactor shares many of the serious safety problems that have been pointed out for the reactors at the Sendai and Takahama plants. It is impossible for us to support the decision to resume operations of the Ikata plant reactor without resolving these problems.
What is particularly worrisome about the Ikata plant is the anticipated difficulty in securing the smooth evacuation of local residents in the event of a serious accident.
The facility is located at the root of the Sadamisaki Peninsula, a 40-kilometer-long spear of land that juts westward into the sea with a maximum width of 6 km or so.
This narrow strip of land west of the plant is home to about 5,000 people.
The only land route for the emergency evacuation of local residents is a national highway that passes near the nuclear plant into inland areas.
Under the evacuation plan crafted jointly by the local governments in the region and the central government, local residents are supposed to be evacuated mainly by ship from ports in the peninsula if the highway becomes impassable because of an accident at the plant.
But many of the communities in the peninsula are located on slopes in coastal areas. They could be cut off from the rest of the peninsula if a landslide occurs.
There are seven radiation protection facilities within the town of Ikata, but four of them are located in designated landslide-prone areas.
People aged 65 or older account for more than 40 percent of the town’s population.
The municipal government has plans in place to support the evacuation of residents of each district. But residents say there is no way to secure evacuation of the entire town if multiple disasters occur.
People living in areas located between 5 and 30 kilometers from a nuclear power plant are supposed to take shelter in their own homes or public facilities, in principle, when a serious nuclear accident takes place.
But the series of earthquakes that rocked central Kyushu around Kumamoto Prefecture in April underscored anew the devastating effects of multiple disasters. The swarm of quakes included two registering a maximum intensity of 7 on the Japanese seismic scale, which caused severe damage to buildings across wide areas of Kumamoto Prefecture.
Ehime Prefecture is likely to be shaken violently if it is struck by the predicted massive Nankai Trough earthquake.
But the prefecture is ill-prepared for such a gigantic quake, with the ratio of public facilities that are quake-proof in the prefecture being the third lowest in Japan. These public facilities are supposed to play a key role in disaster response scenarios.
Evacuation plans are designed mainly to cope with situations in the wake of a single nuclear accident.
At the very least, however, the central and local governments should give serious consideration to the possibility of a nuclear accident being triggered or accompanied by other disasters like an earthquake and a landslide, and evaluate whether the lives of local residents will be protected in such situations.
Satoshi Mitazono, the new governor of Kagoshima Prefecture who took office last month, has indicated his intention to ask Kyushu Electric Power to halt the two reactors at its Sendai plant in response to local anxiety that has been aroused by the Kumamoto earthquakes.
Shikoku Electric Power’s decision to bring the Ikata reactor back on stream despite the fresh safety concerns is deplorable.
Another sticky issue is how to dispose of spent nuclear fuel.
If the No. 2 reactor at the Ikata plant is also restarted following the No. 3 unit, the spent fuel pool will become full in six to seven years. But there is no prospect of building a new storage facility for spent fuel.
There is no practical way, either, to reprocess spent MOX fuel.
The utility, which covers the Shikoku Island, has apparently enough capacity to meet power demand during this summer too.
The company has estimated that restarting the reactor will boost its annual earnings by 25 billion yen ($247 million). But this offers no compelling case for bringing the reactor back online at this moment.
Electric utilities, the central government and local governments in areas where nuclear power plants are located should all stop seeking to restart reactors until they have first dealt with the raft of safety issues.