Reactor in Shimane Plant Restarts

Chugoku Electric Power (CEP) restarted operation of reactor #2 in Shimane Nuclear Power Plant for the first time in these 13 years on December 7^th. The power plant is located in the City of Matsue, which is the capital of Shimane prefecture, characterizing it as the only nuclear power plant in Japan in prefectural capital. The greatest concern about the plant is how the residents around it can evacuate in an emergency with nuclear accident.

The restart of Shimane Nuclear Power Plant marked the fourteenth resumption of nuclear reactor after the severe accident in Fukushima Daiichi Nuclear Power Plant in 2011. CEP extracted the control rod of reactor #2, which controls fission of nuclear fuels, in the afternoon of Saturday and reached the critical point of nuclear reaction a few hours later. Following Tohoku Electric Power Company’s reactor #2 of Onagawa Nuclear Power Plant in November, it is the second example for a boiled water reactor, the same type of reactor as Fukushima’s, to resume operation.

 

CEP plans to start sending electricity from the reactor in late December and the operation is expected to be on commercial base in early January, 2025. With expectation of lower cost for electric generation by replacing thermal generation to nuclear power, CEP is estimated to be improving the balance of its business by annual 40 million yen. It has a plan to raise its share of nuclear power generation to 15 percent in 2025.

 

Located on the coastline of Matsue city, it is likely that a tsunami will hit the plant when a great earthquake occurs in the Japan Sea. CEP constructed a fence to block tsunami with 15 meters high. It also introduced new device for reducing concentration of hydrogen leaked from a tsunami-hit reactor. Total cost for those safety measures amounted to 900 million yen. It took seven years and nine months for the reactor #2 of Shimane to pass examination of Nuclear Regulation Authority, the longest record in Japan.

 

If an accident happens in Shimane plant, the prefectural government is going to conduct evacuation of the residents around the plant. Its office is located at 8.5 kilometers southeast of the plant. In case the officers have to evacuate from the office, the government will set alternative office in Izumo City, at 28.3 kilometers southwest. It is not clear whether the distance of alternative office from the plant is far enough to work in the time of emergency.

 

450 thousand people are living within 30 kilometers from the plant, which is the third largest number around nuclear power plants in Japan. Shimane is one of the highest prefectures in the ratio of aged people, who may have difficulty in evacuation from nuclear accident. Some people are supposed to stay home in nuclear emergency, which does not guarantee protection from exposure to radiation.

 

According to a report of Tokyo Shimbun, six out of ten workers in Shimane Plant do not have any experience of operating nuclear power plant, hired after the plant stopped its operation thirteen years ago. They have been trained by retired workers or sent to other nuclear power plants to learn about actual nuclear power generation. As same as other power companies in Japan, CEP restarted nuclear reactor for business efficiency leaving concerns on safety behind.