The Osaka District Court has filed a petition for a provisional injunction demanding that a citizens' group stop the operation of Unit 3 of the Mihama Nuclear Power Station in Fukui Prefecture, the only nuclear power plant in Japan that has been in operation for over 40 years. 20 days indicates judgment.
In principle, the operation of nuclear power plants is limited to 40 years after the accident at the Fukushima Daiichi Nuclear Power Plant, but Kansai Electric Power's Mihama Nuclear Power Station Unit 3, which started operation 46 years ago in 1976, has a maximum of 60 years of operation according to the government's review. As the first case where an extension is possible, it restarted in June last year.
In response, a group of citizens opposed to the nuclear power plant filed a petition with the Osaka District Court for a provisional injunction to stop the operation, arguing that there is a risk of accidents due to the deterioration of the facilities over time.
In the trial so far, the citizens' group has argued that ``the operation of aging nuclear power plants dramatically increases the risk of accidents, and there is a high risk of leading to a serious accident even if an earthquake is expected.'' argued, ``We have performed special inspections and evaluated the state of deterioration to ensure safety at the point of 60 years since the start of operation.''
There was also controversy over the sufficiency of earthquake-resistant performance against large-scale earthquakes and evacuation plans in the event of an accident.
The Osaka District Court will issue a decision on the afternoon of the 20th in response to this petition for provisional disposition.
It is the first time that the safety of the nuclear power plant, which has been in operation for over 40 years since the nuclear accident, has been challenged by the court, and it will be interesting to see what kind of judgment will be shown.
What is Mihama Nuclear Power Plant Unit 3?
Kansai Electric Power's Mihama Nuclear Power Station Unit 3, located in Mihama Town, Fukui Prefecture, began commercial operation in 1976. Under the current system, in principle, the operating period is set at 40 years. The only nuclear power plant.
The power output is 826,000 kilowatts, equivalent to about 1.85 million households.
The reactor contains 157 nuclear fuel assemblies that bundle fuel rods, weighing 73 tons of fuel, and is equipped with 48 control rods that adjust the output.
In August 2004, during operation, a pipe in the turbine building broke and hot steam spouted out, killing five workers and injuring six others.
Before the accident, it was known that the damaged pipe had never been inspected in the 28 years since the start of operation, but Kansai Electric Power Co.'s response to the failure to take countermeasures became a problem, and it took two years to resume operation. It took half.
After that, following the accident at Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Station in 2011, it was decided that, in principle, nuclear power plants that had been in operation for over 40 years would no longer be allowed to operate. In 2016, it passed both the review of the new regulatory standards of the Nuclear Regulation Authority and the review required to extend the operating period.
After that, we completed the necessary safety measures, obtained the consent of Mihama Town and Fukui Prefecture, and restarted operations in June last year for the first time in 10 years.
Under the current system that limits the operating period, it is the only nuclear power plant in Japan that has been in operation for over 40 years.
Citizen's group "I want you to become a driving force to stop aging nuclear power plants"
Prior to the decision on the 20th, a lawyer for the citizens' group said, "The '40-year rule', which sets the operation of nuclear power plants for 40 years in principle, is based on the lessons learned from the damage caused by the nuclear accident in Fukushima, and the dangers of nuclear power plants are forgotten. I hope that the decision to impose a provisional disposition will become a major driving force in guiding public opinion in the direction of abandoning aging nuclear power plants."
Kansai Electric Power "Ensuring safety, no need to stop operation"
Before the decision on the 20th, Kansai Electric Power said, ``We will carefully explain to the court that the safety of Mihama Nuclear Power Station Unit 3 has been ensured, and ask them to understand that there is no need to stop operation. We have responded sincerely. I would like you to dismiss the petition for a provisional injunction."
Examination at the Osaka District Court: Sorting out the issues
Whether the operation of Mihama Nuclear Power Station Unit 3 should be stopped.
In June of last year, a group of citizens opposed to the nuclear power plant filed a petition for a provisional injunction just before the plant was restarted.
[Impact of aging]
The most important point of contention is whether or not safety is ensured after 40 years since the start of operation.
Citizens' groups argued, "The operation of aging nuclear power plants dramatically increases the risk of accidents. Seismic design has a high risk of leading to serious accidents not only in large earthquakes that exceed expectations, but also in earthquakes that are within expectations." did.
In response to this, Kansai Electric Power said, ``We have performed special inspections and evaluated the state of deterioration, and have been approved by the Nuclear Regulation Authority to extend operation beyond 40 years. ' claimed.
[Safety against earthquakes]
On the other hand, the central point of contention in the trial was whether or not safety against earthquakes was ensured.
Citizens' groups said, ``Even though the active fault that is the epicenter of the earthquake is very close to it, it is not taken into account in the seismic design.'' They argue that it eats up safety margins, and that it does not take into account the repeated occurrence of large earthquakes like the Kumamoto earthquake in a short period of time.
In response to this, Kansai Electric said, "The Nuclear Regulation Authority has determined that the active fault is not extremely close." "The Mihama nuclear power plant is located on hard ground, and the possibility of repeated large earthquakes in a short period of time is low."
[Evacuation plan]
Furthermore, there was a debate as to whether the evacuation plan was sufficient in the event of an accident at the nuclear power plant.
The citizens' group argued that ``the current evacuation plan cannot be said to be effective''.
In response to this, Kansai Electric Power has argued, ``It has been confirmed by the National Nuclear Disaster Prevention Council that it is concrete and rational.''