Faculty Members

Faculty of Engineering

Department of Applied Nuclear Technology

Key words
Nuclear power plant maintenance, Cause analysis of accident/fault Nuclear administration of localgovernment, Providinginformation

Master of Engineering / Professor

Mikio Iwanaga


Department of Welding Engineering, Faculty of Engineering, Osaka University
Osaka University Graduate School of Engineering, Department of Welding Engineering

Professional Background

Fukui Prefecture Nuclear Safety Measures Section Manager, Nuclear Safety Examination Section, Nuclear Safety and Safety Agency, Ministry of Economy, Trade and Industry, Wakasa Wan Energy Research Center Managing Director

Consultations, Lectures, and Collaborative Research Themes

Nuclear safety issues, Maintenance of nuclear power plant, How to provide information to residents

Main research themes and their characteristics

「Nuclear Power Administration of Local Government」

 All local governments where a nuclear power plant is located have an agreement on the safety of the environment around the power plant. Originally, the safety regulation of nuclear power plants is a matter of national jurisdiction under the law. However, when an accident occurred at the power plant, it was the local government that was required to respond to the anxiety or questions of the residents of the area. For this reason, the article of the safety agreement requires business operators to report accidents, and get prior consents of local governments. However, this agreement lacks concrete administrative actions of local governments. For this reason, regarding the restart of power plants that have passed the new regulatory standards after the Fukushima Daiichi Nuclear Power Plant accident, how to proceed the administration of local governments has become a major issue.
 In Fukui Prefecture, a committee has been set up for experts in various fields to openly discuss issues such as power plant safety and national or operator responses. Along with the operation of the safety agreement, this committee is a key to the administration in Fukui Prefecture.

「Local Government Response to the Nuclear Disaster」

 Prior to the Fukushima Daiichi Nuclear Power Plant, the environmental radiation monitoring system around the nuclear power plant had been centered around 10 km from it. In Fukui Prefecture, 18 radiation observation stations in the prefecture were set up by the prefecture and 62 stations were by business operators. Using the data from these stations (radiation and meteorological data, etc.), in 1987 the country introduced an emergency rapid radiation dispersion prediction system (SPEEDI) and started operation. However, in the Fukushima Daiichi Nuclear Power Plant accident, the results of the SPEEDI system were not utilized. The new regulatory body said that the results of its diffusion calculation were unreliable and disrupted evacuation behavior, which stopped using SPEEDI. In the future nuclear disaster, it will be decided to take measures such as indoor evacuation and evacuation based on the actual measurement value of the observation station installed within the range of 30 km from the power plant. Currently, the number of observation stations in Fukui Prefecture has increased to 159 (including those outside the 30 km radius), and these observation data are available online on the websites of prefectures and regulatory bodies.
 The peculiarity of a nuclear disaster is how the radioactivity released from the power plant spreads and how the radiation rises depend on the weather conditions at the time. Therefore, local governments have to take geographical features and the weather of its area into account, and accumulate training such as evacuation.