This article explains the technological progress in decommissioning work at the Fukushima Daiichi Nuclear Power Plant and the challenges of the people involved, centering on content from a special talk session held at the Osaka-Kansai Expo.
Decommissioning work at the Fukushima Daiichi Nuclear Power Plant is proceeding based on the government's mid-to-long-term roadmap, centered on five main tasks: 'contaminated water countermeasures,' 'disposal of ALPS-treated water,' 'fuel removal,' 'fuel debris removal,' and 'waste countermeasures.' In September 2024, trial removal of fuel debris began, entering the 'Phase 3' process defined in the roadmap. The first trial removal of fuel debris succeeded in November 2024, and the second in April 2025, with this unprecedented, technically challenging effort steadily advancing.
The working environment at the decommissioning site has dramatically improved, with work now possible without protective clothing in approximately 96% of areas. Taketsuna Watanabe from Tokyo Power Technology, who was involved in fuel debris removal work, said 'Since everything was a first, I felt great pressure, but when we succeeded, I felt great satisfaction.' Yasunaga Yokogawa from TEPCO Holdings revealed the site's dedication, saying 'The second time, we applied lessons from the first and work proceeded without trouble, and I was amazed by the high technical capability of the site.'
The decommissioning site has become a place of innovation where experts from various fields gather. Akihiro Tagawa from the Japan Atomic Energy Agency is developing technology to visualize radiation on PC and predict contamination conditions. Hong-gyu Min from Liberaware, who develops drones for confined spaces, stated 'Technology developed in the harsh environment of decommissioning is trusted anywhere,' and Naohisa Hoshikawa from Okuma Diamond Device, who develops diamond semiconductors, emphasized 'If it can operate at a decommissioning site, it can operate in space,' with plans to establish the world's first diamond semiconductor manufacturing plant in Okuma town in 2026.
Technical succession to the next generation is also advancing. Since 2016, the 'Decommissioning Creative Robot Contest' has had students from technical colleges participate in robot competitions simulating actual decommissioning work. Ayuki Tsukada from Fukushima Technical College, who participated in the 9th contest, expressed determination saying 'In the future, I want to develop robots that will be active at the Fukushima Daiichi Nuclear Power Plant decommissioning site.'
The article conveys the image of people proudly taking on the difficult challenge of decommissioning and the steady progress of efforts to turn this trial into an opportunity to create new technologies and industries.