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interview

Makoto Tanaka Director of Research Co-ordination and Promotion Office,Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA)

Makoto Tanaka

Director of Research Co-ordination and Promotion Office,
Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA)

Born in 1970 in Hokkaido, Tanaka entered what was then the Power Reactor and Nuclear Fuel Development Corp. (PNC) in April 1993. In June 2011, he began working at the Support Division of the JAEA Headquarters of Fukushima Partnership Operations. In April 2020, he became head of CLADS’ research promotion department.

Problems must be solved. Fukushima must be restored. People must be satisfied. The Japan Atomic Energy Agency (JAEA) is playing a major role in realizing each. When dealing with radioactive materials—invisible radiation—information, know-how and technology are necessary, and those are the areas in which JAEA is committed. At its research facilities in the Hama-Dori region, the world’s most advanced research is being carried out on technologies for decontamination, visualization of radiation, decommissioning, and other subjects.
Because JAEA is a national research and development agency, and the only comprehensive public nuclear research institute in Japan, it has been cooperating in the reconstruction of Fukushima since the accident—ever since March 2011.
JAEA’s facilities include the Naraha Remote Technology Development Center in Naraha Town, the Joint Research Building of the Collaborative Laboratories for Advanced Decommissioning Science (CLADS) in Tomioka Town, Miharu Town and Minami Soma City, and the Fukushima Environmental Safety Center in Miharu Town and Minami Soma City. The Environmental Safety Center works together with prefectural and national organizations, such as the National Institute for Environmental Studies. Additionally, the Okuma Analysis and Research Center is under construction in Okuma Town. JAEA has a total of 330 employees in Fukushima.
The development center in Naraha Town includes a full-size reactor mock-up, a water tank for testing robots, and a virtual reality facility, and is a place to verify the performance of equipment and facilities for decommissioning is verified, train workers, and conduct research.

The two centers in Miharu Town, meanwhile, carry out research on the effects of radioactive materials on the environment, observing and analyzing the behavior of radioactive materials spreading in residential and farming areas, forests and elsewhere, and their effects on natural environments, thereby adding to accumulated knowledge for decontamination and radiation protection.
The Okuma Analysis and Research Center, under construction, is located on the premises of the Fukushima Daiichi Nuclear Power Plants. A portion of the research now being conducted at CLADS in Tomioka Town is to be transferred there. The center will analyze radioactive materials in general, and radioactive materials and waste to be generated by dismantling the reactors at the Fukushima Daiichi NPPs.
CLADS in Tomioka Town began operation in April 2017 as the base for research on decommissioning technology. We interviewed Makoto Tanaka, Director of the facility’s Research Co-ordination and Promotion Office.

– What do you do at CLADS?

Tanaka: I primarily manage research at JAEA and CLADS in Fukushima, and coordinate with domestic and overseas organizations. I studied mechanical engineering in college. Because machinery is integral to all aspects of research toward the reconstruction of Fukushima, I’m involved in many things.
I also play the role of “interpreter” among TEPCO and its associated companies involved in decommissioning. I liaise with people and parties working on issues in the reconstruction of Fukushima, including decontamination and restoration of living environments. I also work with companies and research institutions with information or technology necessary to resolve issues, as well as JAEA research groups. I ask what is needed at work sites—items and technology—and convey that to the relevant companies, JAEA or other organizations in and outside Japan. I also share ideas with people onsite. I try to remember that JAEA prepares solutions to problems before people at the worksite find themselves in difficulty.

– I understand that you are also responsible for projects at domestic and overseas universities and research institutions—projects that are invited publicly.

Tanaka: Yes, that is right. Throughout the reconstruction of Fukushima, the government, TEPCO and JAEA have maintained a policy of integrating knowledge, expertise, and experience from both Japan and abroad. Many research activities here have no counterparts elsewhere in the world, so have attracted attention internationally. CLADS invites overseas researchers and, in turn, experiments that cannot be conducted in Japan are sometimes carried out at facilities in other countries. British-made components and parts, for example, are used in remote-control equipment and facilities for decommissioning at the Fukushima Daiichi Nuclear Power Plants.
JAEA has taken over such publicly invited projects from the Ministry of Education, Culture, Sports, Science and Technology (MEXT), and implemented one named the Nuclear Energy Science & Technology and Human Resource Development Project. Every year, many domestic and overseas research institutions apply for it, bring their various ideas, and cooperate in the research, all for the purpose of successfully decommissioning Fukushima Daiichi. Results are then made available to the world, helping the global nuclear industry improve nuclear safety and to develop further.

– What do you think are the difficulties in visualizing radiation sources, recreating accidents, and researching radioactive materials at CLADS?

Tanaka: In visualizing radiation sources, we combine existing technologies, with completely new radiation imaging technology emerging. Conventionally, shielding use to be large and heavy, but a key feature of the new imaging technology is that it is light and compact. It can be transported easily and used anywhere. In particular, decommissioning work inside the reactor buildings will increase in the future, and the use of the new technology will help make it safer.
Furthermore, it has been found that the behavior of each reactor in the Fukushima Daiichi accident was slightly different. The singular accidents at each reactor can be recreated using special devices and equipment.
Some radioactive materials have too little energy to be easily detected. In order to understand their roles, we developed a variety of measuring methods. Research here is intricately connected with decommissioning at Fukushima Daiichi. Removal of fuel debris is scheduled to start as early as the end of 2022. Until then, we will improve our research results, enabling them to be applied at work sites for the safety of workers. When substantive decommissioning gets underway, then, we will be able to further refine the research based on actual outcomes and observations.

– It’s rare for researchers to see practical applications of their efforts—in this case, tangible regional contributions—isn’t it?

Tanaka: That’s right, I think. In Fukushima, research is connected to the recovery of living environments and the decommissioning of the Fukushima Daiichi. JAEA staff members live in Fukushima and share their results with people in the regional community. There is a complex called Manabi no Mori—the Tomioka Town Art and Media Center—adjacent to CLADS. Last December 5, JAEA made a presentation there to about 150 people, mostly local. The theme was “Ten Years of Steps in Decommissioning and Environmental Recovery.” The audience enjoyed the presentation, showed a high level of interest, and seemed mostly happy, too. We plan to hold a similar event annually.

– A decade has passed since the nuclear accident. Do you think that memories of the disaster are fading with time?

Tanaka: I heard from a university teacher, whom I have known through research, that today’s students are less interested in nuclear subjects. That may be an example.
At JAEA, however, I don’t feel that at all. Our decommissioning research is unique—the most advanced in the world. Researchers feel rewarded by what they are doing. Moreover, the reconstruction of Fukushima is a national project, and many people are eager about participating in it. Given the sufficient support by the government, it is likely that further research funds will be obtained.
Many of us at JAEA, when we first heard about the accident, knew our organization would be fully utilized. My own thoughts were naturally that, making use of the capabilities of JAEA, I wanted to be of help in the restoration of Fukushima. When we think of how our work can benefit the public, we become highly motivated. I want to ask other nuclear-related parties and those who are knowledgeable in the field to work with us and cooperate with our activities in order to support reconstruction of Fukushima technologically.

cooperation