On March 11, 2011, a massive earthquake and the resultant tsunami struck the Tohoku area of Japan, causing serious damage to the Fukushima Daiichi Nuclear Power Plant (NPP) and the release of a significant quantity of radionuclides into the surrounding environment. This accident underlined the necessity of establishing more comprehensive scientific research for promoting safety in nuclear technology. In this situation, the Kyoto University Research Reactor Institute (KURRI) established a new research program called the “KUR Research Program for Scien­tific Basis of Nuclear Safety” in 2012.

Nuclear safety study includes not only the prevention of nuclear accidents but also the safety measures after the accident from a wider point of view ensuring the safety of residents. A long time is needed for the improvement of the situation, but the social needs for the reinforcement of nuclear safety increases rapidly. The advancement of disaster prevention technology for natural disasters such as earthquakes and tsunamis, the reinforcement of measures to counter the effects of accidents, and the reinforcement of the safety management of spent fuels and radioactive wastes are demanded, not to mention the reinforcement of nuclear reactor safety. Also required are the underlying mechanism investigation and accurate assessment for the effect of radiation on the human body and life. As with all such premises, detailed inspection and analysis of the accident are indispensable.

In the Research Program for the Scientific Basis of Nuclear Safety, an annual series of international symposia was planned along with specific research activities. The first in the series of symposia, entitled “The International Symposium on Environmental Monitoring and Dose Estimation of Residents after Accident of TEPCO’s Fukushima Daiichi Nuclear Power Stations”, was held on December 14, 2012, concerning the radiological effects of the accident on the public, and covering a wide range of monitoring and dose assessment activities after the accident. Although the proceedings of the symposium had been published, a more comprehensive and conclusive book was published with open access at the requests of many people including residents near the accident site.

Following the first one, the second annual symposium in this series was held on November 28, 2013, dealing with nuclear back-end issues and the role of nuclear transmutation technology after the accident at TEPCO’s Fukushima Daiichi NPP. The accident has called upon us to focus our attention on the large amount of spent nuclear fuels stored in NPPs as well as on the impacts of the accident. In fact, public anxiety regarding the treatment and disposal of high-level radioactive wastes which require long-term control is now growing, while the government policy on the back-end of the nuclear fuel cycle is unpredictable in the aftermath of the accident. The issues are not simply technical, they are critically important not only for dealing with the accident but also for pursuing nuclear energy production in the world.

This publication summarizes the current status of the back-end issues and of research and development on nuclear transmutation technology for radioactive waste management. It is expected to contribute to better understanding and further discussion of the issues.

On behalf of KURRI, I wish to thank all the contributors to this book as well as the reviewers. KURRI hopes that this publication will promote further progress in nuclear safety research and will contribute to the reduction of public anxiety after the accident.

Kyoto University Research Reactor Institute Hirotake Moriyama

Kyoto, Japan