Research and development in the fiscal year 2021 in Ningyo-toge Environmental Engineering Center; Topics

Ningyo-toge Environmental Engineering Center

This report outlines some main research and development activities executed by the Ningyo-toge Environmental Engineering Center in FY2021. The Center was working on the development of the nuclear fuel cycle with a focus on its front-end (i.e., uranium exploration, mining, refining, conversion, and enrichment) until 2001, and is now dismantling and removing the facilities and equipment used in the past. In addition, based on the concept of "Uranium and environmental research platform" announced in 2016, we are also working on research and development for the safe processing and disposal of uranium wastes to steadily keep the decommissioning. This research and development can be mainly divided into "Environmental research" and "Uranium waste engineering research"; the former takes advantage of the characteristics of the natural environment in Ningyo-toge, and the latter utilizes our facilities and potentials. Some works are also made on safety and its management as well as radiation effect research in terms of health physics and radiobiology. Regarding "Environmental research" and environmental conservation, this report describes researches on the characteristics and distribution of aquifer in Ningyo-toge and better geotechnical structure estimation methods. As for "Uranium waste engineering research", the decontamination using ultrasonic cleaning and the elemental analysis of uranium waste are reported. Further, the followings are also reported: the improvement of the radiation management system, the text mining approach for information extraction from safety-related documents, the intake and biological effects of radon, and the behavior of trace elements and radionuclides in the ecosystem of Ningyo-toge. The achievements of those works have been widely presented through research papers etc.