Research and development in the fiscal year 2022 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 FY2022. 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, its management, and safeguards 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 of groundwater flow in Ningyo-toge and the speed-up and stabilization of large-scale computation. As for "Uranium waste engineering research", the technique for separating dissolved uranium and the development of materials used for waste containers with consideration of the retrievability are reported. Further, the followings are also reported: the summary of safeguards activity in the Ningyo-toge Environmental Engineer Center, the radon and thoron exhalation testing at building interior walls, and the biological effects of radon inhalation and X-ray irradiation. The achievements of those works have been widely presented through research papers etc.