Five years has passed after TEPCO Fukushima Daiichi NPP accident. Research of environmental radioactive cesium for reconstruction

Since April 2011, after the accident at TEPCO's Fukushima Daiichi Nuclear Power Station, the authors have been working on graduation research and the like targeting at environmental radioactive cesium. A large amount of radioactive cesium released from the Fukushima Daiichi Nuclear Power Station was deposited on topsoil and became an external or internal exposure source. Radioactive cesium is being recollected for decontamination with the aim reconstruction. The challenges are to understand the current state and behavior of radioactive cesium as an exposure source, and to recover and dispose of radioactive cesium. Mainly as the member of the 3rd Laboratory of the Japan Atomic Energy Research Institute, the authors have been studying on radiocesium from the viewpoints of deposition state on soil, circulation between soil and plants, removal method from soil, and contribution to air dose rate. (A.O.)