Estimation of dry deposition velocities of radionuclides released by the accident at the Fukushima Dai-ichi Nuclear Power Plant

Abstract

On the basis of environmental radiation monitoring results at the Nuclear Fuel Cycle Engineering Laboratories, Japan Atomic Energy Agency, following the Fukushima Dai-ichi Nuclear Power Plant accident, the dry deposition velocities of radionuclides on the ground were estimated. As a result, the estimated dry deposition velocities for Iodine-131, Cesium-134, Cesium-136 and Cesium-137 were in the order of 1 mm/s, and were the same order of those estimated in other studies. The estimated dry deposition velocities varied according to the variations of the ratios of the particulate and gaseous forms of their radionuclides and meteorological conditions such as wind speed.