Effects of radionuclide atmosphere dispersion from a hypothetical severe accident at Fangchenggang and Ninh Thuan Nuclear Power Stations to Thailand

A severe accident in a nuclear power plant can lead to a release of radionuclides which can be transported through the atmosphere, and eventually impact other countries. Fangchenggang and Ninh Thuan Nuclear Power Plants are selected for the study, since they are located near Thailand. The authors aim to reveal the atmospheric dispersion characteristics of a release from a hypothetical severe accident at both power plants, and estimate the effects to Thailand. 2.45 PBq of cesium-137 and meteorological data in 2015 of Ninh Thuan and Fangchenggang are used as the input data for the atmospheric dispersion calculation by HotSpot. It is found that low rainfall, high wind speed and high weather stability lead to large extent of radionuclide dispersion. Meteorological conditions of Ninh Thuan match the aforementioned conditions, thus they are more favorable for the atmospheric dispersion than those of Fangchenggang. The authors fitted the curve of the radiation dose equivalent of both power plants in the direction that may affect Thailand and extrapolated to the boundary of Thailand. Effects in terms of radiation dose to the public are found negligible. (author)