Assessment of interannual and intra-annual atmospheric dispersion variability parameters in the Belorussian NPP siting area

Abstract

Identification of atmospheric boundary layer (ABL) radionuclide dispersion conditions, which are characterized by ABL dispersion parameters, plays an important role in evaluating the radiation safety of nuclear power plants (NPPs) and establishing engineering protection thereof. Therefore, the ABL status monitoring observations are launched at the stage of in-situ NPP construction. When analyzing and predicting radiation situation in the NPP vicinity areas, it is of great importance to determine the parameters of atmospheric dispersion variability with time. The ABL status monitoring at the Belorussian NPP site has been carried out since September 2014 by means of acoustic and radio-acoustic sounding of the ABL. The present study is aimed at assessing interannual and intra-annual variability of atmospheric dispersion parameters in the Belorussian NPP siting area on the basis of the monitoring data. The relative interannual stability of the main average annual atmospheric dispersion characteristics (vertical temperature gradient, wind speed and direction) over the observation period has been revealed. At the same time, the average seasonal values of the dispersion parameters are characterized by significant fluctuations thereof during the annual course. The prospects of the ABL status monitoring for other potentially hazardous industrial facilities, such as thermal power plants and chemical plants, are also noted.