Zhegulina I. Transboundary impact of the Chernavodska and Rivne nuclear power plants on tritium contamination of the Danube and Stir rivers.

Object of study: radiational condition of the surface waters in the areas of Chernavodska and Rivne NPP. Purpose: assessment the tritium contamination of transboundary rivers Danube and Stir in the result of exploitation of objects of high environmental risk Chernavodska and Rivne NPP. Research methods: methods of system and landscape analysis, mathematical statistics, computer modeling using the program complex PC CREAM. Theoretical and practical results: refine on process of assessment of ecological risk of transboundary pollution with tritium surface water; recommended methods for the assessment of transboundary impact of the NPP on surface water bodies. Novelty: for the first time has been done theoretical justification and experimental studies of volumetric activity of tritium in the transboundary sections of the rivers Danube and Stir; constructed the model on the basis of the program complex PC CREAM for prediction of the activity of tritium for normal and emergency operation of nuclear power plants; been done and scientifically based assessment of transboundary impacts of the Chernavodska and Rivne nuclear power plant on the waterway; been done assessment of radiation burden, radiation risks to the population caused by the increase of volumetric activity of tritium in the rivers Danube and Stir, and defined levels of environmental risk; been given further development methods of assessment of transboundary impact of the NPP on contamination by tritium of surface water bodies. The results of the thesis recommended for: nuclear power plants of Ukraine, research institutions and public authorities in the field of environmental protection.