A simplified model to evaluate the radiological impact of an accident with a nuclear reactor submerged at the sea

¹ Laboratório de Radioecologia e Mudanças Globais (LARAMG)
² Instituto de Radioproteção e Dosimetria (IRD),Comissão Nacional de Energia Nuclear (CNEN), Av. Salvador Allende s/n°, Recreio dos Bandeirantes, RJ 22780-160, Rio de Janeiro, Brazil
³ Instituto de Matemática e Estatística (IME), Universidade do Estado do Rio de Janeiro (UERJ), Rua São Francisco Xavier, 524. Maracanã, RJ 20550-013, Rio de Janeiro, Brazil

Abstract

There are various scenarios dealing with releases of radionuclides in a water body, for example, accidents in nuclear power plants located in coastal areas, on margins of rivers or lakes. Meager attention has been given, however, to potential accidents with nuclear reactors submerged at sea. The latter type of accidents may occur with partial or total loss of the nuclear reactor core to the adjacent waters. In addition to initial instantaneous releases, one may estimate delayed sources based on rates of leaching or dissolving solid materials which are part of the core. Transport equations were used to estimate concentrations of radionuclides in water. Time dependent functions of concentrations of radionuclides in the aquatic food chain reflect the absorption and elimination processes in the flora and fauna. However, to avoid the multi-parametric complexity which can be inserted in these processes, the model takes into proper consideration in a simplified way the transfer of radionuclides through trophic levels. The model avoids the need to analyze step-by-step the details of transfer factors used to determine radionuclide accumulation in fish, crustaceans, mollusks, and algae. This simplified model may help authorities in the case of an accident with a nuclear reactor submerged at sea.