Risk assessment of atmospheric and liquid discharges of radionuclides on humans, marine biota and terrestrial wildlife

摘要

Egypt is currently considering building a nuclear power plant (NPP). Consequently, an environmental impact assessment is required for potential releases to the environment. The aim of this work is to implement an environmental impact assessment for a nuclear power plant to assess radiation doses to man and the wildlife, to aid the decision-making related to the environment effects of that facility. This study focused on atmospheric dispersion modeling code cap88-Pc, ERICA Tool version 1.2 and R&D128 approach for predicting the activity concentrations of released radionuclides and the corresponding dose rates to human, as well as terrestrial and marine wildlife at different distances from the reactor at normal operation. The results of total dose rate to marine wildlife, recommended that the release point to be beyond 1600 m offshore for such organisms to be protected and the summing risk quotient to be well below unity. The risk quotients for terrestrial organisms from deposited radionuclides on the ground and the emitted noble gases were well below unity. The total effective dose rate to man from air emissions and from consumption of contaminated marine species (fish and crustaceans) from liquid discharges combined was 5.19E-3 mSv y(-1)corresponding to 2.6E-7 cancer risk factor, which is acceptably low risk. The radionuclide Co-60 was one of the major contributors of dose rate to marine organisms (beside Co-58 and Mn-54) and of total effective dose for human together with Ag-110m and C-14. The current study considered to provide the baseline information for further implementation of regulatory policies when site specific data is available.