Dose assessment of radionuclides dispersion from Bushehr nuclear power plant stack under normal operation and accident conditions

• The individual and collective doses around the BNPP-1 site are calculated.
• Dose and risk are presented in normal operation and under LBLOCA conditions.
• The maximum individual CEDE is 5.5E-07 Sv for normal operation condition at SE sector.
• The highest individual effective dose equivalent is 1.0E-02 Sv/y for LBLOCA condition.

Assessment of individual and collective doses around the unit-1 of Bushehr nuclear power plant (BNPP-1) site during normal nuclear reactor operation and under reactor accident conditions which are essential for safety and environmental analyses is presented in this paper. Release of radioactive materials to the environment following a design basic accident (DBA) (e.g. LBLOCA) is evaluated using HOTSPOT health physics computer code. In the normal operation conditions, atmospheric dispersion of radioactive material is calculated using CAP88-PC code. These codes utilize a Gaussian dispersion air transport plume model to simulate the atmospheric dispersion of radionuclides in different atmospheric stability classes and various wind speeds and directions. To calculate the doses under normal operation using CAP88 code, the surrounding area of the BNPP-1 within a radius of 30 km is gridded into 12 concentric rings and 16 sectors and the distribution of population and data of agricultural products are calculated for each grid. The meteorological data on atmospheric stability conditions, wind speed and the frequency distribution of wind direction based on data collected near the reactor site are also analyzed and applied. The results illustrate that the maximum total effective dose equivalent (TEDE) and committed effective dose equivalent (CEDE) values for personnel and public around the BNPP-1 site are lower than the annual effective dose limits for workers and public in normal operation and under accident conditions. Also, the results of the radiological impacts of the BNPP-1 in normal and accidental radioactive materials releases are compared with the dose values given in the Final Safety Analysis Report (FSAR) of the BNPP-1.