Public exposure from environmental release of radioactive material under normal operation of unit-1 Bushehr nuclear power plant

Abstract

The Unit-1 Bushehr Nuclear Power Plant (BNPP-1), constructed at the Hallileh site near Bushehr located at the coast of the Persian Gulf, Iran, is a VVER type reactor with 1000MWe power. According to standard practices, under normal operation conditions of the plant, radiological assessment of atmospheric and aquatic releases to the environment and assessment of public exposures are considered essential. In order to assess the individual and collective doses of the critical groups of population who receive the highest dose from radioactive discharges into the environment (atmosphere and aquatic) under normal operation conditions, this study was conducted. To assess the doses, the PC-CREAM 98 computer code developed by the Radiation Protection Division of the Health Protection Agency (HPA; formerly called NRPB) was applied. It uses a standard Gaussian plume dispersion model and comprises a suite of models and data for estimation of the radiological impact assessments of routine and continuous discharges from an NPP. The input data include a stack height of 100m annual radionuclides release of gaseous effluents from the stack and liquid effluents that are released from heat removal system, meteorological data from the Bushehr local meteorological station, and the data for agricultural products. To assess doses from marine discharges, consumption of sea fish, crustacean and mollusca were considered. According to calculation by PC-CREAM 98 computer code, the highest individual dose in terrestrial area for adults is 14×10−5mSv/y in ESE direction and 600m distance from stack. Also, the individual dose via discharge of liquid effluents to the Persian Gulf is 5×10−7mSv/y. Furthermore, total collective dose around BNPP-1 site within 100km radial is calculated using local data and consumption habits. The results show that the radiological impact of the BNPP-1 on the critical groups of public and the individual effective doses are in good agreement with the values given in the Final Safety Analysis Report (FSAR-2007) and the Environmental Report of the BNPP-1. Also the calculated ambient gamma dose rates match relatively well with the monitored dose rate values of the environmental monitoring stations around the reactor under normal operation conditions. It can also be concluded that the estimated effective doses are lower than the dose constraint of 0.1mSv/y associated with this plant. The results are presented and discussed.