Modeling of atmospheric dispersion and radiological dose consequences for a hypothetical accident in the perspective of Rooppur Nuclear Power Plant (RNPP)

Bangladesh is stepping into the commercial nuclear power era with the Rooppur Nuclear Power Plant (RNPP). The RNPP constitutes a VVER-1200 nuclear reactor. The major concerns in nuclear power plants and research reactors after a catastrophic accident are the amount of radioactive element discharged into the atmosphere and the dosage received by people. Therefore, one fundamental criterion for the safety of these facilities is the computation of the estimated dosage at reactor perimeters and adjacent areas in the event of an incident. The goal of the current research was to examine the effects of a hypothetical nuclear accident by modeling the radioactive dispersion pattern from the Rooppur Nuclear Power Plant site in Ishwardi Upazila in Pabna District. The Hotspot Health Physics codes (version 3.1.2) and PCTRAN (PC-Based Transient Analyzer) were used for the work. The meteorological data of the plant site was considered with the theories of dispersion models. The amount of radioactive material that has been emitted and the external effective doses that people within a 100-kilometer distance of the site have received are calculated. A season-wise evaluation was carried out for calculating exposure pathways, committed effective dose, and plume area for both ground deposition and total effective dose. In the rainy season, dispersion was fastest with lower concentration plume area; in the winter, dispersion was slower with higher radiation concentration. In the winter, the exclusion zone (300 m) has the highest total effective dosage (0.091 Sv).