Abstract
Background: The evaluation of skyshine distribution, release of airborne radioactive nuclides, and soil activation and groundwater migration were required for radiological assessment of the impact on the environment surrounding In-Flight (IF)-system facility of the RAON (Rare isotope Accelerator complex for ON-line experiment) accelerator complex.Materials and Methods: Monte Carlo simulation by MCNPX code was used for evaluation of skyshine and activation analysis for air and soil. The concentration model was applied in the estimation of the groundwater migration of radionuclides in soil.Results and Discussion: The skyshine dose rates at 1 km from the facility were evaluated as 1.62 × 10-3 μSv·hr-1. The annual releases of 3H and 14C were calculated as 9.62 × 10-5 mg and 1.19 × 10-1 mg, respectively. The concentrations of 3H and 22Na in drinking water were estimated as 1.22 × 10-1 Bq·cm-3 and 8.25 × 10-3 Bq·cm-3, respectively.Conclusion: Radiological assessment of environmental impact on the IF-facility of RAON was performed through evaluation of skyshine dose distribution, evaluation of annual emission of long-lived radionuclides in the air and estimation of soil activation and groundwater migration of radionuclides. As a result, much lower exposure than the limit value for the public, 1 mSv·yr-1, is expected during operation of the IF-facility.