Zaporozhye Nuclear Power Plant (NPP) commissioned a Spent-Fuel Dry-Storage Facility (SFDSF) with a 50-year service life. The SFDSF design is based on the proven technology of the US Duke Engineering & Services Company and meets international standards, rules and regulations on nuclear and radiation safety .
The objectives of this paper are calculation of the external neutron and γ-radiation of a single container, and prediction of radiation characteristics during a storage period up to 50 years.
The calculations were made for VSC-24 special ventilated containers manufactured by Sierra Nuclear Corporation (USA) .
The analysis shows that the change in gamma energy spectrum results in a faster decrease in dose with time which is in agreement with observations in the SFDSF. The γ-radiation dose rate is mainly composed of 0.5 to 2.5 MeV quanta.