NEAR AND FAR FIELDS OF A RADIOACTIVE WASTE DISPOSAL FACILITIES: APPROACHES TO THEIR MODELING BASED ON THE GERA SOFTWARE

The study focuses on the safety assessment of near-surface radioactive waste disposal facilities (NSDF) based on the numerical simulation of radionuclide transport in the near field via groundwater flow and mass transport processes using the GeRa software. It also evaluates the methods that may provide near and far field model coupling seeking to arrange a sound safety assessment process. The study specifically focuses on the degradation of the underlying concrete safety barrier indicated through a reduced radionuclide absorption capacity. The study provides calculations for those radionuclides that are typically found in the radioactive waste subject to disposal in deep disposal facilities. The findings evidence some fundamental difference in the activity-yield curves associated with the sorption properties, changes in the barrier properties and the half-lifes of the modelled radionuclides.

Keywords: radioactive waste, engineered safety barriers, concrete degradation, near field, far field, GeRa software, contaminant transport, groundwater flow, mass transport.

Suskin V. V., Kapyrin I. V., Boldyrev K. A. Near and Far Fields of a Radioactive Waste Disposal Facilities: Approaches to their Modeling Based on the GeRa Software. Radioactive Waste, 2023, no. 3 (24), pp. 117—125. DOI: 10.25283/2587-9707-2023-3-117-125. (In Russian).