CONSERVATIVE LONG-TERM NUCLEAR SAFETY ASSESSMENT OF A DEEP RADIOACTIVE WASTE DISPOSAL FACILITY

The distinctive characteristic of vitrified high-level waste (VHLW) is its high concentration of transuranic elements with long half-lives. This can lead to a potential violation of nuclear safety standards in the long run due to increased concentrations of fissile nuclei that are considered nuclear-hazardous. For three vitrification campaigns of HLW conducted at FSUE "PA "Mayak", the compositions of the HLW were determined long after their expected time of isolation at the disposal site were calculated using the TRACT nuclide kinetics program. Based on these VHLW compositions, conservative models of a well-designed disposal site were created and variant criticality calculations were performed using the TDMCC Monte Carlo program. The calculation results indicate that the system remained nuclear safe in the long-term.

Keywords: radioactive waste, vitrified high-level waste, transuranic nuclides, nuclear safety, criticality calculations, long-term period.

Kizub P. A., Kulish E. S., Blokhin P. A., Kozlov P. V. Conservative long-term nuclear safety assessment of a deep radioactive waste disposal facility. Radioactive Waste, 2024, no. 4 (29), pp. 88—94. DOI: 10.25283/2587 9707-2024-4-88-94. (In Russian).