INFLUENCE OF DEGRADED CEMENT BACKFILL ON RADIONUCLIDE RELEASE CONSIDERING RW CLASS 1 DISPOSAL IN SUPER-CONTAINERS

The paper evaluates the influence of degraded cement backfill on contaminant release for geological radioactive waste disposal concept assuming that the waste surrounded by compacted bentonite is emplaced in “supercontainers” into vertical boreholes within cement backfill. The paper demonstrates that simple compartment and more precise 3D-model assessments yield similar results. It also shows how the calculations are affected by mesh discretization and ground water flow in degraded backfill. Considering moderate rock suitability criteria, degraded backfill increases maximum contaminant release not more than by an order of magnitude, which is substantially less compared to other safety assessment uncertainties.

Keywords: radwaste geological disposal, crystalline rock, “supercontainer” with compact bentonite, cement backfill, advective transport, diffusion transport, radioactive waste.

Bogatov S. A., Grigorev F. V. Influence of Degraded Cement Backfill on Radionuclide Release Considering RW Class 1 Disposal in Super-Containers. Radioactive Waste, 2022, no. 1 (18), pp. 77—85. DOI: 10.25283/2587-9707-2022-1-77-85. (In Russian).