PRELIMINARY ASSESSMENT OF ENGINEERED BARRIER PARAMETERS UNDER DGR CONCEPT WITH HORIZONTAL ORIENTATION OF RW PACKAGES IN COPPER COATED CONTAINERS

The paper discusses a DGR concept providing for heat-generating radioactive waste (RW) disposal in relatively thinwalled steel containers with a copper coating in packages of compacted bentonite blocks installed into horizontal drifts. The study assumes that this DGR layout should provide safe disposal of historical RW Class 1 with relatively low activity and heat generation levels. The proposed concept imposes appropriate restrictions on the bentonite buffer, among which the paper quantitatively considers the thickness varying depending on the residual RW heat release, the minimum bulk density, as well as the content and type of montmorillonite. For further assessment purposes, the paper proposes to consider bentonite blocks made of compacted bentonite from Russian deposits with a predominant content of sodium montmorillonite characterized with minimum required bulk density. The authors also proposed to fill the gaps between RW packages made of compacted bentonite and drifts with pellets. Such bentonite pellets should have maximum achievable bulk density and a predominant content of calcium montmorillonite.

Keywords: radioactive waste, clay materials, nuclear legacy facilities, RW disposal, engineered barriers.

Bogatov S. A., Drobyishevskiy N. I., Krupskaya V. V., Zakusin S. V., Lekhov V. A. Preliminary Assessment of Engineered Barrier Parameters under DGR Concept with Horizontal Orientation of RW Packages in Copper Coated Containers. Radioactive Waste, 2023, no. 3 (24), pp. 77—91. DOI: 10.25283/2587-9707-2023-3-77-91. (In Russian).