Disposal of short-lived low- and intermediate-level waste: analysis of foreign experience

Abstract

The article summarizes and analyzes the main approaches and practical experience of foreign countries regarding the disposal of short-lived low- and medium-level waste. Their place in the category of low-level waste according to the recommended classification of the IAEA, for which disposal in near-surface storage facilities is provided, is shown. Currently, in countries that operate nuclear facilities and develop nuclear technologies, there is no one approach to the disposal of such waste. The type of repository and its structural and technological solutions are determined by the specifics of the waste itself, the nature of the site, the state strategy in the nuclear industry, as well as social and economic factors. To date, several types of storage facilities have been developed for the disposal of short-lived low- and medium-level waste: relatively simple trench-type near-surface storage facilities; modular-type near-surface storage facilities with a complicated system of engineering barriers and criteria for selecting containing rocks (natural barriers) compared to the trench type; geological storages, which are mainly built in mining operations with a complex system of tunnels and barrier protection. Bentonite clays are widely used as components of engineering barriers. In the simplest case of near-surface repositories, the bentonite layer serves as the base material of the repositories and helps to reduce filtration and increase the sorption of radionuclides and other components. In the organization of geological repositories, the bentonite layer contributes to the reduction of water filtration into the repositories, increases the sorption of radionuclides, prevents the destruction of concrete structures during a shift by containing rocks, and, in the event of the destruction of cement-concrete structures of engineering barriers, leads to a decrease in the removal of radionuclides from the repositories into the environment. The work gives examples of different types of storage facilities in countries around the world.