Storage Conception
Insulation of radioactive waste from environment and performance of requirements of supervisory bodies and legislation on required safety will be achieved in the deep repository by system of manifold engineering and natural barriers.
This so called multibarrier system is formed by:
- the fuel itself and by its cladding that resisted extreme conditions in reactor,
- treatment of waste into suitable form resistant against maceration by water,
- sheathing of treated waste and spent nuclear fuel into metallic containers resistant against corrosion,
- placement and sealing of containers with waste in adapted underground areas,
- filling the free space with materials, which will assure suitable mechanical and chemical properties of environment for a long term,
- host geological environment - principle barrier, which will form a safe and stable protection of the whole storage system.
Various geological environments are suitable for location of deep repository, as e.g. salt formations, sedimentary, crystalline or metamorphic rocks. Selection of candidate locality for deep geological repository is a very demanding process, accompanied with vast geological works. Locality must satisfy challenging requirements for long-term stability, facilitating hydro geological conditions, sufficient thermal conductivity of the rock and many other parameters.
Safety of storage must be proved convincingly even before its execution. Storage must be in compliance with requirements on radiation safety determined by legislation and supervisory bodies, it must respect requirements on preservation of environment and health.
