What lithologies are deemed most suitable for the storage of nuclear waste?

Question

I have visited storage- and test facilities that are within salt and clay (Opalinuston) lithologies. What are other lithologies that are considered for the storage of nuclear waste and what are their advantages?

Answer 1

Argillites and clays are considered to be suitable host rocks for the storage of nuclear waste. Compacted swelling clays, used as engineered barriers, are also considered for nuclear waste disposal. Other appropriate lithologies would include basalt, granite, salt deposits, and volcanic tuffs.