One of the greatest difficulties is how to prevent chemical reactions from occurring along the intermediate-level waste. In Carlsbad, New Mexico, there was a drum that exploded and turned into a flame-thrower. Radioactive dust went 750 metres up the shaft and contaminated 22 workers. This is because of chemical reactions. Chemical reactions can occur that then spread radioactive waste. This is a big problem over the long term.
On June 9th, 2022. See this statement in context.