Abstract:
We report the outcome of high-temperature, high-pressure experiments showing that granite can be partially melted and completely recrystallized on a time scale of years as opposed to millennia as widely believed. This could prove the key to secure, very deep borehole disposal in the continental crust for small to moderate volumes of particularly problematic radionuclides. Removal of these problematic isotopes from spent nuclear fuel and other forms of high-level waste could open the way to safe and acceptable disposal of the remaining bulk of high-level waste with large volumes of intermediate-level waste in geologically shallow, conventional repositories. [PUBLICATION ABSTRACT]