| abstract |
Dangerous, toxic, and/or radioactive volatiles are produced from nuclear fission, nuclear decay, and/or as a byproduct from vitrification of radioactive wastes. Such volatiles are treated during and after vitrification of the radioactive waste, to be converted into fixed-chemicals, that are retained in, on, and/or proximate to a cold-cap located vertically above vitrified melt. The cold-cap may have one or more volatile fixing additives (VFAs) for retaining the fixed-chemicals. The VFAs are located in and/or the cold-cap. The vitrification may occur within at least one human-made cavern. The human-made cavern may be located within a deep geologic rock formation. The deep geologic rock formation may be located at least 2,000 feet below a terrestrial surface of the Earth. The human-made cavern may be formed by first drilling a wellbore from the terrestrial surface to the deep geologic rock formation and then underreaming the wellbore into the deep geologic rock formation. |