Radioactive waste disposal is an intractable issue that many consider the Achilles’ heel of nuclear power.　Fukushima also exposes the problem of what to do with the used fuels that are generated, stored, and accumulated in power stations. This problem is not confined only to Fukushima in Japan but to all other nuclear power programs in the world including Korea. In fact, the US has the biggest used fuel inventory (>65,000 tons) of all civilian nuclear power programs worldwide. For the long term, the scientific and technical communities generally agree that nuclear wastes (ie, high-level wastes and used fuels) can be disposed of safely by deep geological burial in suitable hard rock, salt or clay formations. The US abandoned its 20+ year effort for a geologic repository in Yucca Mountain, but Finland and Sweden continue to develop mined repositories to dispose of their used fuels.

The debates on used fuel management have been focused on the handling of plutonium, a by-product of nuclear fission in reactors. Countries concerned with the possibility of misuse of plutonium (for nuclear weapons) prefer a once-through approach including the direct disposal of used fuel, while other countries considering plutonium as a future energy resource (for fast reactors) advocate reprocessing and recycling. These debates have ignored the fact that only 0.5% of the used fuel content needs to be disposed of in deep geologic formations such as boreholes. The rest (95% of uranium and 3.5% of short-lived by products) does not pose the hazard warranting deep geologic disposal. Plutonium, comprising about 1% of used fuel, could be utilized in a fleet of economically viable fast reactors (if and when they are available) or it can also be disposed of in deep boreholes. The deep borehole technology to depths of 5 to 10 km has been demonstrated in the oil/gas industry and is readily available. The disposal of the 0.5% long-lived and heat-generating wastes in deep boreholes can permanently isolate such wastes from humans in small geographic foot-prints that can minimize or eliminate the NIMBY concern.

A solution to waste disposal is the biggest confidence-building measure needed for public acceptance of future nuclear power development.