Geological disposal of radioactive wastes; opportunity or threat?

Geological disposal is internationally recognized as the preferred approach for disposing of the more hazardous types of radioactive waste, including heat generating waste and long-lived waste; i.e. spent nuclear fuel, high level waste from the reprocessing of nuclear fuel, and other radioactive waste that generates significant amounts of heat or that contains concentrations of long-lived radionuclides that are unsuitable for its disposal in near surface facilities. For this, clay-mineral rich formations are the subjects of advanced radioactive waste programs in several countries, principally because of their very low permeabilities and demonstrated capacities to retard by sorption most radionuclides. However, sensitivity analyses and uncertainty analyses should be undertaken to obtain an understanding of the performance of the geological disposal system and its components under a range of evolutions and events. This article reviews the conceptual basis for geological disposal and impact of geological environment, considers the geological challenges to developing geological disposal facilities and the uncertainties that have to be managed.

Keywords:

Radioactive waste , geological disposal facility , multi-barrier system