Nuclear waste disposal - groundwater contamination in three dimensions

This review of groundwater contamination above and below nuclear waste repositories deals with a wide range of geological settings. The best studied systems are repositories in tuffite, basalt, granitoid and salt. Low-permeability flood basalt is a good proxy for low-permeability clay though not studied in detail. There are two distinct groups of nuclear-waste disposal projects: (1) geological repositories that have an engineered barrier designed to last for the whole lifetime of the repository and (2) geological repositories that have an engineered barrier designed to fail long before the waste becomes harmless. Groundwater contamination in the first case is by accident only. This may be a production defect in the waste package or emplacement error. In the second case, groundwater contamination, which is planned, is much higher than that in the first case.