Scientific Highlights

Chemical reactions will change the nature of the deep repository and the surrounding rock (clay rock); that much is certain. But to what extent and with what impact on safety? Researchers from the Paul Scherrer Institute are looking to answer this question with the aid of a combination of experiments and computer simulations.

How do radioactive substances move through the host rock in a deep repository for nuclear waste? Researchers from the Diffusion Processes Group in the Laboratory of Waste Management at the Paul Scherrer Institute (PSI) have been investigating. The transport properties of negatively charged radionuclides, which are repelled by the negatively charged surfaces of clay minerals and thus hardly adhere to the rock, are well known. An EU project in which the PSI is also involved is now yielding similar insights into positively charged and therefore highly adherent radionuclides.

Radioactive waste from nuclear power plants, as well as from medical applications, industry and research, has to be isolated from the environment, particularly the habitat of humans, for a very long time. Specialists at PSI have been concerned with the safety issues surrounding safety certification for geological repositories for many years. Research at PSI focusses primarily on the physico-chemical processes inside such storage systems. The aim is to create a realistic description of the risks associated with storage of radioactive waste.