What is the goal of the project?

The aim is to contribute to the scientific research on repositories of burnt-up nuclear fuel in the Czech Republic and in the world and to the search of a suitable locality for the fuel’s storage by defining the characteristics of the geochemical barrier. The term geochemical barrier comprises a set of characteristics of the geological environment (and its geochemical characteristics especially) which will block uranium’s escape from the repository to its surroundings on its own, via natural processes. This definition can lead to a significant increase in efficiency while searching for a suitable locality for theconstruction of the burn-up fuel repository in the Czech Republic.

The Rožná deposit which is currently being closed down represents a unique environment for the planned research. The deposit was formed 270 ma and held uranium in its stable state until present.

The aim of the project is to obtain new data which will enable us to understand the conditions under which uranium will be stable, via the study of a natural analogue – the Rožná uranium deposit, through the cooperation of three organisations which are involved in long-term research of the topic (Faculty of Science of the MU, DIAMO, s.p., and SÚRAO). The stable conditions will translate into the fundamental parameters of the geochemical barrier blocking the migration of radioactive elements from the repository to the surrounding environment. To achieve this, the current knowledge related to the deposit such as its formational mechanisms, the properties of its surrounding geological environment which has acted as a geochemical barrier, and its long-term development must be deepened.

It can be expected that the geological environment of the repository defined by similar properties to the geological environment of the deposit will act as a natural geochemical barrier thus blocking uranium’s migration to the adjacent areas. The Rožná deposit also provides, thanks to its long-term operation, a unique opportunity to study the migration of uranium as it is taking place in a real rock and water space under conditions which are comparable to the conditions in the planned deep repository. The mode of operation and closure including changes in redox conditions and hydrogeological regime is virtually the same as it is during the construction, operation and closure of a deep nuclear waste repository.