Comparison between the geological settings of the Varbitsa (NW Bulgaria) and Bure (SE France) sites for geological disposal of radioactive waste

Geological settings are of major importance in selecting appropriate environment for disposal of high-level radioactive waste from nuclear power plants. Clay rocks are preferred in a number of countries as a suitable host rocks due to their insulating properties and ability to self- seal cracks and other disturbances. In Bulgaria, on the basis of multi-criterion comparative analysis, several prospective sites have been selected for further consideration. One of them is the Varbitsa site located in the Fore-Balkan Unit. The marls of the Sumer Formation are the host rock. Similar clay host rocks for high-level radioactive waste disposal have been extensively studied in France, Switzerland and Belgium. In this context, the experience gained in these countries is particularly valuable for the further development of the geological disposal in Bulgaria. The current paper presents a comparison between the geological settings of the Varbitsa site (NW Bulgaria) and the Bure site (SE France), whose argillites are similar to the Bulgarian marls. The outcomes of this comparison would be useful for planning and conducting future research activities, as well as for the public acceptance of the geological disposal