A number of issues have to be addressed in all countries where deep nuclear waste deposits are under consideration: What geologic formations are suitable? What is the fundamental safety philosophy? What time periods have to be considered for proof of safety for long-living waste? What are the safety margins for radio-active release over long time periods? How to evaluate long-term stability of the repository? To what extent and for what time period is retrievability desirable and feasible? What kind of mining engineering approach is suitable? How to find a site for the repository? How to gain public acceptance for the waste disposal? What is an appropriate institutional setting for planning, building, regulating the processes?
I introduce briefly generally accepted principles related to disposals for long-living nuclear waste (deep geological deposits, barrier systems) and address then the aspects mentioned before and sketch the differences between various national approaches.