The analysis of geological formations from Romania available for disposal of spent nuclear fuel

The majority of countries possessing nuclear power industry has not yet decided upon the option about closing the nuclear cycle. There are still in progress projects concerning the final disposal, while worldwide it is not foreseen the reprocessing of the whole amount of reusable fissionable materials. The annual worldwide production of used nuclear fuel continues to be about 10 500 - 11 000 tones of heavy metal. The difficulties in designing used fuel final disposal repositories led to the design of some interim storage facilities, providing a satisfactory safety level for biosphere. On the other hand, regardless of the selected option we respect to closing the nuclear cycle, a final repository must exists, either for the high level wastes resulted from reprocessing the used nuclear fuel or for the used fuel considered radioactive waste. Although, presently, in Romania, the nuclear fuel extracted from the reactor after its 'useful life' is declared as radioactive waste, it may contain a certain amount of fissionable material that could be used in other types of reactors. This possibility implies taking into account the concept regarding the recovery of fuel after a certain period of time, although, by definition, final disposal means prevention of this possibility. The harmonization of the Romanian legislation with that of the European Community and the adhering to the European Conventions, poses among other issues the problem of the final disposal of the used nuclear fuel. Starting from these major requirements the paper presents the main aspects of the Project 011/11.10.2001, entitled 'Researches for the selection and preliminary characterization of the host rock for the final disposal of the used nuclear fuel', part of The National Research Program: Medium, Energy and Resources. A complex analysis regarding the implications on the design of the Used Nuclear Fuel Final Disposal Repository in Romania was performed, the analysis of the available geological formations for disposal being the major part of the whole program