In relation to the disposal of radioactive waste, the multibarrier containment concept envisages a combination of natural and engineered barriers acting to ensure that radionuclides in the waste are isolated from the human environment. The aim is that if, far in the future, radionuclide releases should occur, these will have a negligible impact on human health. The paper describes the engineered barriers appropriate to a UK repository for intermediate level waste and the underlying research which has supported their development. These engineered barriers ensure that, overwhelmingly, radionuclides are contained sufficiently to decay to stable isotopes while still within the confines of a repository.
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