The disposal of radioactive waste is a central issue in the future of nuclear power and poses considerable technical, political and social issues. This book addresses these topics in an integrated fashion using performance assessment of the disposal concept as a unifying theme. Subjects addressed include: regulatory criteria; waste types, sources and characteristics; man-made or "engineered" barriers; the selection and evaluation of geological disposal media; the use of underground research laboratories; the movement of radionuclides in the biosphere; repository performance assessment tools and approaches; addressing uncertainty and spatial variability; assessing information from natural systems; and looking at radioactive waste in relation to other wastes. The book provides an up-to-date picture of radioactive waste disposal issues and will be of interest to scientists, engineers and consultants working in the nuclear industry and the environmental field.