Radioactive Waste Forms For The Future

This volume presents a compilation of important information on the full range of radioactive waste forms that have been developed, or at least suggested, for the incorporation of high-level nuclear waste. Many of the results were published in the ''gray literature'' of final reports of national laboratories or in various, generally less available, proceedings volumes. This is the first publication to draw information on nuclear waste forms for high-level wastes together into a single volume. Although borosilicate glass has become the standard waste form, additional research in this compound is still necessary. With improved technology (particularly processing technologies) and with a more detailed knowledge of repository conditions, glasses and second generation waste forms with improved performance properties can be developed. Sustained research programs on nuclear waste form development will yield results that can only add to public confidence and the final, safe disposal of nuclear waste. The aim of this volume is to provide a 'spring board' for these future research efforts. A detailed presentation is given on the properties and performance of non-crystalline waste forms (borosilicate glass, sintered glass, and lead-iron phosphate glass), and crystalline waste forms (Synroc, tailored ceramics, TiO 2 - ceramic matrix, glass-ceramics and FUETAP concrete). A chapter on Novel Waste Forms reviews a number of methods that warrant further development because of their potential superior performance and unique applications. The final chapter includes a tabulated comparison of important waste form properties and an extended discussion on the corrosion process and radiation damage effects for each waste form. Of particular interest is a performance assessment of nuclear waste borosilicate glass and the crystalline ceramic Synroc. This is the first detailed attempt to compare these two important waste forms on the basis of their materials properties. The discussion emphasizes the difficulties in making such a comparison and details the types of data that are required. Each chapter has been written by an expert and includes a current compilation of waste form properties with an extensive list of references. This volume will provide a stimulus for future research as well as useful reference material for scientists working in the field of nuclear waste disposal and materials science.

"How can sites of waste disposal be marked to prevent contamination in the future? The United States government addressed this challenge in planning for nuclear waste repositories. Consulting with experts in imagining future scenarios, in language and communication, and in anthropology, the Department of Energy sought to develop plans that would satisfy demands from the Environmental Protection Agency for a marker system that would be effective long into the future. Expert consultants proposed two very different designs: one based on archaeological sites recognized as cultural heritage monuments; the other proposing that certain forms invoke universal feelings. The Department of Energy opted for a design based on archaeological ruins, cited as proof human-made markers could last and communicate warnings for thousands of years. This book explores the common sense assumptions the experts made about their archaeological models, and shows how they are contradicted by what archaeologists understand about these places and things. The book alternates between discussions of archaeological marker designs and reflections on the alternative proposal based on archetypes intended to arouse universal responses. Recognizing these archetype designs as similar in scale and form to Land Art projects, it compares the way government experts proposed their designs would work with views of modern artists and critics. Drawing on views of indigenous people who disproportionately are asked to accommodate such projects, the book explores concessions within the project that only oral transmission is likely to ensure such sites remain identifiable long into the future"--

This book describes repository solutions for all types of radioactive waste and residues in different geotechnical repository structures. The focus is initially on existing or planned final disposal sites in Germany and the process of finding sites. However, international comparisons are drawn, especially to locations in the US. This affects both the repository structures and the legal requirements. The radioactive substances considered include residues from uranium ore processing, as well as low and intermediate level radioactive waste up to heat generating, high level radioactive wastes, such as spent fuel and vitrified waste from reprocessing. In order to evaluate the repository structures and their inventories, a dimensionless radiotoxicity index Ai / Fi [activity of radionuclide quantity (Ai) related to the exemption limit of radionuclide (Fi)] has been introduced. This gives the reader a well-founded overview of the degree of inconsistency in the handling of safety requirements for the respective geotechnical environmental structures. This creates the necessary transparency on this issue, which has not been previously available and is required by stakeholders today. The long-term security, the duration of the observation period and the certainty of the safety prognosis are also discussed in the book as well as the participation of subsequent generations in current and possible future repositories. This is vital as nuclear energy will continue to be used worldwide in the long term. The international repository projects presented have all been subjected to the same evaluation criteria. This applies both to existing operational project as well as those about to be commissioned and the processes for seeking locations. Special attention has been paid to monitoring, both operational and long-term monitoring. This broad range of topics makes this book a very valuable read for both the interested public and the professional world.

The IAEA International Conference on Radioactive Waste Management: Solutions for a Sustainable Future brought together experts from Member States to share experiences in the management of radioactive waste, with the aim of increasing the visibility of progress, good practice, and effective solutions. The sustainable application of nuclear technologies for the benefit of humanity, in cancer therapy, generating low-carbon electricity, improving crop yields and many other applications is fully connected with the responsible management of waste. It is only through the effective, safe and secure implementation of radioactive waste management solutions that Member States can continue to benefit from nuclear technologies and nuclear energy production, and the papers contained within these proceedings will help promote the sharing of good practices and experiences and thereby to a more sustainable future.

This book recounts the issues raised and the viewpoints aired at a recent symposium on repository licensing. It summarizes the problems surrounding the setting of an Environmental Protection Agency standard for the release of radionuclides and the regulatory problems inherent in meeting such a standard. Symposium participants came from a variety of federal agencies and advisory groups, state governments, public interest groups, engineering firms, national laboratories, and foreign and international organizations. The book illustrates the strong feeling in the radioactive waste disposal community that changes must be made if the United States is to fulfill its promise of safe management of current and future nuclear waste.

The perception of radioactive waste as a major problem for the industrial world has developed only recently. Four decades ago the disposal of such waste was regarded as a relatively minor matter. Those were the heady days when nuclear fission seemed the answer to the world's energy needs: the two wartime bombs had demonstrated its awesome power, and now it was to be harnessed for the production of electricity, the excavation of canals, even the running of cars and airplanes. In all applications of fission some waste containing radioactive elements would be generated of course, but it seemed only a trivial annoyance, a problem whose solution could be deferred until the more exciting challenges of constructing reactors and devising more efficient weapons had been mastered. So waste accumulated, some in tanks and some buried in shallow trenches. These were recognized as only temporary, makeshift measures, because it was known that the debris would be hazardous to its surroundings for many thousands of years and hence that more permanent disposal would someday be needed. The difficulty of accomplishing this more lasting disposal only gradually became apparent. The difficulty has been compounded by uncertainty about the physiological effects oflow-Ievel radiation, by the inadequacy of detailed knowledge about the behavior of engineered and geologic materials over long periods under unusual conditions, and by the sensitization of popular fears about radiation in all its forms following widely publicized reactor accidents and leaks from waste storage sites.

Cementitious materials are an essential part in any radioactive waste disposal facility. Conditioning processes such as cementation are used to convert waste into a stable solid form that is insoluble and will prevent dispersion to the surrounding environment. It is incredibly important to understand the long-term behavior of these materials. This book summarises approaches and current practices in use of cementitious materials for nuclear waste immobilisation. It gives a unique description of the most important aspects of cements as nuclear waste forms: starting with a description of wastes, analyzing the cementitious systems used for immobilization and describing the technologies used, and ending with analysis of cementitious waste forms and their long term behavior in an envisaged disposal environment. Extensive research has been devoted to study the feasibility of using cement or cement based materials in immobilizing and solidifying different radioactive wastes. However, these research results are scattered. This work provides the reader with both the science and technology of the immobilization process, and the cementitious materials used to immobilize nuclear waste. It summarizes current knowledge in the field, and highlights important areas that need more investigation. The chapters include: Introduction, Portland cement, Alternative cements, Cement characterization and testing, Radioactive waste cementation, Waste cementation technology, Cementitious wasteform durability and performance assessment.

The separation of radioactive waste materials into their chemical components is at the heart of all efforts to reduce the volume of nuclear waste. In Chemical Separations in Nuclear Waste Management: The State of the Art and a Look to the Future, the authors discuss the present state and possible future directions of separations science and technology. The book presents an overview of the environmental legacy from nuclear weapons production in the United States and the former Soviet Union, the magnitude of the cleanup efforts that are underway in both countries, and the pivotal role played in these efforts by separations science. Needs that are specific to the future development of separations science and technology are emphasized. Contents:1. Overview of Chemical Separation Methods. II. The Environmental Legacy of the Cold War: Site Cleanup in the United States. III. Environmental Impacts of Separation Technologies in Russia. IV. Non-Aqueous Separation Methods. V. U.S.-Russian Cooperative Program in Research and Development of Chemical Separation Technologies. VI. Radiation Protection Aspects of Nuclear Waste Separations. VII. Accelerator-Driven Transmutation Technologies for Nuclear Waste Treatment.