NUCLEAR SPENT FUEL MANAGEMENT EXPERIENCE AND OPTIONS A report by an Expert Group NUCLEAR ENERGY AGENCY ORGANISATION FOR ECONOMIC CO-OPERATION AND DEVELOPMENT Pursuant to article 1 of the Convention signed in Paris on 14th December,! 960, and which came into force on 30th September, 1961, the Organisation for Economic Co-operation and -Developrnmr(OECd) shall promote policies designed: - to achieve the highest sustainable economic growth and employment and a rising standard of living in Member countries, while maintaining financial stability, and thus to contribute to the development of the world economy; - to contribute to sound economic expansion in Member as well as non-member countries in the process of economic development; and - to contribute to the expansion of world trade on a multilateral, non-discriminatory basis in accordance with international obligations. The Signatories of the Convention on the OECD are Austria, Belgium, Canada, Denmark, France, the Federal Republic of Germany, Greece, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, Turkey, the United Kingdom and the United States. The following countries accedei subsequently to this Convention (the dates are those on which the instruments of accession were deposited): Japan (28th April, 1964), Finland (28th January, 1969), Australia (7th June, 1971) and New Zealand (29th May, 1973). The Socialist Federal Republic of Yugoslavia takes part in certain work of the OECD (agreement of 28th October, 1961). The OECD Nuclear Energy Agency I NEA) was established on 20th April, 1972, replacing OECD's European Nuclear Energy Agency (ENEA) on the adhesion of Japan as a full Member. NEA now groups all the European Member countries of OECD and Australia, Canada, Japan, and the United States. The Commission of the European Communities takes part in the work of the Agency. The primary objectives of NEA are to promote co-operation between its Member governments on the safety and regulatory aspects of nuclear development, and on assessing the future role of nuclear energy as a contributor to economic progress. This is achieved by: - encouraging harmonisation of governments' regulatory policies and practices in the nuclear field, with particular reference to the safety of nuclear installations, protection of man against ionising radiation and preservation of the environment, radioactive waste management, and nuclear third party liability and insurance; - keeping under review the technical and economic characteristics of nuclear power growth and of the nuclear fuel cycle, and assessing demand and supply for the different phases of the nuclear fuel cycle and the potential future contribution of nuclear power to overall emrgy demand; - developing exchanges of scientific and technical information on nuclear energy, particularly through participation in common services; - setting up international research and development programmes and undertakings jointly organised and operated by OECD countries. In these and related tasks. NEA works in close collaboration with the International Atomic Energy Agency in Vienna, with which it has concluded a Co-operation Agreement, as well as with other international organisations in the nuclear field. hifeht en frifKii* %o*% IC litre GESTION DU COMBUSTIBLE NUCLEAIRb IRRADIE EXPERIENCE ET OPTIONS ©OECD, 1986 Application for permission to reproduce or translate all or part of this publication should be made to: Head of Publications Service, OECD 2, rue Andre-Pascal. 75775 PARIS CEDEX 16, France. FOREWORD The purpote of this study is to review objectively each stage of spent fuel management, looking at past experience and future options. It attempts to explain why the experts are confident that spent fuel and high level radioactive wastes can be managed with acceptably low risks to man and the environment. The report has been prepared under the guidance of experts from 14 OECD countries and 4 international organisations. It represents their views and not necessarily those of Member governments or participating organisations. The original reference date for data in the report was 1984. However, it has been updated to include recently published data for 1985, to the extent practicable. ACKNOWLEDGEMENT The Working Group was assisted in drafting of much of the body of this report by two consultants, Mr. Richard Ivens of the United Kingdom and Mr. A. Redcn of France. The Working Group wishes to thank them for their sincere and valuable en'orts, and also to thank British Nuclear Fuels pic for agreeing to make Mr. Ivens available. 3 k TABLE OF CONTENTS EXECUTIVE SUMMARY 7 PHOTOGRAPHS 13 INTRODUCTION 17 1. SPENT FUEL MANAGEMENT OPTIONS 18 1.1 General 18 1.2 Background 18 1.3 Recent Trends 20 1.4 Summary of Available Options 22 2. CURRENT PRACTICE AND FUTURE PLANS 24 2.1 Spent Fuel Stooge 24 2.2 Reprocessing 23 2.3 Direct Disposal of Spent Fuel 28 3. REVIEW OF TECHNICAL ASPECTS 30 3.1 The Stages 30 3.2 Spent Fuel Transport 30 3.3 Storage of Spt it Fuel 32 3.4 Reprocessing 37 3.5 Disposal of Fix-nt Fuel and High Level Waste 43 4. NON-TECHNICAL FACTORS AND OUTLOOK 50 4.1 Relative Importance and Size of Nuclear Programme 50 4.2 Economic Aspects 51 4.3 Public Acceptance and Perception 51 4.4 International Commitments and Co-operation 53 4.5 Outlook , 53 REFERENCES 54 GENERAL REFERENCES 5 5 COUNTRY ANNEXES Belgium 58 Canada 60 Finland 65 Fiance 67 Germany, Federal Republic 75 Italy 80 Japan 82 Netherlands 90 Sweden 91 Switzerland % c »ted Kingdom 98 United States 106 ANNEX >» 'icipants in the Working Group 103 6 EXECUTIVE SUMMARY lahoduclion The management of spent nuclear fuel is a subject of substantial interest to those involved with nuclear power issues, whether in the role of government decision maker, technical specialist or interested member of the general public. This report draws on the knowledge of experts from fourteen OECD countries to put into perspective for all of these audiences some technical and non-technical factors regarding spent fuel management or, as it is sometimes called, the back-end of the fuel cycle. The report focusses on uranium dioxide (or just oxide) which is the form of fuel used by most commercial reactors now in operation. However, reference is also made to the significant amount of experience gained with reprocessing uranium metal fuel from gas-graphite reactors. Backgro—i The volume of spent fuel produced in the world's nuclear power reactors is remarkably small considering the amount of electricity generated. This fact has made it possible to store the spent fuel for long periods at relatively low cost. However, it is projected that by the year 2000 some 1 S3 000 tonnes of spent oxide fuel containing fission products, uranium and other associated heavy metals (plutonium and small quantities of heavier actinides), will have been generated in the OECD countries and inventories will continue to rise beyond the turn of the century. Interim storage cannot be extended indefinitely and eventually some form of permanent disposal will be necessary. There are only two definitive options available for permanent disposal: - direct disposal of suitably packaged (or conditioned) spent fuel as waste; - reprocessing the spent fuel to recover the useful products it contains (plutonium and unconsumed uranium), followed by disposal of the remaining waste products. In both cases the wastes -vill be disposed of in repositories where they will be kept isolated from the biosphere while their radioactivity decays to a level which no longer represents an unacceptable hazard to man or the environment. Detailed design of repositories for spent fuel will not differ markedly from those for reprocessing wastes as the technical aspects of the two options are similar in scope and magnitude. Thus, much of the research now under way on repositories would be applicable to either option and, as such, there is no technical necessity for a country to make a final decision on which alternative to follow at the time it commences disposal research. Interim storage will continue to be necessary, of course, either storage of spent fuel before reprocessing or direct disposal, or storage of the reprocessing waste products prior to their disposal. Current plans are for total storage times, in one form or the other, of 20 to 50 years prior to disposal. Interim storage of spent fuel for extended periods has been well demonstrated and, in terms of impact on the cost of electricity generation, it is not expensive. With either disposal option, relatively long period 7 reduce heat production and radiation levels of the wastes that must ultimately be managed. In the early years of nuclear power development, from the 1950s to the early 1970s, it was assumed that all spent fuel would be reprocessed to extend the world's fuel resource base. It was known that Fast Breeder Reactors (FBRs), utilizing plutonium from reprocessed spent fuel, could increase the power extracted from every kilogram of uranium mined by some fifty times compared to conventional (or thermal) reactors. Thus FBR development was started. Pilot and prototype units were built in some countries as it was thought that a growing number of commercial units of this type of reactor would be needed in the 1980s. These units were expected to be fuelled initially with plutonium extracted from the spent fuel of thermal reactors and later with self-generated plutonium. Consequently, reprocessing technology was developed and has now been established commer­ cially. Some countries chose to follow the reprocessing option, either through building their own reprocessing plants or through contracting for reprocessing services by other countries. However, in recent years the forecasts of the rate of uranium use have fallen significantly, in step with forecasts of reduced rates of growth for electricity and nuclear power, and additional large quantities of uranium have been discovered. This has reduced the urgency for breeder reactors and hence for widespread reprocessing.