IAEA-TECDOC-1537 Strategy and Methodology for Radioactive Waste Characterization March 2007 IAEA-TECDOC-1537 Strategy and Methodology for Radioactive Waste Characterization March 2007 The originating Section of this publication in the IAEA was: Waste Technology Section International Atomic Energy Agency Wagramer Strasse 5 P.O. Box 100 A-1400 Vienna, Austria STRATEGY AND METHODOLOGY FOR RADIOACTIVE WASTE CHARACTERIZATION IAEA, VIENNA, 2007 IAEA-TECDOC-1537 ISBN 92–0–100207–6 ISSN 1011–4289 © IAEA, 2007 Printed by the IAEA in Austria March 2007 FOREWORD Radioactive waste management requires planned and systematic actions to provide confidence that the entire system, processes and final products will satisfy given requirements for quality. In order to ensure a quality end product, it is absolutely necessary to know and control the chemical and radiochemical parameters within the entire waste management life cycle, with special emphasis on waste conditioning, storage and disposal. Testing and analyses to demonstrate the radioactive content and the quality of final waste forms and waste packages are key components of this knowledge and control and are essential to accurate characterization of the waste. Reliable and effective methods for measuring radiological, physical, chemical, radiochemical and other characteristics have been established in many Member States, and the IAEA has several technical reports series on the subject. However, none of the existing IAEA publications has attempted to present a strategy and methodology for waste characterization which takes into account the origin of the waste, the different waste streams, the situation of the analytical laboratories, and the analytical technologies and techniques available. Neither has any attempt been made to offer any selection of standards that are used in the radio- analysis laboratories. To cover this gap, the IAEA initiated a task that was intended to give recommendations on harmonization in waste characterization. During drafting, the scope was appropriately expanded to provide a more comprehensive examination of strategies for radioactive waste characterization. The preparation of the report was accomplished through two consultant meetings in November 2002 and March 2004, along with one technical meeting held in March 2003. A final comprehensive review was performed August–September 2006 to verify the information remained current and relevant prior to publication. In total, 19 experts from 13 Member States and the IAEA participated at different stages in the development process. The IAEA wishes to express its appreciation to all those individuals who took part in the preparation and publication of this report. Particular acknowledgement is due to P. Van Iseghem, Belgium, who chaired both consultants meetings and the technical meeting, as well as contributing great effort toward the completion and technical review. The officer at the IAEA responsible for initiating this report was R. Burcl of the Division of Nuclear Fuel Cycle and Waste Technology. J.L. González Gómez and J.J. Kelly of the same division finalized the report for publication. EDITORIAL NOTE The use of particular designations of countries or territories does not imply any judgement by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries. The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA. CONTENTS SUMMARY ............................................................................................................................... 1 1. INTRODUCTION ............................................................................................................ 3 1.1. Background ............................................................................................................ 3 1.2. Objective ................................................................................................................ 3 1.3. Scope ......................................................................................................................4 1.4. Structure ................................................................................................................. 4 2. STRATEGY IN DEFINING THE CHARACTERIZATION PROGRAMME................ 5 2.1. Background ............................................................................................................ 5 2.2. Types of waste........................................................................................................ 6 2.2.1. Definitions of new waste and historical waste ........................................... 6 2.2.2. Waste subtypes........................................................................................... 7 2.3. Requirements........................................................................................................ 10 2.4. Life cycle.............................................................................................................. 10 2.4.1. Planning and Waste Generation ............................................................... 11 2.4.2. Treatment ................................................................................................. 12 2.4.3. Conditioning............................................................................................. 12 2.4.4. Storage and disposal................................................................................. 12 2.5. Development of characterization programme strategy......................................... 13 2.5.1. Principle issues and development of waste acceptance criteria ............... 13 2.5.2. Elements of characterization programmes ............................................... 14 2.5.3. Quality assurance and quality control ...................................................... 15 2.6. Organization and responsibility............................................................................ 15 2.6.1. Responsibilities of the regulator/licensing authority................................ 16 2.6.2. Responsibilities of the generator of the waste.......................................... 16 2.6.3. Responsibilities of the treatment/conditioning/storage operator.............. 17 2.6.4. Responsibilities of the operator of the disposal facility (operating company, agency).................................................................................... 17 2.6.5. Independent verification........................................................................... 18 2.7. Cost and benefits of waste characterization ......................................................... 19 2.7.1. Process knowledge ................................................................................... 19 2.7.2. Timing of waste characterization efforts.................................................. 20 3. IMPORTANT FACTORS TO CONSIDER IN DEFINING A WASTE CHARACTERIZATION PLAN..................................................................................... 20 3.1. Scaling factor methodology.................................................................................. 20 3.2. Accuracy considerations....................................................................................... 21 3.2.1. Introduction .............................................................................................. 21 3.2.2. Checking the homogeneity of a waste stream and sampling.................... 22 3.2.3. Selection of the key nuclides.................................................................... 24 3.2.4. Measurement methods.............................................................................. 24 3.2.5. Reference materials, proficiency tests; associated traceability................. 28 3.2.6. Consensus standards................................................................................. 36 3.3. Calculation and model uncertainty....................................................................... 37 3.4. Uncertainty propagation ....................................................................................... 39 4. CHARACTERIZATION METHODOLOGY APPLICATION TO THE DIFFERENT WASTE CATEGORIES .......................................................................... 43 4.1. Introduction/applicability of scaling factor method ............................................. 43 4.2. Simple and stable waste streams .......................................................................... 45 4.2.1. Enrichment, conversion, fuel fabrication ................................................. 45 4.2.2. Nuclear power plant ................................................................................. 48 4.2.3. Spent fuel.................................................................................................. 49 4.3. Complex and stable waste streams....................................................................... 50 4.3.1. Nuclear power plant ................................................................................. 50 4.3.2. Reprocessing ............................................................................................ 50 4.3.3. Waste form............................................................................................... 54 4.4. Simple and variable waste streams — Examples of nuclear research