Waste Technology Section

Predisposal Management of Radioactive Waste


Recently Completed Activities

 

Improvement of Radioactive Waste Management at WWER Nuclear Power Plants, TECDOC-1492, April 2006

This document covers the important aspects applicable to the improvement of waste management at WWER NPP, including both plant-level and country-level considerations. The major issues addressed are:


Innovative Waste Treatment and Conditioning Technologies at Nuclear Power Plants, TECDOC-1504, July 2006

This publication provides an overview of the innovative technologies currently employed at or in support of NPP, including the applicable waste streams, benefits and impacts of each technology, current applications within the nuclear community (who is using the technology), and any non-technical innovative approaches for key decision-makers. The purpose of the publication is to provide reactor designers and decision-makers at nuclear power plants (NPP) and other involved bodies with technologically oriented information on recent achievements in innovative processing of liquid, semi-liquid and solid wastes, and of their potential use. This publication is an attempt to highlight those technologies deserving of further consideration and more widespread application.

The focus is on LILW for water cooled reactors. This includes existing plants which are operational or in decommissioning. It also includes advanced nuclear plants which are under construction or being considered for construction. It is noted that many of the technologies and approaches described are also applicable to other reactor types (e.g., gas-cooled reactors).


Retrieval of Fluidizable Radioactive Wastes from Storage Facilities, TECDOC-1518, August 2006

This report provides guidance for strategic planning and implementation of re-suspension and retrieval of stored fluid or fluidizable radioactive wastes. The potential risks associated with preparation and realization of these processes are included in the report, and lessons learned from previous applications are highlighted.

This report divides successful retrieval of radioactive waste into two areas. The first area applies the concept of the waste retrieval as being the final component of a systematic process of old waste management. It also encompasses characterization as it applies to waste retrieval and downstream processes, including acceptance of wastes for treatment, conditioning, storage or disposal. This retrieval stage or concept should be in conformity with national policy, as well as complying with international safety standards and environmental agreements. The second area of the report focuses on implementation of waste retrieval in a wide range of scenarios and using a wide range of retrieval approaches, equipment and technologies.

Technological procedures and equipment used in various countries for re-suspension and remobilisation of stored fluidizable radioactive wastes are described in the annexes of the TECDOC as potential options.


Characterization, Treatment and Conditioning of Radioactive Graphite from Decommissioning of Nuclear Reactors, TECDOC-1521, September 2006

Worldwide, there are more than 230,000 tonnes of radioactive graphite which will eventually need to be managed as radioactive waste. Proper management of radioactive graphite waste requires complex planning and the implementation of several interrelated operations. The challenges imposed for radioactive graphite waste management are numerous and complex. There are no universally accepted decisions on treatment and conditioning methodologies at present, although it is clear that disposal will be either in an intermediate depth repository or a deep geological repository. There are two basic options for graphite waste management: (1) packaging of non-conditioned graphite waste with subsequent direct disposal of the waste packages, and (2) conditioning of graphite waste (principally either by incineration or calcination) with separate disposal of any waste products produced, such as incinerator ash. In both cases, the specific properties of graphite—such as Wigner energy, graphite dust explosibility, and radioactive gases released from waste graphite—have a potential impact on the safety of radioactive graphite waste management and need to be carefully considered.

This publication addresses storage and disposal of graphite waste, but only in terms of their relationship to characterization, treatment and conditioning. In most cases, design, construction and licensing of a disposal repository for radioactive graphite is still pending, and at present, the most common approach is to rely on ´safe enclosureˇ of graphite in existing facilities.


Development of Specifications for Radioactive Waste Packages, TECDOC-1515, October 2006

In the management of radioactive waste, a waste package is designed as the major engineered component for ensuring containment and providing safety functions. It also represents a principal unit used as a reference for controlling information, record keeping, and making decisions with due considerations of the interdependencies, impacts and information needs at various stages in radioactive waste management.

This publication covers development and implementation of waste package specifications for various types of waste and various kinds of waste packages. The emphasis is on selection of proper waste package characteristics, including content of radionuclides in the waste and other radiation safety parameters, physical and chemical properties of the solidified waste forms and canisters, and materials technology. Near surface and deep geological disposal options are also covered as they relate to waste package specifications.

This report provides guidance for developing waste package specifications by using a systematic stepped approach, integrating the technical, organizational and administrative factors that need to be considered at each step of planning and implementing waste package fabrication, approval and control. The report reflects the considerable experience and knowledge that has been accumulated in the Member States and is consistent with the current international requirements, principles, standards and guidance for the safe management of radioactive waste. Relevant IAEA publications covering specific issues, such as regulatory requirements, waste package design, characterization, inspection and testing, transportation and storage, as well as safety assessments, surveillance and monitoring of disposal facilities, QA and QC procedures, and requirements for records maintenance, are referenced to provide further details on the activities linked to the development of waste package specifications.


Radioactive Sodium Waste Treatment and Conditioning, TECDOC-1534, January 2007

This publication provides a comprehensive review of worldwide management practices for sodium, NaK, mixtures of the two, and the arising radioactive wastes from nuclear facilities. This review includes:


Categorizing Operational Radioactive Wastes, TECDOC-1538, January 2007

This document refers to waste streams generated during operation of various nuclear facilities (such as nuclear power and research reactors), operation of fuel cycle facilities, and application of radionuclides in other fields (industry, research, education, medicine).

This publication provides a practical categorization approach that supports safe, cost effective radioactive waste management. The approach is based on waste stream segregation using two primary categories (unconditioned and conditioned wastes) and five subcategories (point of origin, physical state, type, properties, and process options). This publication seeks to improve communications among waste management professionals and Member States relative to the properties and status of radioactive waste. This is accomplished by providing a standardized approach to operational waste categorization using accepted industry practices and experience.


Strategy and Methodology for Radioactive Waste Characterization, TECDOC-1537, March 2007

This publication provides:


Waste Minimization Considerations at the Design Stage of Nuclear Facilities, TRS 460, December 2007

This publication identifies and outlines issues to be considered at the design stage of nuclear facilities to minimize future waste generation, facilitate future decommissioning, and optimize management of decommissioning and operational waste and materials.

Extensive research, development and analysis have been done on techniques used during decommissioning of old facilities and on evaluation of amounts and characteristics of both operational and decommissioning waste. Sufficient experience has also accumulated on practical decommissioning and management of associated waste and materials. Analysis shows that dismantling, decontamination and management of generated wastes could be optimized if this is properly considered at the design stage of a nuclear facility. Consideration of waste minimization, waste management, and decommissioning issues during the design stage influences the total economic and safety aspects facility operation and its post-operation management.


Chemical Durability and Performance Assessment under Simulated Repository Conditions, TECDOC-1663, October 2007

This CRP, which began in 1998 and was completed in 2004, continued the work of an earlier CRP on Performance of High Level Waste (HLW) Forms and Packages under Repository Conditions.

Experimental work carried out under the CRP focussed on the formulation and analysis of samples of real and simulated HLW and irradiated fuel, especially radionuclide leaching behaviour under conditions representative of a repository environment. Modelling studies pertinent to the development of repository assessment methodologies also formed part of the work program.

The importance of this work can be seen in its stated objective of developing the scientific and technical basis for geological disposal to support safety and performance assessments. Types of HLW matrices investigated included spent fuel, glasses, and ceramics. During the period spanned by the two CRPs, glass technology came to be regarded as relatively mature and further development focussed on ceramic forms, such as synthetic rock (SYNROC). The range of materials, waste forms and anticipated repository conditions being considered in the programs of the participants made the comparison of results between investigators challenging.


New Developments and Improvements in Processing of ‘Problematic˙ Radioactive Waste Streams, TECDOC 1579, December 2007

This report is the result of a CRP involving 15 organizations from 13 Member States. In this report, processing options for a total of 27 problematic waste streams were identified and addressed. These waste streams covered an extremely broad spectrum, ranging from simple, one component aqueous solutions originating from a research laboratory to very complex aqueous concentrates of waste resulting from reprocessing activities or reactor operation. These challenging wastes included: waste contaminated by tritium, wastes containing transuranic elements, and solid health care waste.

A key element to the approach to solving the issues of problematic wastes is in having a diversity of options available. This TECDOC brings these options together to enable fruitful discussions, the assessment of the options and lessons learned, and to serve as a generator of ideas for the future.

Probably the most important observation –and conclusion - that can be made on the basis of the studies performed is this: multistage processes, aimed at breaking down the issues associated with ‘problematic˙ waste into ‘standard˙ issues in the initial stages of the sequence, generally seem to offer the most versatile and effective solutions to the treatment of ‘problematic˙ wastes. This approach enables the processing of such wastes, after a suitable waste-specific pre-treatment, by standard treatment technologies.


Retrieval, Restoration and Maintenance of Old Radioactive Waste Inventory Records, TECDOC-1548, 2007

This publication presents a comprehensive assessment of waste inventory records systems. A variety of circumstances that may require the records to be re-assessed or retrieved is discussed. The implementation of the waste inventory data retrieval process will vary depending on the specific situation in each country, but the basic approach described in this publication will be applicable for those facilities where loss or inadequacy of inventory records are observed. The guidance provided on the waste inventory data retrieval process is based on the experience gained and approaches employed in some Member States, as part of the overall upgrading programme at their storage or disposal facilities.


Determination and Use of Scaling Factors for Waste Characterization in Nuclear Power Plants, NE Series No. NW-T-1.18, April 2009

The NE Series report should assist the Member States in the application of scaling factor methodology for radionuclides difficult to measure in the different waste streams from nuclear power plants (NPPs) and waste arising from decommissioning of nuclear facilities.


Locating and Characterizing Disused Sealed Radioactive Sources in Historical Waste, NE Series No. NW-T-1.17, 2009

This publication provides information and guidance on methodologies and techniques which could be used to locate, identify and characterize disused, sealed radioactive sources on historical waste sites. The sealed and shielded nature of these sources often poses a significant challenge to their characterization and thus to the verification of historical radioactive waste inventory records. Therefore, to facilitate the safe and proper classification of such sources, this publication describes the advantages and disadvantages of a number of methods of characterization, as well as the situational applicability of each.


License Applications for Low and Intermediate Level Waste Predisposal Facilities: A Manual for Operators, In Print

This publication provides guidance to the operators (licensees) of radioactive waste processing and storage facilities on the detailed content of documents which should be submitted to the regulatory body in support of the application for authorization and the ways of obtaining the required information.