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Bajwa C.,International Atomic Energy Agency | Pope R.,Federal Agency for Nuclear Control | Zhao Y.,Ministry of Environmental Protection
Packaging, Transport, Storage and Security of Radioactive Material | Year: 2013

The International Atomic Energy Agency (IAEA) is responsible for developing safety requirements for the transport of radioactive material. These requirements were first published in 1961 as 'Regulations for the Safe Transport of Radioactive Material', Safety Series No. 6 (the Regulations), and have been revised at regular intervals, in consultation with Member States, and with input from other relevant organisations, as appropriate. The current regular review and revision of the Regulations has been driven by problems, challenges and the demand for improvements, as well as the need to take into account experiences in transport, newly identified issues, new technologies, best practices, the demand for sustainable transport and harmonisation. After 50 years, 15 editions of the Regulations have been published. With the passage of time, the scientific and technical heritage of several decades of development in transport safety has begun to fade. The need to capture valuable knowledge, which needs to be preserved for future reference, has become clear. In general, every requirement in the regulations was developed on the basis of deliberations among international experts and an appropriate technical basis. The knowledge bases for these often exist in a decentralised manner in many Member States with mature nuclear programmes. Easier access to the existing technical bases for the Regulations could lead to a more comprehensive understanding of the Regulations. Knowledge capture and transfer can contribute to the development of and innovations in transport safety. This paper provides an overview of international level efforts that began in 2010 to develop a comprehensive and detailed technical basis document (TecBasDoc) to support the current and future revisions of the Regulations. The draft TecBasDoc has so far resulted from efforts by IAEA staff and a large number of international transport experts. It exceeds 150 pages in length using, to the greatest extent possible, historical documents dating as far back as the 1950s as reference material. The intent of this effort is to record, for those Member States new to transport and for future generations, the scientific and technical heritage of several decades of development that has occurred in transport safety and to capture valuable knowledge so it can be preserved for future reference. The latest effort has involved consultants to the IAEA adapting the draft to reflect guidance from the IAEA's Transport Safety Standards Committee (TRANSSC) and delving into the IAEA's archives and other sources of historical documents, searching out many long sought, older supporting documents. The draft is currently structured into 12 chapters, embodying multiple supporting appendixes. This paper elaborates on the first chapters of the document, which include General History, Fundamental Safety Principles, Safety Objectives and Principles for Transport, General Safety Requirements, Radiation Protection and Controls for Transport. Two companion papers at PATRAM 2013 address the status of the TecBasDoc in the topical areas of package testing and criticality control. In all cases, the chapters of the TecBasDoc address how early decisions were made citing well known historical experts and discussing how these initial decisions have been adapted to meet the emerging international safety guidelines. © 2014 W. S. Maney & Son Ltd. Source


Gedeon M.,Belgian Nuclear Research Center | Wemaere I.,Belgian Nuclear Research Center | Wemaere I.,Federal Agency for Nuclear Control | Labat S.,Belgian Nuclear Research Center
Physics and Chemistry of the Earth | Year: 2011

Since 1975, the possibility to dispose of high-level radioactive waste in the Boom Clay formation has been investigated in Belgium at the test site in Mol. This research involves detailed studies of the hydrogeological system at various scales, observations of groundwater levels in the regional and local piezometric networks, several site investigations including geophysics and core-drilled boreholes. The knowledge gained during the long-term hydrogeological research is integrated in groundwater models. Major differences in the groundwater regimes above and below the Boom Clay gave rise to two models simulating these two sub-systems separately. The Neogene aquifer model is used to simulate the groundwater flow above the Boom Clay and the Deep aquifer pumping model to simulate the groundwater flow below the Boom Clay. The regional groundwater research improved the understanding of the regional flow system, since it has enabled to explain the behaviour of the aquifer system using a combination of a steady-state model for the Neogene aquifers and a transient model for the deep aquifers. This combination of modelling tools can offer a representative set of boundary conditions for the consecutive models that will depend on the scenarios required for the performance assessment of the integrated repository system. © 2011 Elsevier Ltd. Source


Malone J.,Trinity College Dublin | Del Rosario-Perez M.,World Health Organization | Van Bladel L.,Federal Agency for Nuclear Control | Jung S.E.,Catholic University of Korea | And 2 more authors.
Journal of the American College of Radiology | Year: 2015

A recent international meeting was convened by two United Nations bodies to focus on international collaboration on clinical appropriateness/referral guidelines for use in medical imaging. This paper, the second of 4 from this technical meeting, addresses barriers to the successful development/deployment of clinical imaging guidelines and means of overcoming them. It reflects the discussions of the attendees, and the issues identified are treated under 7 headings: ▪ Practical Strategy for Development and Deployment of Guidelines; ▪ Governance Arrangements and Concerns with Deployment of Guidelines; ▪ Finance, Sustainability, Reimbursement, and Related Issues; ▪ Identifying Benefits and Radiation Risks from Radiological Examinations; ▪ Information Given to Patients and the Public, and Consent Issues; ▪ Special Concerns Related to Pregnancy; and ▪ The Research Agenda. Examples of topics identified include the observation that guideline development is a global task and there is no case for continuing it as the project of the few professional organizations that have been brave enough to make the long-term commitment required. Advocacy for guidelines should include the expectations that they will facilitate: (1) better health care delivery; (2) lower cost of that delivery; with (3) reduced radiation dose and associated health risks. Radiation protection issues should not be isolated; rather, they should be integrated with the overall health care picture. The type of dose/radiation risk information to be provided with guidelines should include the uncertainty involved and advice on application of the precautionary principle with patients. This principle may be taken as an extension of the well-established medical principle of "first do no harm." © 2015 Published by Elsevier Inc. on behalf of American College of Radiology. Source


Jacops E.,Belgian Nuclear Research Center | Volckaert G.,Belgian Nuclear Research Center | Volckaert G.,Federal Agency for Nuclear Control | Maes N.,Belgian Nuclear Research Center | And 2 more authors.
Applied Clay Science | Year: 2013

Boom Clay is presently studied as the reference host formation for the disposal of high-level and long-lived radioactive waste in Belgium. In a geological repository, the production of gas is unavoidable. Gas is produced by different mechanisms: anaerobic corrosion of metals in waste and packaging, radiolysis of water and organic materials in the packages and microbial degradation of various organic wastes. Corrosion and radiolysis yield mainly hydrogen while microbial degradation leads to methane and carbon dioxide. The generated gas will dissolve in the ground water. As transport in Boom Clay is dominated by diffusion, the dissolved gas is transported away from the repository by diffusion as dissolved species. If the rate of gas generation is larger than the diffusive flux into Boom Clay, the pore water within the disposal gallery will become oversaturated and a free gas phase might form. If the gas pressure keeps increasing, free gas ingress into Boom Clay will occur, most likely through creation of new pathways. In order to make a good evaluation of the balance between gas generation and gas dissipation through engineered barriers and host formation, good estimates for the gas diffusion coefficients of the gases are needed. The currently available gas diffusion parameters for hydrogen in Boom Clay suffer from a large uncertainty, and by application of conservative values for both the source term and the gas migration term the formation of a free gas phase can presently not be excluded for some waste types.In this study a versatile method was developed to determine more precisely the gas diffusion coefficient for dissolved gases in Boom Clay. For the development of the technique, He and CH4 were used.The proposed method is based on a through diffusion methodology and allows for two dissolved gases to diffuse through a clay sample at the same time. From the evolution of the diffusant concentration in both compartments, the apparent diffusion coefficients of dissolved He and CH4 were obtained: 12.2×10-10 and 2.42×10-10m2/s, with uncertainties of 10%, respectively. © 2013 Elsevier B.V. Source


Grant
Agency: Cordis | Branch: FP7 | Program: CP-IP | Phase: Fission-2008-1.1.1 | Award Amount: 11.63M | Year: 2009

The multiple barrier concept is the cornerstone of all proposed schemes for underground disposal of radioactive wastes. The concept invokes a series of barriers, both engineered and natural, between the waste and the surface. Achieving this concept is the primary objective of all disposal programmes, from site appraisal and characterisation to repository design and construction. However, the performance of the repository as a whole (waste, buffer, engineering disturbed zone, host rock), and in particular its gas transport properties, are still poorly understood. Issues still to be adequately examined that relate to understanding basic processes include: dilational versus visco-capillary flow mechanisms; long-term integrity of seals, in particular gas flow along contacts; role of the EDZ as a conduit for preferential flow; laboratory to field up-scaling. Understanding gas generation and migration is thus vital in the quantitative assessment of repositories and is the focus of the research in this proposal for an integrated, multi-disciplinary project. The FORGE proposal is for a pan-European project with links to international radioactive waste management organisations, regulators and academia, specifically designed to tackle the key research issues associated with the generation and movement of repository gasses. Of particular importance are the long-term performance of bentonite buffers, plastic clays, indurated mudrocks and crystalline formations. Further experimental data are required to reduce uncertainty relating to the quantitative treatment of gas in performance assessment. FORGE will address these issues through a series of laboratory and field-scale experiments, including the development of new methods for up-scaling allowing the optimisation of concepts through detailed scenario analysis. The FORGE partners are committed to training and CPD through a broad portfolio of training opportunities and initiatives which form a significant part of the project.

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