Over the past two decades, the safety case has become a powerful and essential tool to support decision making at every stage of a geological disposal programme. Now, an increasing number of national programmes are advancing towards licensing, opening the door to the concrete realisation of their deep geological repository (DGR) for high-level radioactive waste. This achievement marks the culmination of the evolution and periodic updating of the safety case as an iterative process of site characterisation, design development and demonstration, RD&D, safety assessment and integration, generally spanning over multiple decades, accompanied by regulatory reviews and ongoing communication with involved stakeholders. During this process the entire lifecycle of the waste - from its generation to its ultimate disposal - is duly considered. Of particular importance is the embedding of optimisation within the process, so as to achieve safety, technical feasibility, sustainability and to fulfil stakeholder expectations and requirements.

This stepwise process following the holistic approach to waste management entails, amongst others, the transfer of information between the different stages of waste generation and management, in the form of data, criteria, liabilities, decisions and requirements. It implies that the safety case, first developed at the early stages of a programme, contains within it the structure and essential elements to be further developed and deployed at later stages of the programme. Safety case digitalisation, as well as knowledge preservation and transfer through expert generations, are key for the successful iteration of the safety case towards implementation. 

The maturity of the safety case concept as developed by the NEA Integration Group for the Safety Case (IGSC) and national and international programmes has reached a high level, providing the basis to explore new domains, such as gathering and using experience obtained from already-operating repositories for other types of radioactive waste, including insights on operational issues and waste acceptance, as well as transfering the safety case methodologies to other disposal concepts.

The symposium is now the fourth in a series IGSC has been organising since 2007, in co‑operation with other international organisations. It will provide a forum in which these topics can be addressed, with presentations from programmes at different stages and extensive discussions about the issues raised. Symposium participants will also be informed about the status of new activities of the IGSC 2023-2025 Programme of Work currently under way.

In view of this, the objectives of the forthcoming IGSC symposium are to:

• identify the key to a safety case that supports successful licencing steps, examining the lessons learned and the challenges faced in this regard by advanced DGR programmes;
• understand how a safety case evolves through the successive key milestones in a disposal programme, from the generic through to the site-specific stage, and finally to implementation, including the adaptation of the safety case to an evolving regulatory framework;
• explore the role of specific features, such as requirements management systems and information, data and knowledge management (IDKM) in building a safety case and in supporting its evolution throughout successive key milestones in a disposal programme, including the development of digital safety cases;
• practically apply knowledge sharing by involving young scientists in the symposium, exchange knowledge and discuss their views, ideas and expectations;
• carry on further from the 2022 NEA workshop on development of safety cases for different types of disposal facilities, exchanging experience with other non-DGR disposal facilities will be addressed, especially concerning the application of holistic approaches to waste management.
  • the involvement of different type of stakeholders, particularly the communication of the safety case with them;
  • key challenges faced at different stages, including interaction with regulatory bodies, operational safety, waste acceptance, the management of uncertainty and the development and maintenance of a safety culture.

Manuel CAPOUET (ONDRAF/NIRAS)
Noseck ULRICH (GRS)
Alexander CARTER (NWS)
Peter MOLNAR (PURAM)
Thomas KAEMPFER (NAGRA)
Ann-Kathrin LEUZ (ENSI)
Lucy BAILEY (NWS)
Doug ILETT (Env. Agency)
Jens MIBUS (BASE)
Frederic BERNIER (FANC)
Tom PEAKE (EPA)
Julie BROWN (CNSC)
Sylvie VOINIS (Andra)
Vladimir LEBEDEV (OECD NEA)
Zhuoran LI (OECD NEA)
Rebecca TADESSE (OECD NEA)

Registration for the workshop is due to open in Fall 2023, via this page.

Photo by Kate Kasiutich on Unsplash