Integration Group for the Safety Case of Radioactive Waste Repositories (IGSC)

The Integration Group for the Safety Case (IGSC) is the main technical advisory body to the NEA Radioactive Waste Management Committee on the deep geological disposal of long-lived and high-level radioactive waste. The IGSC's work centres on methodologies and strategies for characterising and evaluating disposal sites as well as on repository safety assessment aspects for various waste types.

The IGSC takes initiatives in the area of confidence in repository technical safety cases and their underlying methodological and scientific bases to support decision-making in repository development. Each IGSC initiative can be classified into one of three categories, as set out below.

• Core activities, the results of which directly support higher level RWMC analyses:
  • Safety Case;
  • Integrated Performance Assessments of Deep Repositories (IPAG);
  • International Experiences in Safety Cases (INTESC);
  • Handling Timescales;
  • Geosphere Stability of Crystalline Rocks.
• Technical activities, the results of which are presented for information to the RWMC:
  • Approaches and Methods for Integrating Geologic Information in the Safety Case (AMIGO).
  • Engineered Barrier System;
  • GEOTRAP;
  • Biosphere role;
  • Scenario development.
• Co-operative projects that concern highly-specialised activities:
  • Clay Club;
  • Features events and processes (FEP) database;
  • Sorption;
  • Thermodynamic Database (TDB) project.

During its annual meetings the IGSC often holds a topical session on a subject of particular interest to its members. To date topical session have addressed:

• the role of the biosphere in a safety case (October 2001);
• the safety case in general (October 2001);
• the potential impacts on repository safety by a proposed partitioning and transmutation programme (November 2002);
• observations regarding the safety case in recent peer reviews of safety assessment studies (October 2003);
• the role of monitoring in a safety case (November 2004);
• the consideration of timescales in the post-closure safety of geological disposal of radioactive waste (November 2005);
• the handling of features, events and processes in the safety case (2006).

The 2007 topical session will be on the IGSC programme of work.

IGSC meetings and workshops

International Experience in Developing Safety Cases (INTESC)
1-3 October 2007
Paris, France

The aim of the workshop is to assess, based on the preliminary findings of the INTESC questionnaire results and the outcomes of other current NEA initiatives, the current state of the art in the development of safety cases and where areas of agreement and disagreement may exist. Workshop participants will also seek to identify and understand issues that may need further work by the IGSC. Participation in this workshop is limited to IGSC members.

Ninth Meeting of the NEA Integration Group for the Safety Case (IGSC)
24-26 October 2007
Issy-les-Moulineaux, France

IGSC Workshop on Stability and Buffering Capacity of the Geosphere for Long-term Isolation of Radioactive Waste: Application to Crystalline Rock  
13-15 November 2007
Manchester, United Kingdom 

This workshop is the second in a series dealing with geosphere stability for various host rocks types (i.e. crystalline rocks, argillaceous media and evaporites). An important objective of the overall IGSC "geosphere stability" initiative is to ensure the views of the broader scientific community inform the understanding of geosphere stability in radioactive waste management.

Third AMIGO Programme Workshop on Approaches and Challenges for the Use of Geological Information in the Safety Case
15-18 April 2008
Nancy, France

The workshop will facilitate the exchange of information and in-depth discussions on the collection and integration of all types of geologic information (e.g. geophysical, hydrogeological, geochemical, structural) in repository siting and design, performance assessment models and the overall safety case for deep disposal of radioactive waste.

IGSC membership

The IGSC is made up of senior technical specialists experienced in the assembling or review of the safety case for deep geological disposal projects. Most members are drawn from waste management agencies, regulatory authorities and research and development institutions. The level of seniority of the IGSC members is such that they can mobilise relevant specialists in their own organisation and, in principle, can make resources available for IGSC initiatives. The IGSC currently has 46 members from 38 organisations in 17 countries.

The annual IGSC plenary meeting is chaired by the IGSC chairman who is elected for a period of three years. The current IGSC chair is Hiroyuki Umeki from the JAEA. The chair, in consultation with a core group of IGSC members, prepares the plenary meeting. The NEA Scientific Secretariat (igsc@oecd.org) helps in the practical organisation and reporting of the IGSC activities, liaises with the relevant groups and individuals and provides expert input with a view to set in practice the decisions made, or to be considered, by the group.

Publications and reports

Post-closure Safety Case for Geological Repositories (2004)
Nature and Purpose

Establishing and Communicating Confidence in the Safety of Deep Geologic Disposal (2002)
Approaches and Arguments

Related links

IGSC core activities

IGSC technical activities

IGSC co-operative activities

IGSC working area (restricted access)

Radioactive Waste Management Committee (RWMC)

E-mail contact: igsc@oecd.org.

Last updated: 17 September 2007