NEA Mandates and Structures


Working Group on the Characterisation, the Understanding and the Performance of Argillaceous Rocks as Repository Host Formations (CLAY CLUB)

Chair(s): Bastian GRAUPNER, Switzerland
Secretary:  Gloria KWONG
(gloria.kwong@oecd-nea.org)
Member(s):All NEA member countries*
Russia (Suspended*)
*Russian Federation suspended pursuant to a decision of the OECD Council.
Full participant(s): European Commission
Under the NEA Statute
Observer(s)(International Organisation): International Atomic Energy Agency (IAEA)
By agreement
Date of creation:01 January 1991
End of mandate:31 December 2020

Mandate (Document reference):

  • CLAY CLUB Mandate [NEA/RWM/CLAYCLUB(2002)1]
  • CLAY CLUB Mandate [NEA/RWM/CLAYCLUB(2006)3]
  • Summary Record of the 8th Meeting of the IGSC [NEA/RWM/IGSC(2006)5]
  • Summary Record of the 11th Meeting of the IGSC [NEA/RWM/IGSC(2009)7]
  • Summary Record of the 12th meeting of the IGSC [NEA/RWM/IGSC(2010)8]
  • CLAY CLUB Mandate [NEA/RWM/CLAYCLUB(2009)1/PROV]
  • CLAY CLUB Mandate [NEA/RWM/CLAYCLUB(2010)3/PROV]
  • CLAY CLUB Mandate [NEA/RWM/CLAYCLUB(2014)3/PROV]
  • Extension of the CLAY CLUB Mandate [NEA/RWM/IGSC(2014)5/PROV]
  • Extension of the CLAY CLUB Mandate [NEA/RWM/IGSC(2016)5/PROV]
  • CLAY CLUB Mandate [NEA/RWM/CLAYCLUB(2016)3]
  • Extension of the CLAY CLUB Mandate [NEA/RWM/CLAYCLUB(2019)1/FINAL]

Mandate (Document extract):

Extract from document NEA/RWM/CLAYCLUB(2019)1/FINAL

Mandate

[...]

Objectives

The Clay Club promotes the exchange of information and shared approaches and methods to develop and document an evolving understanding of clay media as a host rock for a repository.

The Clay Club provides advice to the Integration Group for the Safety Case (IGSC) on major and emerging issues related to the understanding of the multi-scale characterisation, numerical model simulation and barrier performance of argillaceous media.  In particular, the Clay Club addresses recommendations, trends and information gaps concerning issues such as:

  • current knowledge regarding the long-term barrier integrity of argillaceous rocks as relevant to establishing a deep geological repository safety case on time frames of one million years;
  • the development of best international practice with respect to multi-disciplinary laboratory, borehole and in situ characterisation of argillaceous sediments necessary to understand far-field phenomena governing repository evolution, behaviour and long-term performance;
  • a refinement of the understanding of repository-induced effects in argillaceous rocks during excavation, operation and post-closure phases;
  • the application of self-analogues, which at formation scale, provide direct up-scaled formation‑specific properties and evidence of past argillaceous groundwater system stability and resilience to external perturbations;
  • performance assessment, including development of integrated conceptual geosphere models, predictive numerical simulation and abstraction and, traceability of related data and information;
  • links and potential knowledge transfer between the understanding of clay as a host material and its use in engineered barrier systems for deep geological repositories;
  • relevant progress in research and development on argillaceous sediments in other fields or industries, such as oil and gas exploration (performance of cap rocks, unconventional shale oil , shale gas) and CO2 sequestration (performance of enclosing clay barriers).