Expert Group on Operational Safety(EGOS)

EGOS deals with the operational safety of geological repositories. Its aims are to share technical, regulatory and stakeholder experience with regard to operational safety, and to identify operational hazards in a repository using experience gained from the operation of nuclear facilities, mines, and other relevant engineering projects from outside the nuclear industry.

Engineered barrier system (EBS)

An engineered barrier system (EBS) represents the man-made, engineered materials placed within a repository, including the waste form, waste canisters, buffer materials, backfill and seals. In a repository, an EBS is part of a multi-barrier system that is supplemented by the natural geological barrier provided by the repository host rock and its surroundings. Repositories for the disposal of radioactive waste generally rely on a multi-barrier system to isolate the waste from the biosphere to create overall system robustness that enhances confidence that the waste will be successfully contained.  

The IGSC's work on engineered barrier systems has centred on a series of workshops intended to improve the understanding of how to successfully design, construct, model and assess the performance of engineered barrier systems for the disposal of long-lived, high-level radioactive waste. A workshop, entitled Engineered Barrier System in the Context of the Entire Safety Case was held in 2002, based on a state-of-the-art report. The first EBS workshop on design requirements and constraints took place in Turku, Finland, in 2003. The second EBS workshop on process issues took place in Las Vegas, United States in September 2004. The third EBS workshop, entitled Integration of EBS in a Safety Case: The Role of Modelling took place in La Coruna, Spain in 2005. A fourth EBS workshop on design confirmation and demonstration was held in Tokyo, Japan from 13-15 September 2006.