Research and analysis

A review of the treatment of criticality in post closure safety assessment of radioactive waste disposal

A basis for the development of an Environment Agency capability for the analysis of the criticality of post closure radioactive waste disposal issues.


A Review of the Treatment of Criticality in Post-Closure Safety Assessment of Radioactive Waste Disposal

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The report presents a review of key post-closure criticality studies undertaken in radioactive waste disposal programmes around the world (including the Waste Isolation Pilot Plant and Yucca Mountain projects in the US, the Konrad repository in Germany, and proposed deep geologic repositories in the UK, Canada, and Sweden), and also examines the treatment of criticality safety in several waste handling and storage facilities. In general, these studies emphasise the need for post-closure criticality to be considered as part of a repository safety case, although most post-closure criticality studies suggest that criticality is a low-probability event with low consequences in terms of overall repository safety.

Published 1 January 1999