Description
The investigations carried out to characterise the repository site, both prior to and during repository construction and operation.
Category
Categorisation as a Feature, Event and/or Process.
Features
are physical components of the disposal system and environment being assessed. Examples include waste packaging, backfill, surface soils. Features typically interact with one another via processes and in some cases events.Events
are dynamic interactions among features that occur over time periods that are short compared to the safety assessment timeframe such as a gas explosion or meteorite impact.- "Processes" are issues or dynamic interactions among features that generally occur over a significant proportion of the safety assessment timeframe and may occur over the whole of this timeframe. Events and processes may be coupled to one another (i.e. may influence one another).
The classification of a FEP as an event or process depends upon the assessment context, because the classification is undertaken with reference to an assessment timeframe. In this generic IFEP List, many IFEPs are classified as both Events and Processes; users will need to decide which of these classifications is relevant to their context and its timeframes.
- Process
Relevance to Performance and Safety
The “Relevance to Performance and Safety” field contains an explanation of how the IFEP might influence the performance and safety of the disposal system under consideration through its impact on the evolution of the repository system and on the release, migration and/or uptake of repository-derived contaminants.
These activities establish baseline conditions and provide site-specific data for the post-closure safety assessment. The extent of site investigation affects the degree of uncertainty associated with the assessment. Investigation boreholes could be conduits for groundwater flow if not correctly sealed and so need to be sealed appropriately.
2000 List
A reference to the related FEP(s) within the 2000 NEA IFEP List.
Related References
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IAEA (), Disposal of Radioactive Waste, Specific Safety Requirements No. SSR-5, International Atomic Energy Agency, Vienna, ISBN 978–92–0–103010–8, http://www-pub.iaea.org/MTCD/publications/PDF/Pub1449_web.pdf
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Nuclear Decommissioning Authority (NDA) (), Geological Disposal: Overview of international siting processes, https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/456820/Overview_of_international_siting_processes_September_2013.pdf, August 2013
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NEA (), Engineered Barrier System (EBS): Design Requirements and Constraints, NEA No. 4548, Nuclear Energy Agency/Organisation for Economic Cooperation and Development, ISBN 92-64-02068-3, https://www.oecd-nea.org/rwm/reports/2004/nea4548-ebs.pdf