Description
Any type of mining or excavation activity carried out in the vicinity of the repository. These activities include conventional blasting and excavation practices, strip mining and solution mining.
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.
- Event
- Process
Comments
The “Comments” field, when present, contains any additional explanation of the IFEP, beyond that implicit in the FEP's description and provided in the “Relevance to Performance and Safety” field. This additional explanation may include, where appropriate, the IFEPs characteristics, the circumstances under which it might be relevant and its relationship to other (especially similar) IFEPs.
Mining may be undertaken with or without knowledge of the repository (FEP 1.4.4).
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.
Mining and other underground activities are relevant to repository performance and safety because, depending upon the distance between these activities and the repository, they will perturb the geosphere around the repository and the repository itself. There may be a combination of mechanical, hydrogeological and chemical perturbations. If sufficiently close to the repository, the integrity of the repository could be compromised; in the most extreme case mining or other underground activities could intrude into the repository, either accidentally or deliberately. Excavated openings could potentially form pathways by which radionuclides or other contaminants originating in a repository could migrate all or part of the way from the repository to the biosphere. The latter situation would arise if the openings connect other kinds of pathway, as when an excavation connects a repository to a naturally transmissive fracture zone. The openings could act as pathways during their excavation or when operations are undertaken in them, or at some time afterwards if they are imperfectly sealed. Potentially, the stresses in the rocks surrounding a repository and in the repository itself could be affected by mining and other underground activities. Consequences could include the creation of fractures, or the dilation or contraction of existing fractures. These fractures could form pathways for the migration of radionuclides or other contaminants. Roof collapses in underground excavations could produce collapse columns that might become pathways by which radionuclides and / or other contaminants could be transported. Mining and other underground activities may involve introducing and / or removing water or other fluid from the subsurface (e.g. groundwater may be extracted during mine drainage operations, or gas that has been previously stored in salt caverns may be removed). These activities could influence groundwater heads and hence groundwater flow rates and directions in and / or around a repository. Groundwater chemistry could also be influenced, with possible impacts on the migration or retardation of radionuclides and / or other contaminants that might originate in a repository. For example, underground redox conditions may be influenced by mining, with consequent impacts on the evolution of barriers.
2000 List
A reference to the related FEP(s) within the 2000 NEA IFEP List.
Related References
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NEA (), Future Human Actions at Disposal Sites, A Report of the NEA Working Group on Assessment of Future Human Actions at Radioactive Waste Disposal Sites, Nuclear Energy Agency/Organisation for Economic Cooperation and Development, ISBN 92-64-14372-6, https://www.oecd-nea.org/rwm/reports/1995/nea6431-human-actions.pdf
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SKB (), Handling of future human actions in the safety assessment SR-PSU, SKB Technical Report TR-14-08, Svensk Kärnbränslehantering AB, http://www.skb.com/publication/2478137/TR-14-08.pdf