Welcome to the NEA FEP Database!
Background and objective
The NEA FEP Database is an electronic tool which supports national programmes for radioactive waste management (RWM) in the identification, classification and screening of features, events and processes (FEPs). These are used when defining relevant scenarios for safety assessment for deep geological repositories (DGRs). The NEA FEP Database is composed of two parts:
- International FEP (IFEP) List – a comprehensive and structured generic list of factors relevant to the assessment of the long-term safety of DGRs, developed by the NEA Integration Group for the Safety Case (IGSC). IGSC intends to maintain and update the IFEP List in future to reflect developments in safety assessment and its methodologies.
- Project-specific FEP (PFEP) Lists – collections of FEP lists, with references, that have been developed by radioactive waste management organisations (RWMOs) as part of their safety assessments. Every FEP of each RWMO's PFEP List can be mapped to one or more of the international FEPs within the database to demonstrate consistency. Organisations who would like to add their list to the database should contact the NEA Secretariat.
In 2018 NEA launched a new web-based platform for the NEA FEP Database, accessible from this webpage. This new database has been designed to allow full version control of all lists and is intended to provide a home for all releases of the NEA IFEP List in future. Moreover, it has been designed to allow RWMOs to upload and manage their own PFEP Lists.
Past versions of the NEA FEP Database were implemented in a commercial standalone software package with custom tools to assist in locating and examining FEPs and related information. Several versions were produced, and included FEP lists from different types of repository project for different kinds of waste. The versions that were publically released are:
- NEA2000 – This included the first public version of the IFEP List (i.e. IFEP List 1.0) and 8 PFEP Lists (download); and
- NEA2006 – This included the IFEP List 1.0 and 11 PFEP Lists (download).
History of the IGSC FEP Project
The NEA has carried out activities related to the compilation and use of lists and databases of FEPs in safety and performance assessment studies of radioactive waste disposal facilities since the early 1990s. In 2000 NEA released a report containing the first public version of the IFEP List (i.e. IFEP List 1.0) together with the NEA2000 software. This was superseded by the NEA2006 software six years later.
In 2010, NEA launched a questionnaire on “the use of FEPs in performance assessment studies and the scope for related NEA Integration Group for Safety Group (IGSC) activities”. In light of the questionnaire findings, the NEA supported a revision of the FEP Project, intended to ensure it remained useful and relevant to the work of member states. This revision included the:
- review and update of the IFEP List 1.0; and
- implementation of an associated web-based database (i.e. this site).
In 2015, NEA published an interim IFEP List (referred to as IFEP List 2.0). This internal list included:
- information on the relevance of each FEP to the “performance and safety of the disposal system”; and
- references and/or web-links to provide further information about each FEP.
The IFEP List 2.0 was developed in light of a review of various project-specific lists and databases, undertaken in 2012, and the resulting revisions to the structure of the IFEP List were subsequently approved by the NEA IGSC group.
In 2019, the interim IFEP List produced in 2015 was finalised and published as the IFEP List 3.0. This is the first version IFEP List to be hosted in the new web-based database (login).
Salt Club FEP Database
The Salt Club FEP Database is a comprehensive catalogue of generic features, events, and processes (FEPs) that are potentially important for the post-closure performance of a repository for high-level radioactive waste (HLW) and spent nuclear fuel (SNF) in salt (halite) host rock. The generic salt repository FEPs include consideration of relevant FEPs from a number of United States, Dutch, German, and international FEP lists and should be a suitable starting point for any repository programme in salt host rock.
The salt FEP catalogue and database employ a FEP classification matrix approach that is based on the concept that a FEP is typically a process or event acting upon or within a feature. The FEP matrix provides a two-dimensional structure consisting of a Features/Components axis that defines the “rows” and a Processes/Events axis that defines the “columns” of the matrix. The design of the FEP classification matrix is consistent with repository performance assessment – the Features/Components axis is organized vertically to generally correspond to the direction of potential radionuclide migration (from the waste to the biosphere) and the Processes/Events axis is designed to represent the common two-way couplings between thermal processes and other processes (such as thermal-mechanical or thermal-hydrologic processes). Related FEPs can be easily identified – related FEPs will typically be grouped in a single matrix cell or aligned along a common row (Feature/Component) or column (Process/Event).
The online Salt FEP Database can be downloaded from www.saltfep.org. It contains the FEP matrix, the FEPs, and the associated processes for each FEP. It provides a starting point to create and document site-specific individual FEPs. Furthermore, the FEP matrix is connected to the Salt Knowledge Archive (SKA), a database of about 20,000 references and documents representing the historical knowledge on radioactive disposal in salt. This work is the result of an ongoing collaboration between researchers in the United States, the Netherlands, and Germany, and supports the NEA Salt Club Mandate.
- 2000 - Features, Events and Processes (FEPs) for the Geologic Disposal of Radioactive Waste (i.e. International FEP List 1.0)
- 2013 - Updating the NEA International FEP List – An Integration Group for the Safety Case (IGSC) Technical Note
- Technical Note 1: Identification and Review of Recent Project-specific FEP Lists
- Technical Note 2: Proposed Revisions to the NEA International FEP List
- 2015 - International FEP List 2.0 (not publicly issued)
- 2019 - International FEP List 3.0 (download)