FORGE: Fate of Repository Gases
Long-term radioactive waste management usually considers final disposal in a deep geological repository. This includes an engineered barrier system working in conjunction with the surrounding host rocks to minimise migration of radioactivity. As the repository system evolves, gases may be produced, such as hydrogen from the corrosion of metals and from the radiolysis of water, and radon from the radioactive decay of some of the waste. If present, biodegradable wastes can also produce carbon dioxide and methane. Understanding how these gases move in a repository setting is a topic identified for further study. The FORGE project, which ran from February 2009 to September 2013, studied key gas migration issues in repository performance assessment.
Overview
Project Dates: 01/02/2009 – 30/09/2013
Project Status: Finished
Project Website: https://www.bgs.ac.uk/forge/
The underground disposal of radioactive wastes involves a series of barriers, both natural and engineered, between the waste and the surface. Achieving this multi-barrier concept is fundamental to all disposal programmes and the long-term containment of radioactive waste.
Understanding gas generation and migration is crucial in the quantitative assessment of repositories and was the focus of this international, multi-disciplinary project.
FORGE contributors included radioactive waste management organisations, regulators and academia who together researched the following key areas:
- Impact of gas migration on repository infrastructure and engineering performance.
- New models to describe the mechanisms and processes governing gas, water and radionuclide movement in repository components.
- New insights into the engineered barrier systems (EBS) properties, engineered disturbed zone (EDZ) behaviour, far-field interactions, gas generation and up-scaling.
Objective
The FORGE project consisted of five work packages:
- Treatment of gas in performance assessment.
- Gas generation.
- Engineered barrier and seals.
- Disturbed host rock formations.
- Undisturbed host rock formations.
Further detail about these work packages is provided below.
Work package 1 – Treatment of gas in performance assessment
The ultimate aim of WP1 was to make recommendations for, and propose an updated treatment of, gas issues in relation to long-term safety assessments, based on the integrated findings from the project.
Work package 2 – Gas generation
WP2 examined the rate of hydrogen production in order to provide information in support of repository performance assessment. Specific issues that were studied included:
- Consumption of hydrogen by reaction with radiolytic products such as hydroxide ions.
- Inhibition of corrosion by the products of radiolysis.
- Effect of water chemistry (e.g. the influence of carbonate reactions with hydroxide ions).
- Effect of clay/cement barriers on hydrogen production and its migration through samples under irradiation.
Work package 3 – Engineered barrier and seals
The aim of WP3 was to investigate gas migration processes and the consequences of gas migration in the Engineered Barrier System of repositories.
Work package 4 – Disturbed host rock formations
WP4 aimed to develop understanding of the roles of the stress tensor, the stress path and associated mechanical deformation in determining permeability changes affecting the sealing efficiency of the host rock. Laboratory, field and numerical simulations were undertaken.
Work package 5 – Undisturbed host rock formations
The main objectives of WP5 were to:
- Establish the conditions under which different gas migration processes are dominant.
- Identify how those processes can be modelled and determine the values of the main parameters.
- Measure the parameters that may have an impact on the long-term safety as a consequence of enhanced radionuclide transport through the host rock.
Funding Bodies
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European Union
Funding Bodies
FORGE received funding from the European Union’s Seventh Framework Euratom Programme under grant agreement number 230357. The total cost was 11.63 million Euros, with the EU contributing 5.99 million Euros. Further information is available at https://cordis.europa.eu/project/rcn/89382_en.html.
Related Documents
Description: 6 reports: D1.1 - Draft report on definition of benchmark studies on repository scale numerical simulations of gas migration D1.2 - Summary of gas generation and migration current state-of-the-art D1.3 - Progress report on benchmark studies on repository-scale numerical simulations of gas migration D1.4 - Preliminary report on benchmark studies on repository-scale numerical simulations of gas migration D1.5 - Synthesis report: updated treatment of gas generation and migration in performance assessment D1.6 - Final report(s) on repository-scale numerical simulations of gas migration
Last updated: September 20, 2018
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Description: 5 reports: D2.1 - State of the art, experiment specifications and validation of experimental devices D2.2 - Preliminary results of hydrogen evolution rate and transport properties in compacted bentonite D2.3 - Preliminary interpretation of experimental and modelling results D2.4 - Experimental progress D2.5 - Synthesis of experimental processes governing gas generation
Last updated: September 20, 2018
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Description: 36 reports (no reports for D3.23 or D3.28) D3.10 2nd progress report D3.11 Report on conceptual design of the gas cell HLW experiment D3.12-R Small scale experimental results and modelling D3.13 Measurements of gas entry pressure D3.14 Detailed description on gas migration tests in concrete D3.15 Results of the tests on bentonite (part 1) D3.16 Results of the tests on concrete (part 2) D3.17 Report on conceptual design of the gas borehole experiment D3.18 Report on experimental borehole results D3.19 Technical notes on bentonite and concrete experiments D3.1-R State of the art report on gas transport through interfaces D3.2 Description of proposed in situ experimental set-ups (within URL) D3.20 Report on bentonite laboratory experiments D3.21 Models of in situ gas flow experiments D3.22 Internal reports on numerical experiments D3.24 Poromechanical effects and water displacement (bentonite/argillite interface) D3.25 Experimental results and interpretation (in terms of processes) D3.26 Results and interpretation of the gas migration tests (concrete) D3.27 Results of the tests on bentonite (part 2) D3.29 Final report on models of gas migration in bentonite D3.3 Description of proposed laboratory experimental set-ups and procedures (bentonite, interface and concrete) D3.30 Final report: test results / numerical parameter sets (bentonite/argillite interface) D3.31 Final modelling results and progress in gas transport modelling D3.32 Report on gas movement in EBS system under repository scale D3.33 Final report on key gas migration processes in compact buffer D3.34 Final report on sand/bentonite laboratory experiments D3.35 Experimental results with argillite-bentonite tubes D3.36 Final report on interface laboratory experiments D3.37 Final report on carbon dioxide reactions with repository cement D3.38-R Experiments and modelling on the behaviour of EBS D3.4 Description of proposed initial numerical codes and conceptual model D3.5 Progress report D3.6 Results of the tests on concrete (part 1) D3.7 Experimental results with aluminium-plexiglass tubes (bentonite/argillite interface) D3.8 Final report on LML experimental results D3.9 Interim report on interface laboratory test state
Last updated: September 20, 2018
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Description: 24 reports D4.1 Description of laboratory experimental set-ups (argillaceous and crystalline formations ) D4.10 Progress report on HG-A experimental activities D4.11 Progress report - field installation and initial tests (Boom Clay) D4.12 Progress report - definition of constitutive laws and initial simulations D4.13 Progress report - definition of constitutive laws and initial simulations D4.14 Progress report - baseline hydraulic measurements D4.15-R Preliminary report - numerical simulation of lab and field tests D4.16-R Final report - field results and conceptual understanding of self-sealing processes (Opalinus Clay) D4.17 Experimental results and interpretation (process understanding of argillaceous and crystalline formations) D4.18 Experimental results and interpretation (process understanding within URL) D4.19 Final report - field results and conceptual understanding of self-sealing processes (Boom Clay) D4.2 Description of proposed in situ experimental set-ups (within URLs) D4.20 Final report - field results and conceptual understanding of gas flow (crystalline rock) D4.21 Final report - modelling gas and water flow in plastic and indurated clay EDZā??s D4.22 Final report - numerical simulation of lab and field tests (disturbed host rock formations) D4.23 Final report - Simulation results (HG-A) D4.24-R Experiments and modelling of EDZ behaviour in argillaceous and crystalline rocks D4.3 Report - compilation of existing data (Mont Terri) D4.4 Progress report - design of Boom Clay in situ test D4.5 Description of initial numerical codes and conceptual model D4.6 Progress report - review of Opalinus and Boom Clay parameters D4.7 Progress report - simulation of initial designs D4.8 Report - HM modelling of HG-A micro tunnel D4.9 Progress report - field installation and rock characterisation
Last updated: September 20, 2018
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Description: 18 reports (no report for D5.10) D5.1 Detailed description of experimental set-up and procedure for gas-driven radionuclide transport D5.11 Opalinus clay gas induced fractures D5.12-R Report on modelling and interpretation of in situ gas migration experiments D5.13 HM modelling of PGZ and parameters studies D5.14 Opalinus clay 2-phase flow parameters D5.15 Modelling and interpretation of in situ gas migration experiments D5.16 Key gas migration processes in the Callovo-Oxfordian argilite D5.17 Experimental results and interpretation (in terms of processes) (laboratory and in situ gas migration experiments) D5.18 Experimental comparisons and inverse method application (undisturbed host rock formations) D5.19-R Experiments and modelling of gas migration processes in undisturbed rocks D5.2 Design, installation and compilation of existing data for the HG-C experiment at Mont Terri D5.3 Description of laboratory gas transport experimental set-ups and procedures D5.4 Design and installation of the PGZ1 experiment at Bure D5.5 Description of initial numerical codes and conceptual model (undisturbed host rocks) D5.6 Progress report on HG-C experiment at Mont Terri D5.7 Progress report: Experimental geometry and preliminary results (laboratory gas transport experiments) D5.8 Results and interpretation of gas-driven radionuclide transport in Boom Clay D5.9 Progress report on PGZ1 experiment at Bure
Last updated: September 20, 2018
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Description: 5 reports D0.2-R Performance indicators for progress monitoring D0.5-R PUDKA D0.7-R Report on the scientific achievements of FORGE D0.8-R Overview report summarising key outcomes from the project D0.9 Workshop proceedings and/or book(s) published on principal outcomes of the project
Last updated: September 20, 2018
FORGE: The role of stress history on the flow of fluids through fractures
Last updated: September 20, 2018
FORGE: Observations of heterogeneous pore pressure distributions in clay-rich materials
Last updated: September 20, 2018
FORGE: Explatory Data Analysis of the Large Scale Gas Injection Test (Lasgit)
Last updated: September 20, 2018
IGD-TP Members Participating in the Activity
ANDRA
Member of Executive Group
Agence Nationale pour la gestion des déchets radioactifs
The French National Radioactive Waste Management Agency.
Contact: Stephan Schumacher Send message
British Geological Survey (BGS)
Contact: Enquiries Send message
Centre National de la Recherche Scientifique (CNRS)
The National Center for Scientific Research, France
Contact: Michel Cathelineau Send message
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT)
Center for Energy, Environmental and Technological Research
Contact: Tiziana Missana Send message
Le Commissariat à l’énergie atomique et aux énergies alternatives (CEA)
French Alternative Energies and Atomic Energy Commission
Contact: Catherine Rabbe Send message
Gesellschaft für Anlagen- und Reaktorsicherheit mbH (GRS)
Contact: Tilmann Rothfuchs Send message
Contact: Klaus Fischer-Appelt Send message
Lithuanian Energy Institute (LEI)
Contact: Povilas Poškas Send message
Nagra
Member of Executive Group
Nationale Genossenschaft für die Lagerung radioaktiver Abfälle
Contact: Irina Gaus Send message
Posiva Oy
Member of Executive Group
Nuclear Waste Management Expert
Contact: Tiina Jalonen Send message
SCK – CEN
Belgian Nuclear Research Centre
Contact: Christophe Bruggeman Send message
SKB International AB
Contact: Erik Thurner Send message
Nuclear Research Institute Rez (UJV)
Contact: Vaclava Havlova Send message
Related Research Areas
Key Topic 1: Post-closure Safety Case
Research in this area aims to consider how consistent safety cases across the different waste management programmes can be developed, how safety assessment concepts and models can be developed and refined, and how sensitivity and uncertainty treatment can be improved.