NERC and NWS will fund a single multidisciplinary consortium of researchers to undertake fundamental underpinning research to advance our understanding of the potential effects that the introduction of a geological disposal facility (GDF) for radioactive waste might have on lower strength sedimentary host rock. This includes detailed conceptualisation of the geology and groundwater.
The UK has generated electricity from nuclear power for more than 60 years. The use of nuclear power is set to persist and scale up as part of the UK government’s plan to reach net zero carbon emissions by 2050.
To deliver these objectives there is a need to have a clear plan for disposal of the generated nuclear waste in a way that is not harmful to the environment or human health.
The development of a GDF is central to government policy regarding the management of higher activity radioactive wastes. Lower strength sedimentary rocks (LSSR) are one of the geological environments identified as being potentially suitable for providing a host rock in which to construct a GDF.
However, there are fundamental knowledge gaps around the geology, hydrogeology and controls on subsurface properties of these systems. These knowledge gaps must be addressed to provide the fundamental underpinning knowledge required to inform future decisions around disposal of radioactive waste as the UK transitions to low carbon energy production.
This programme is independent from other NWS investments and work concerning siting of a GDF within the UK. The programme will support fundamental research into the geology and dynamics of how fluids flow through generalised lower-strength sedimentary rock environments. Research conducted and funded by this programme will not form the appraisal of any specific site. Geographic selection of the site, or sites, of any field research necessary to meet the programme objectives, will need to be fully justified within the proposal.
It is expected that through the partnership between NERC and NWS, the funded consortium will work with other current NWS investments including via the Research Support Office. An appropriate budget should be included within the proposal to facilitate this interaction and other relevant activities (see ‘Engagement with NWS Research Support Office’ heading).
Applications to this funding opportunity must address all 3 of the programme objectives. The proposal should demonstrate integration of new research in geology, hydrogeology, radionuclide behaviour and predictive modelling to understand and predict how potential lower strength sedimentary host rock environments might be impacted by the introduction of a GDF.
1. Geological isolation challenges
The effective, long-term isolation of radioactive waste requires a detailed knowledge of the physico-chemical nature of the larger rock volume within which the waste will be disposed. In turn, understanding the resilience of the rock volume to perturbations in stress, chemistry and temperature, induced by subsurface engineering, waste emplacement, and GDF closure, is key.
This objective focuses on characterisation and conceptualisation of geological complexity and heterogeneity at multiple length and time scales within LSSR, addressing key knowledge gaps such as:
- uncertainty around the likely variation in values describing the magnitude and evolution of flow and geomechanical properties in LSSR formations in the UK (for example with varying lithology and heterogeneity)
- identification of key processes (for example, advection versus diffusion in the matrix, or transmissivity in the undisturbed far field or excavated damage zone) and how they will evolve over the lifetime of the repository
Research questions could include (but are not limited to):
- characterisation of the lithological heterogeneity of LSSRs on all scales:
- what is the level of heterogeneity at scales from pore to geological formation?
- what influences this heterogeneity?
- what effect does this heterogeneity have on the resulting range in physical properties, specifically multiphase flow and mechanical?
- quantifying existing natural fracture paths and those produced by the engineered structure:
- what is the nature of pre-existing fracture networks on all scales within LSSRs?
- what type of fracture damage would be introduced around the engineered structure?
- what intrinsic properties, or burial or diagenetic history of LSSRs determines the propensity for fracture damage?
- evolution of critical flow pathways:
- how does the host rock or fracture networks respond to existing or changing environmental conditions (thermal, chemical, biological) over timescales commensurate with the lifetime of the GDF?
- what are the parameters that increase the probability of self-sealing?
2. Contaminant pathways
The aim of this objective is to develop a mechanistic understanding of retention and, or transport within LSSR, for:
- priority radionuclides (for example, uranium and uranium series radionuclides)
- longer lived fission products and non-radioactive contaminants (for example, organics and heavy metals)
To increase understanding of the key controls on radionuclide transport processes in evolving LSSR systems, this objective will focus on radionuclide and, or contaminant behaviour, including:
- radionuclide interactions within relevant LSSR host rock materials
- groundwater geochemistry
Research questions could include (but are not limited to):
- what is the long-term fate of radionuclides within realistic LSSR systems considering spatial and temporal heterogeneity and scale (for example, pressure, temperature, gases, salinity, redox, pH and microbiology)
- what are the biogeochemical characteristics which make an LSSR system a robust barrier to radionuclide release, and how do these differ between LSSRs?
- what are the impacts of the critical transport and dispersion pathways in LSSR systems (for example, advective vs diffusive) on radionuclide behaviour and how do we improve predictability of these controls?
- what is the potential impact of the chemical and, or engineered disturbed zone on radionuclide transport in LSSR systems (for example, in altering or affecting mobility of higher-solubility radionuclides)?
- how do we optimise experimental systems to provide the advanced mechanistic understanding required to underpin and feed into robust predictive modelling?
3. Mathematical modelling
The outputs of objectives 1 and 2 will form the baseline information which will be used to develop system level mathematical models of the key sedimentary systems.
The mathematical models and codes developed as part of this research programme will focus on several key processes that would affect the environment surrounding a GDF, for example:
- thermal effects from waste and damage caused by excavation process
- fracture network development and consequent effects on water and gas flow and transport properties
- deformation processes within the host rock and the overall geochemical evolution of the system
Additionally, this objective will seek to take new approaches to computational modelling by:
- building fully coupled thermo-hydro-mechanical-chemical (THMC) computational codes that can accurately model the growth and coalescence of fracture networks in LSSR
- validating these codes against relevant analytical solutions and, or data generated in objectives 1 and 2 of the programme.
Funding and duration
We will fund a single consortium to address all 3 objectives of the programme.
The full economic cost of the project can be up to £5 million. We will fund 80% of the full economic cost for eligible UK organisations following full economic costing principles such that the total cost to NERC and NWS is no greater than £4 million. The exceptions to this are:
- directly incurred equipment (over £10,000) is funded at 50%
- eligible international co-investigator costs (under the IIASA or Norway agreement) are funded at 100% for eligible direct costs. This can be a maximum of 30% of the total full economic cost of the grant, which for this funding opportunity equates to a maximum of £1.2 million. Find out about collaborating with researchers in Norway and refer to the guidance for how to enter international costs in the Joint electronic Submission (Je-S) form.
||Funding from NERC or NWS if successful
|UK projects costs
||£3312.5k (100% full economic cost)
||£2650k (at 80%)
||300k (100% full economic cost)
||£150k (at 50%)
|IIASA or Norway co-investigator costs (up to £1.2 for this funding opportunity)
||£1200k (at 100% direct costs
Projects must start no later than 2 October 2023 and last no longer than 48 months.
In addition to achieving the scientific objectives, the project is also required to undertake the following activities that must be planned for in the project proposal.
Engagement with NWS Research Support Office (RSO)
The RSO is a dedicated office funded through NWS to support the delivery of independent evidence-based research to underpin the implementation of a UK GDF.
The funded consortium will be expected to engage with the NWS RSO community. This will link the consortium with the wider GDF programme, including the community of more than 100 researchers, academics and NWS subject matter experts working on GDF related research in the UK.
The funded consortium will be expected to attend the RSO annual conference. Travel and subsistence costs for this should be included in the submitted project budget along with any other foreseeable costs that might be needed to support engagement with the NWS RSO.
While this research programme sits apart from and is independent to wider work on siting a GDF within the UK, the knowledge and evidence generated here will be critical to informing decisions and policies pertaining to storage of radioactive waste in the UK. Additionally, it will inform wider discussions surrounding use of the subsurface as part of the green energy transition.
We expect that the proposal will detail:
- any proposed mechanisms or strategies to encourage impact from and uptake of the data, evidence and understanding generated as part of the programme
- stakeholder engagement plans to ensure this impact and uptake
Diversity within consortia
NERC and NWS encourage the construction of diverse project teams, including early career researchers.
Proposals should demonstrate how early career researchers will be supported to develop their careers, to ensure capacity building for the future in this field. In addition, project plans should ensure they address how diversity and inclusion best practise will be considered and embedded in all project activities undertaken.
The assessment panel will consider the diversity of the project team along with due consideration for championing diversity and inclusion within project plans, as part of the assessment criteria (see ‘How we will assess your application’).
British Geological Survey (BGS) core store
Principal investigators wishing to access geological samples at the BGS core store within the National Geological Repository need to contact the core store at least 2 months prior to submitting a proposal.
They will need to discuss the proposed work and receive confirmation that the services required can be provided within the timeframe of the grant.
The core store will provide a letter of support to:
- state that the access required is feasible within the timeframe of the grant
- outline the estimated number of lab days required, and the associated costs, which should be included in the grant, under the directly incurred other costs heading
UK Geoenergy Observatories (UKGEOS)
NERC’s new UKGEOS facility has 2 sites in Glasgow and Cheshire with networks of instrumented boreholes that are available for use in research into subsurface fluid flow and other experiments, supported by core and other materials collected during construction. Please visit the UKGEOS website for more details on how to further discuss your research idea and to request access to the facility and related samples.
Other services and facilities
Principal investigators wishing to use other NERC services and facilities will need to contact the relevant facility at least 2 months prior to submitting a proposal.
They will need to discuss the proposed work and receive confirmation that they can provide the services required within the timeframe of the grant.
The facility will then provide a technical assessment that includes the calculated cost of providing the service.
NERC services and facilities must be costed within the limits of the proposal. The technical assessment must be submitted as part of the Je-S form, as detailed in the ‘How to apply’ section.
Find out about NERC facilities that require a technical assessment, excluding high performance computing, ship-time or marine equipment and the large research facilities at Harwell as these services have their own policies for access and costing.
The NERC data policy must be adhered to, and an outline data management plan produced as part of proposal development.
NERC will pay the data centre directly on behalf of the programme for archival and curation services. Applicants should ensure that they request sufficient resource to cover preparation of data for archiving by the research team.