Corporate report

Regulatory scrutiny and engagement for geological disposal: annual report 2022 to 2023

Updated 22 October 2024

Foreword

The Environment Agency is the independent environmental regulator for the nuclear industry in England. Our activities are guided by our plan ‘EA2025 creating a better place’. This plan acts as our compass, enabling us and others to chart a course towards a healthier, greener and more prosperous country.

Our EA2025 plan sets out 3 main goals:

• a nation resilient to climate change
• healthy air, land and water
• green growth and a sustainable future

Our regulation of disposals of radioactive waste, including radioactive discharges to air and water, and disposal of solid waste to land, aligns with these goals. It helps ensure that these facilities are designed and operated in ways which minimise waste and protect the environment.

The Office for Nuclear Regulation (ONR) is the UK’s independent nuclear regulator for safety, security and safeguards at licensed nuclear sites in the UK. Our mission is to protect society by securing safe nuclear operations.

ONR has the legal authority to regulate nuclear safety, nuclear security and conventional health and safety at the 35 licensed nuclear sites in Great Britain. We also regulate the safety of transporting radioactive materials and work closely with the International Atomic Energy Agency (IAEA) to ensure that the UK’s safeguarding obligations are met.

This is a joint Environment Agency and ONR publication that summarises our work relating to the geological disposal of radioactive waste during 2022 to 2023. As regulators for these wastes, we are working together to make sure that any future geological disposal facility (GDF) will meet the high standards for environmental protection, safety, safeguards and security that the law requires, and the public expects.

We have established agreements with Nuclear Waste Services (NWS), the organisation responsible for developing a GDF, to provide regulatory advice and to scrutinise its work. We are engaging with NWS early, before regulation starts, so that when a site is identified, NWS already clearly understands what it needs to do as part of the regulatory process. We also liaise with NWS to make sure that it gives the right advice to waste producers about packaging radioactive waste for future disposal at a GDF. This helps NWS understand what it needs to do to meet applicable legal requirements for environmental protection, safety, radioactive materials transport, safeguards and security. It also helps us better understand NWS’s work and lets us prepare in advance for any permit or licence applications we might receive from NWS, so that we can respond promptly and knowledgeably.

We have no regulatory role in selecting potential sites for a GDF. However, we support communities that are considering hosting a GDF on matters relating to our respective areas of regulation.

We have set out our regulatory expectations for geological disposal, covering our respective remits. The Environment Agency has issued its Guidance on Requirements for Authorisation (GRA)^{[footnote 1]}. ONR has issued a technical assessment guide on geological disposal^{[footnote 2]}, which it updated in March 2023, and will draw on relevant aspects of the Safety Assessment Principles for Nuclear Facilities (SAPs)^{[footnote 3]}, the Security Assessment Principles for the Civil Nuclear Industry (SyAPs)^{[footnote 4]} and the Construction (Design and Management) Regulations 2015.

Throughout this document ‘we’ refers to both the Environment Agency and ONR. Where comment is made on matters specific to one regulator, ‘we (Environment Agency)’ or ‘we (ONR)’ is used.

As independent regulators, we are committed to making our work open and transparent. This report will help us to continue to do this.

Further information on the Environment Agency’s role in regulating a GDF can be found at Regulating the geological disposal of radioactive waste: environmental protection and further information on ONR’s engagement on the GDF can be found on the geological disposal section of the ONR website.

Executive summary

This report summarises the work that the Environment Agency and the Office for Nuclear Regulation (ONR) carried out to scrutinise Nuclear Waste Services’ (NWS’s) work and our associated interactions with the public from April 2022 to March 2023.

A site has not yet been selected to host a geological disposal facility (GDF). However, NWS is holding ongoing discussions with several potential host communities. NWS has started evaluation work in these areas, with the aim of selecting up to 2 sites to carry out detailed intrusive investigations. We continue to develop our relationships with the GDF community partnerships that have formed to date, and to provide information on how we would regulate a GDF.

In late March 2023, NWS informed us of changes in its target operating model (the way it plans to operate), which will result in changes to the management arrangements to the GDF Programme. We will be monitoring the implications of these changes on the GDF Programme and the main programme milestones, to ensure that there is adequate governance of the programme and that permitting and licensing requirements are fully considered.

We provided regulatory advice to NWS on a number of topics, including:

• its management arrangements for holding an intrusive investigation permit for potential GDF sites and its proposed commercial delivery strategy and operating model
• feedback on its framework for strategic decision-making about GDF siting
• visiting NWS’s borehole sealing trials at Rosemanowes Quarry in Cornwall, concluding that management arrangements were broadly fit-for-purpose and identifying as good practice the use of a decision tree for the crew to consult if events do not go to plan
• reviewing its updated principles that guide and inform the design of the GDF, concluding that they are consistent with international principles
• feedback on its Visualisation of System Information (ViSI) system, concluding that this could potentially provide a useful resource for documenting the safety claims that form the backbone of the environmental safety case (ESC) and the supporting safety arguments and evidence
• raising concerns about inconsistent and out-of-date planning assumptions on the GDF first waste emplacement dates that underpin some waste management strategies on the NDA estate
• feedback on its interim position paper on options for disposing of plutonium and on its post-closure criticality safety case assessment

Our current level of regulatory advice and scrutiny is based on the need for NWS to have suitable technical and organisational arrangements in place when it applies for an intrusive investigation permit. NWS is making good progress towards these goals. However, while changes to its target operating model and reorganisation of its GDF Programme are ongoing, we cannot determine whether its plans are adequate. NWS does have time to put suitable arrangements in place.

NWS will need to support its permit and licence applications with suitable claims, arguments and evidence that are underpinned by its technical programme of work. Ahead of its decision to select up to 2 sites for intrusive investigations, NWS’s design and safety case work continues to be generic. We encourage NWS to ensure that its technical underpinning for site-specific aspects of its work is adequate, in particular for settings such as the Mercia Mudstone Group, the candidate host rock in the Cumberland communities, for which no good analogue underground research facilities exist.

To ensure that we are ready to assess any applications from NWS, we continued our preparatory work to develop the regulatory guidance necessary, and to share and learn from other GDF programmes overseas, for example, in France, Canada and Switzerland.

1. Introduction

Radioactive waste has been, and continues to be, produced from the UK’s historic and current nuclear power, research and defence programmes, as well as from industries, hospitals and universities that use radioactive material.

There is currently no available route in the UK to dispose of higher activity waste (HAW), the most radioactive category of waste, so it is stored on existing nuclear sites until a solution can be found.

UK government policy for the long-term management of HAW in England is described in the 2018 policy document^{[footnote 5]}. This sets out the framework for managing HAW through geological disposal, focusing on how a geological disposal facility (GDF) would be implemented in England. Similarly, the Welsh Government has adopted a policy of supporting geological disposal for the long-term management of HAW^{[footnote 6]}.

Scottish Government policy does not support geological disposal. Rather, its policy is for the long-term management of HAW in near-surface facilities that are located as near to the site where the waste is produced as possible.

The Nuclear Decommissioning Authority (NDA) is responsible for implementing government policy on the long-term management of radioactive waste. Nuclear Waste Services (NWS), which is part of the NDA Group, is responsible for developing a GDF. NWS was created in January 2022 by the integration of Radioactive Waste Management (RWM) - a subsidiary of NDA that was responsible for developing a GDF, Low Level Waste Repository Ltd (LLWR) - also an NDA subsidiary, and the NDA’s Integrated Waste Management (IWMP) Programme.

The Environment Agency and ONR are responsible for making sure that any future GDF in England or (for ONR only) Wales meets the high standards necessary to protect people and the environment when it is being developed, while it is operating, and after it has closed.

We will be responsible for granting the necessary environmental permits and nuclear site licence, and for our respective regulatory roles of environmental protection, safety, security, radioactive materials transport and safeguards. Regulatory control of a GDF is likely to be required for at least 150 years.

Our regulatory partner Natural Resources Wales (NRW) has similar environmental protection responsibilities for Wales, and we keep them aware of matters arising and important outcomes from our work.

We are engaging with NWS now to make sure that any future applications to develop a GDF take account of all permitting and licensing requirements. We also want to make sure that NWS gives the right advice to waste producers, so that radioactive waste packaged at its sites is suitable for future disposal, can be safely stored in current stores, and can be safely transported to a future disposal site.

Discussions at this early stage will help us prepare in advance for any permit or licence application we might receive from NWS, so that we can respond promptly and knowledgeably.

In addition, it ensures that the waste producers and NWS fully understand our regulatory expectations and can provide adequate documentation to support any future applications.

At this stage, before considering issuing permits or a licence, we are providing regulatory advice rather than making regulatory decisions.

In 2022 to 2023, the Environment Agency and ONR implemented a new regulatory engagement structure that better reflects the GDF Programme, which we developed with NWS during 2021 to 2022^{[footnote 7]}. As we embedded this structure into our ways of working, our engagement during the earlier parts of 2022 to 2023 focused more on the planning and organisational development rather than the more technical aspects of the GDF Programme. By the end of 2022 to 2023, the new engagement process was fully implemented and working effectively in most areas.

2. Support to the siting process

We have no regulatory role in selecting potential sites for a geological disposal facility (GDF). However, we:

• offer our support to communities that are considering hosting a GDF
• advise on matters relating to our respective areas of regulation

As of April 2023, 4 GDF community partnerships have formed in England: the Allerdale, Mid Copeland, South Copeland and Theddlethorpe GDF Community Partnerships. The potential GDF host rock of interest in all 4 areas is in the inshore area, that is the underground part of the facility which would be located deep below the seabed up to the outer limit of UK territorial waters at around 22 km offshore. NWS believes that new communities may enter the siting process in 2023 to 2024.

Our regular discussions with NWS about its plans for community partnerships and proposals for new working groups are helping us support community discussions. Our communications and engagement plan sets out our objectives, stakeholders and activities. These activities include publishing information and infographics, and materials to use at public exhibitions as well as engaging with groups and community partnership members to explain our role. The information includes: 

• a short animation to explain the regulators’ role in geological disposal available on YouTube
• an overview of the regulatory processes that the Environment Agency and ONR will apply to the development, operation and closure of a GDF in England
• information pages on GOV.UK and the Office for Nuclear Regulation websites

Mid Copeland, South Copeland and Allerdale GDF Community Partnerships

We did not attend any community events organised in these areas during 2022 to 2023. Instead, our engagement focused on building relationships with the Cumbria (Cumberland as of 1 April 2023) community partnerships, including hosting a webinar in June 2022 on how we would regulate a GDF, to which we invited members of all 3 Cumbria community partnerships. We are seeking further opportunities to engage with members of the partnerships and need better links to the chairs and partnership members.

We welcomed the opportunity to be involved in NWS’s Cumberland market research survey on geological disposal in February 2023 and to run an article in the Mid Copeland Voice in March 2023 which contained information about the role of the regulators. We are developing our local engagement plans for each partnership. They are informed by market research, local conversations, questions and concerns raised at local meetings and our own engagements.

Theddlethorpe GDF Community Partnership

The Theddlethorpe GDF Community Partnership was formally announced on 30 June 2022. We offered our support to the Chair and partnership members. We suggested holding a meeting explaining how we would regulate a geological disposal facility and offered to support community partnership events, but did not attend any events during 2022 to 2023. We are developing our local engagement plan which includes regulator events and public and stakeholder communications to help raise awareness of our role. An article appeared in Theddlethorpe Voice in February 2023 which contained information about the role of the regulators.

Wider stakeholder engagement on geological disposal

In May and October 2022, the Environment Agency held its bi-annual ‘meet the regulators’ engagement forum for stakeholders in Cumbria to provide an opportunity for discussion and questions about geological disposal.

The Office for Nuclear Regulation’s NGO Forum meets twice each year. The meetings provide an opportunity to discuss and engage with members of the NGO community on a range of issues, including geological disposal. During the reporting period, the Forum met once in November 2022. Minutes from the meeting are available on the ONR website.

We responded to some general enquiries from the public and NGOs about how we would regulate geological disposal.

We (Environment Agency) met with the Committee on Radioactive Waste Management (CoRWM) Sub-group 3 (Planning and Regulation) in November 2022 to discuss CoRWM draft papers on GDF costs and an inshore GDF, and regulatory views on the need for an underground research facility (URL). We also observed at several virtual CoRWM open plenary sessions. ONR met with CoRWM in November 2022 to discuss the same papers and provide views on the requirement for a URL.

Working with NWS

We continue to exchange information about our communications and engagement activities at monthly meetings with NWS’s community engagement team. We work with NWS to consider how best to share information about regulation with community partnerships and any future working groups that may emerge. We have also asked to receive updates from NWS on its corporate communications on geological disposal, national stakeholder engagement, and work with CoRWM.

In order to focus and develop our engagement, we (ONR) have appointed an NWS corporate inspector to bring together our work on the geological disposal facility (GDF), Low Level Waste Repository (LLWR) and the Integrated Waste Management Programme (IWMP).

4. Regulatory preparations

Engaging with Nuclear Waste Services (NWS) on geological disposal at an early stage helps us prepare for any environmental permit or nuclear site licence application that we might receive, so that we can respond promptly to what will be a first of a kind activity.

While regulating geological disposal is similar to ongoing regulatory activities, it also has some significant differences and it may be necessary to enhance regulatory capabilities in some areas at certain times.

We anticipate that regulated activities will continue for around 150 years from the start of construction of a geological disposal facility (GDF), during its operation and through to its final closure. This means that regulators will need to maintain their capability over extended periods during design, construction and operation.

It should be recognised that regulatory responsibilities and requirements may change and evolve during the design, construction, operation, closure and post-closure periods of a GDF. There could also be unexpected changes in government policy on waste disposition routes. We give advice and scrutiny based on the latest knowledge, directions and legal requirements. We maintain and enhance our capabilities to meet our responsibilities in regulating geological disposal. This includes engagement with other regulators and international programmes relevant to radioactive waste disposal.

Permitting and guidance

We (Environment Agency) are developing guidance for the developer on how we will apply our staged regulation process to a GDF throughout its lifecycle, as summarised in Regulating geological disposal: an overview. Our guidance for the initial stage (surface-based intrusive investigation, which will comprise the drilling of deep site investigation boreholes) is feeding into parallel work to produce templates for the environmental permit and application form, along with associated guidance for GDF intrusive investigation activities. Associated guidance includes guidelines on ‘how to apply’ for an intrusive investigation permit.

An intrusive investigation permit application from the developer will need to be accompanied by an initial site evaluation (ISE) and our (Environment Agency) guidance will incorporate details from our draft ISE guidance document^{[footnote 8]}. An ISE will need to:

• provide largely qualitative views on the feasibility of developing a GDF at a candidate site
• explain how intrusive site investigation work would inform any future environmental safety case if a candidate site were to be selected for development of a GDF
• demonstrate that intrusive investigation work would not compromise the integrity of a candidate site to the unacceptable detriment of the environmental safety case
• inform a regulatory decision to allow intrusive investigation work to start

NWS gave us a presentation on its plans for site characterisation and borehole drilling at a workshop in February 2023. This provided useful background to inform the development of our permit template and guidance development.

Due to the links between our guidance on staged regulation and the permitting templates, we have aligned the timescales for producing these products. We plan to share our updated draft guidance with NWS and other stakeholders in 2023 to 2024. 

We (Environment Agency) are also updating our Guidance on Requirements for Authorisation (GRA) of geological disposal facilities on land for solid radioactive waste^{[footnote 1]}. We intend to produce consolidated guidance covering both near-surface and geological disposal facilities. We aim to publish a draft updated GRA document for external consultation in early 2024.

We (ONR) are currently revising our guidance for nuclear site licence applicants, which will include specific information related to the GDF. The current version is available on our website, on Licensing nuclear installations.

We (ONR) are working with government on the necessary modifications to the legal framework to allow for licensing of a GDF. This work will be completed well in advance of any application for a nuclear site licence. It is only after a preferred site is identified with a willing host community that the developer will apply for a licence and other relevant planning consent. Before construction can begin, the developer will need to hold appropriate environmental permits and a nuclear site licence.

Capability building

We (Environment Agency) have begun enhancing our existing capability framework to ensure that we can provide GDF regulation over the coming decades.

We have continued to host internal training seminars on topics of relevance to geological disposal, including in 2022 to 2023:

• the geology of the Mercia Mudstone Group and its potential suitability as a GDF host rock
• radioactive waste management and disposal in Germany
• HAW disposability considerations

We also prepared and provided role-specific training for staff who started working on our GDF projects during 2022 to 2023.

We (Environment Agency) continued our quarterly engagement with the Marine Management Organisation (MMO) throughout 2022 to 2023. The aim of this engagement is to develop a mutual understanding of each organisation’s regulatory roles and responsibilities associated with the development of a GDF in the inshore area. Topics for discussion included protection of groundwater under the seabed in the inshore area and MMO’s requirements for licensing borehole investigations. We agreed to work together to produce information materials to explain to wider stakeholders our roles in regulating the inshore environment. We also attended an MMO training session on the application of marine plans and policies for Environment Agency staff.

We (ONR) continue to build capability and resilience within both our frontline regulatory staff and specialist assessors by planned rotation of staff, targeted recruitment of specialists and engagement internationally. We have arrangements in place to monitor capability and resilience using our Professional Lead group in ONR covering all specialisms.

International engagement

During 2022 to 2023, both the Environment Agency and ONR engaged with other regulators and international programmes relevant to geological disposal, both in person and virtually. This engagement provided us with valuable information and learning from international organisations, GDF developers and regulators from countries that are in various stages of GDF siting and development.

The Environment Agency participated in the following events:

The 3rd joint Nuclear Energy Agency (NEA) Integration Group for the Safety Case (IGSC)/Forum for Stakeholder Confidence (FSC) workshop ‘Building confidence in the face of uncertainty: the role of the safety case’. Held in Bern, this world café-styled event included representatives of regional Swiss and German community partnerships who gave a good insight into the success factors regarding the Swiss siting process. We also visited the Grimsel Test Site, an underground research laboratory (URL) in granitic rock.

The 2022 Clay Conference in Nancy, France. This conference provided an excellent overview of international research and the main challenges supporting safety case development for geological disposal facilities located in clay host rocks and/or using engineered clay as a backfill solution. We also visited the Bure URL, which is in clay, and the associated Technological Exhibition Facility.

NEA cross-party working groups exploring the different aspects of trust, including input to the Working Group on Public Communication of Nuclear Regulatory Organisations’ (WGPC) forthcoming guidance on ‘the characteristics of a trusted regulator’, developing a joint case study with ONR on good practice.

The European Joint Programme on Radioactive Waste Management (Eurad) uncertainties management (UMAN) virtual seminar on ‘Uncertainties related to human aspects’, which investigated views from the varied participants on a variety of difficult/contentious issues around geological disposal.

The NEA IGSC annual meeting. This provided updates from various international radioactive waste disposal programmes and projects, plus a focused session from near-surface and GDF programmes about when and how reasonable confidence is achieved when developing a safety case.

The NEA FSC’s annual conference held in Dessel, Belgium. This was combined with a Belgian national workshop on ‘Fostering stakeholder involvement across generations - participation after site selection’. This workshop focused on the success factors 20 years after the Mol-Dessel Partnership formation, which has successfully delivered a near-surface repository in the region and state-of-the-art visitor centre.

Virtual engagement with the Canadian nuclear safety regulator (CNSC) to share our respective approach to repository oversight activities and aspects of interest in each regulator’s GDF programme.

We (ONR) target our international engagement with the International Atomic Energy Agency (IAEA), fully utilising our position as Chair of the IAEA Waste Safety Standards Committee (WASSC) to build our networks with other regulators. We also attended a variety of virtual seminars on all aspects of radioactive waste management and disposal, including those hosted by the NEA and IAEA.

ONR on behalf of the UK government took the lead role in drafting the UK national report to the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management at the Seventh Review Meeting of the Contracting Parties in July 2022. We reported on UK progress on disposal and attended all other national presentations, including from those countries where progress with construction of a GDF is more advanced. At the review meeting, we gave a joint presentation with the Environment Agency and an update on UK progress on GDF work. We also attended sessions by other contracting parties who are progressing with their own GDFs.

5. Organisational capability and development

The developer or operator of a GDF should foster and nurture a positive organisational culture (promoting safety, security and environmental compliance) at all times. It should also have a suitable management system, organisational structure, and enough resources to provide essential functions (GRA Requirement 4^{[footnote 1]}, LC 17 and 36).

We (Environment Agency) need to be confident that Nuclear Waste Services (NWS) can comply with environmental permit requirements before we issue environmental permits for borehole investigations at potential sites.

NWS must also continue to develop its organisational capability and management systems, so that it is capable of holding and implementing the necessary requirements of environmental permits and a nuclear site licence to construct and operate a GDF.

We (ONR) recognise that NWS is not currently close to the point of licensing a GDF, and its organisation is being developed for the next tranche of work. Our current focus is on providing advice on the management arrangements and processes needed to support a capable organisation in line with the requirements of our licence conditions.

We continued with a programme of engagement with NWS on the organisational development for its GDF Programme, although the frequency of this engagement was impacted by continued organisational change within NWS over the year.

Organisational development ‘keep in touch’ meetings resumed in 2022 to 2023, supported by ad-hoc technical engagements on the following elements of NWS’s organisational arrangements:

• management arrangements, including the scope of and progress with the management system gap analysis that WSP is carrying out on behalf of NWS
• capability and competency, with focus on NWS’s organisational capabilities to support intrusive site investigation
• the proposed commercial delivery and operating model to deliver the main packages of work for Tranche 3 of the GDF Programme

We (Environment Agency) provided written advice to NWS on these topics, which included the following observations:

• NWS’s approach to identify its preferred arrangements appears reasonable.
• We note the proposed model appears to be a complex mix of alliance, partnering and direct contracting. We consider this could bring NWS challenges in terms of exercising effective oversight and control of activities.
• we see governance and assurance activities around implementation and ongoing delivery of the GDF Programme as key organisational capabilities. These are aspects we will look to explore in greater detail as part of future scrutiny engagement with NWS.

In order to assess its commercial delivery arrangements, we asked NWS for additional details of the development and implementation of arrangements for managing client-partner interactions, including definitions of roles and responsibilities, intelligent customer and associated assurance arrangements.

We (ONR) provided advice on the development of the intelligent customer capability. We advised NWS that it needs to develop its capability to safely carry out construction activities as the proposed deep borehole investigations will likely constitute notifiable construction work as defined in the Construction (Design and Management) Regulations 2015 (CDM Regulations). We will continue to work with NWS to ensure appropriate regulatory advice and oversight is provided regarding the development of the process for initial design of the GDF.

NWS conducted a planned borehole sealing trial at Rosemanowes Quarry in Cornwall (see the section on ‘Borehole sealing’), and the Environment Agency attended to observe arrangements, including aspects of management and control of contractors. We concluded that the arrangements were broadly fit-for-purpose and provided some observations for NWS to consider in its future development of its organisational arrangements.

Over the past year, we also held meetings with NWS to ensure that we maintain sight of the broader direction of its organisational development, and the alignment of arrangements for the GDF Programme within it.

The NWS reorganisation, and re-baselining of the intrusive investigation and design and safety case business cases, will have implications for our organisational development scrutiny work (principally in relation to areas of focus and schedule). We will be looking to clarify and address these implications with NWS in 2023 to 2024.

6. Preparing for intrusive investigations

As specified in our staged regulation process for geological disposal, NWS will need to apply to the Environment Agency for an environmental permit to carry out the drilling of deep site investigation boreholes. The applications must take full account of our environmental permitting requirements (GRA section 5^{[footnote 1]}). Based on current planning assumptions, we anticipate receiving applications for up to 2 sites in early 2027, and we are currently developing our guidance on staged regulation and the permitting templates (see the section on ‘Regulatory preparations’).

NWS will also require a Development Consent Order (DCO) to begin the intrusive investigations. The Environment Agency is a statutory consultee in this process.

Advice on major permissions

We (Environment Agency) are providing advice to NWS on our requirements for the intrusive investigation permit application and the supporting initial site evaluation (ISE). NWS transferred the list of queries on environmental permitting, jointly prepared by NWS and the Environment Agency in 2021 to 2022, into the regulatory engagement plan for this component of the GDF Programme and the regulatory deliverables tracker. We engaged on these topics in 2022 to 2023 through regular ‘keep in touch’ and topic-specific meetings.

We gave advice to NWS on how we will assess application of best available techniques (BAT) and optimisation in the context of the intrusive investigation permit. We aim to adapt our approach to enable effective regulation of the different stages and categories of GDF intrusive investigation activities. We clarified that the intrusive investigation permit is a radioactive substances activity permit. If intrusive investigations involve a groundwater activity, then we would incorporate groundwater protection conditions in the same permit. Other activities, for example, water discharge and waste disposal, would be authorised under separate permits.

We explained to NWS our consultation approach for permit applications and provided a list of organisations we may consult as part of the process. We also outlined other legislation we must consider when assessing applications for radioactive substances activities permits. We confirmed that an assessment under the Transboundary Radioactive Contamination (England) Direction 2020 is unlikely to apply at the intrusive investigation stage.

Our flood risk experts provided information to NWS on the extent of the flood risks and the nature of flood defence systems along the coast of Theddlethorpe in Lincolnshire. We informed NWS that we would review and comment on the flood risk assessments for the proposed GDF via the DCO process in our role as a statutory consultee.

We last provided feedback on NWS’s permissions schedule in 2018^{[footnote 9]}. Since we provided this advice, NWS has revised its GDF Programme. It confirmed that its permissions schedule has been superseded by other deliverables led by its Major Permissions Team. We wish to understand how NWS is considering recommendations from our earlier interactions in our ongoing engagement on this topic to make sure that it maintains a complete and appropriate understanding of the permissions it needs to have in place and any interactions between them. 

The Office for Nuclear Regulation (ONR) is not the safety regulator for the drilling of the deep site investigation boreholes and has advised that NWS should engage with the Health and Safety Executive (HSE). If early engagement with HSE is not possible, ONR considers it likely that NWS will have to formally notify HSE of the intended construction work under the CDM Regulations. HSE will then consider the appropriate regulatory approach. ONR will review NWS’s approach to this construction work at an appropriate time to inform our assessment of any future nuclear site licence application.

Borehole sealing

In the ISE that accompanies a permit application for the drilling of deep site investigation boreholes, we (Environment Agency) expect NWS to explain how the borehole can be subsequently sealed in a way that provides appropriate environmental protection^{[footnote 8]}. NWS has a research and development (R&D) programme on borehole sealing, which includes using laboratory scale and field trials to demonstrate that it can adequately seal site investigation boreholes before it begins drilling them. NWS’s objective for this work is to demonstrate that it has approaches, equipment and a toolkit of techniques and solutions that can be applied in sealing any borehole in a range of settings.

Following a field trial using existing shallow redundant boreholes drilled in lower strength sedimentary rock on the Harwell nuclear licensed site in 2020 to 2021, NWS identified 2 deeper boreholes drilled in higher strength rock at the borehole test facility at Rosemanowes Quarry in Cornwall that it used in a second field trial in September 2022. We (Environment Agency) provided feedback on the design of the field trial and NWS’s approach to implementing it. We confirmed our acceptance of the revised approach to the field trials and that the proposed toolbox approach could be acceptable in an ISE, subject to its content meeting our expectations. We provided 3 recommendations regarding future work:

• Future borehole sealing research, if carried out, should be informed by knowledge and experience gained from the earlier phases.
• Any future borehole sealing research should identify and address any particular challenges for the geologies being considered in search areas to inform the relevant parts of the ISE and pre-application engagement.
• NWS should develop a clear set of objectives and measures of success for any future work ahead of developing further laboratory and field-based activities. We consider that discussion on this for the Rosemanowes field trials has been particularly helpful in achieving the current position.

We (Environment Agency) visited the field trials at Rosemanowes to gain confidence that:

• the system developed by NWS and its contractors to seal boreholes can be deployed successfully at depth
• the borehole sealing work is being developed sufficiently to address the range of conditions and challenges that may be presented during the delivery of a GDF
• NWS contractor management arrangements are appropriate, and the site is managed safely to protect people and the environment
• NWS demonstrates sufficient intelligent customer capability
• the work is adequately controlled and supported by arrangements

We confirmed that the arrangements we observed during the planning of the field trial and our visit were broadly fit for purpose (see the section on ‘Organisational capability and development’). We identified the use of a decision tree for the crew to consult if events do not go to plan as good practice.

NWS completed technical work associated with phase 4 of its borehole sealing project in 2022 to 2023 and we will engage on the outputs of the project, in particular the developments of claims, arguments and evidence on borehole sealing, in 2023 to 2024.

Site evaluation

NWS started its site evaluation and comparative assessment work programme in 2022 to 2023. It shared with us the processes that it will follow to identify and evaluate potential GDF sites. The site evaluation process considers safety, environment, transport, security and safeguards, engineering feasibility and value for money in each potential area.

Regulators are independent of the evaluation process, but will provide advice on matters relevant to our respective regulatory remits.

NWS is developing a site descriptive model (SDM) for each area that will provide the data required to underpin the evaluation topics, for example, geological, hydrogeological and geotechnical data, and identify information gaps and uncertainties that it will need to address in its developing safety cases. We (Environment Agency) will engage further with NWS as it develops the SDMs for each area, starting with early versions based on desk-based information during 2023 to 2024. We also wish to review its processes and procedures for managing data flow between the SDM and models underpinning the site evaluation ahead of the intrusive investigation permit application. 

NWS carried out a marine seismic survey of the geology in the inshore region off the Copeland coast during summer 2022. It also purchased legacy seismic data for the inshore areas off the Copeland, Allerdale and Theddlethorpe coasts. NWS is currently processing and interpreting these data sets, and the outputs will inform the developing SDMs. Final outputs from this work are not yet available.

Site investigation programme development

We (Environment Agency) expect NWS to have appropriate plans and procedures in place to carry out the site investigation and characterisation work needed to implement geological disposal, and to inform the safety cases and GDF design and construction (GRA Requirement 11^{[footnote 1]}). At this stage, we want to make sure that NWS’s plans and actions for future site investigations are consistent with our permit requirements and would not compromise the integrity of potential GDF sites.

NWS is developing its plans for site investigation activities. It provided us (Environment Agency) with further information on these activities in early 2022^{[footnote 7]}, including:

• its developing site characterisation programme and plans for integrating the results from non-intrusive site investigations (for example, seismic surveys) and intrusive site investigations (for example, borehole drilling)
• challenges associated with borehole drilling in the inshore environment
• management and governance arrangements for site characterisation data

We reviewed this information in 2023 to 2024 to support our ongoing engagement with NWS on its programme of work to prepare permit applications for intrusive investigations, with particular reference to technical challenges associated with planning and carrying out an intrusive investigation in the inshore area.

NWS presented its plans for intrusive investigations to the Environment Agency and ONR in February 2023. This provided useful background information for the Environment Agency in developing the intrusive investigation permit template and guidance. We anticipate further engagement on NWS’s developing site characterisation plans in 2023 to 2024. We have requested further information on well design, for example, on drilling mud composition and use of chemical breakers, which we understand will be included in the basis of well design reports that we expect to receive in early 2023 to 2024.

We (Environment Agency) have requested engagement in early 2023 to 2024 about NWS’s plans for further investigation and characterisation to underpin future safety cases, including any plans for an underground research laboratory. This is also a topic of interest to the Committee on Radioactive Waste Management (CoRWM) (see the section on ‘Wider stakeholder engagement on geological disposal’).

7. GDF development

NWS’s applications to develop a GDF must take full account of our environmental permitting requirements (GRA section 5^{[footnote 1]}) and the duties placed on operators of a licensed nuclear site (nuclear safety, security, safeguards, radioactive materials transport, and conventional health and safety).

NWS’s understanding and interpretation of the full range of relevant legislation and guidance should be consistent with our expectations (GRA Part 2^{[footnote 1]}, Licensing Nuclear Installations). It should also be aware of new and emerging regulations.

Any application for an environmental permit relating to a proposed disposal of solid radioactive waste must be supported by a suitable environmental safety case (ESC)^{[footnote 1]}. Similarly, any application for a nuclear site licence to construct and operate a GDF will need to be supported by adequate demonstrations of safety and security^{[footnote 11]}.

We want to establish a clear and common understanding with NWS of the requirements of permit and licence applications to make sure that any future applications take full account of our regulatory requirements. We engaged with NWS on its design and safety case development at ‘keep in touch’ meetings throughout 2022 to 2023 and at several topic-specific meetings and workshops.

GDF design and system requirements

NWS presented its plans for the staged development of the GDF design and safety cases during Tranche 3 to regulators at a workshop in February 2023. We expect to receive several design and safety case development documents for scrutiny in early 2023 to 2024.

We reviewed NWS’s draft 2022 design principles, which are the safety, environmental, security and safeguards principles that will guide and inform the design of the GDF and update the 2014 Radioactive Waste Management (RWM) version. Both regulators provided written feedback to NWS, concluding that it was a useful document that was consistent with international principles, but that it would benefit from information detailing where the principles sit in NWS’s document hierarchy and how they will be used. The Environment Agency advised that the links between NWS’s design principles and sustainability principles needed to be more closely acknowledged.

The Environment Agency also emphasised the need to make clear the distinction between ‘optimisation’ as defined by the International Commission on Radiological Protection (ICRP), that is optimisation of radiological protection (doses should all be kept as low as reasonably achievable, taking into account economic and societal factors), and the colloquial meaning of ‘optimisation’, taking into account the joint regulatory position previously agreed with RWM in 2018^{[footnote 11]}.

Safety case development

NWS is developing its Visualisation of System Information (ViSI) system to document the claims, arguments and evidence (CAE) underpinning its ESC. NWS gave the Environment Agency access to a trial version of ViSI that contained draft CAE branches for operational environmental safety and criticality. We focused our review on how ViSI can support the development of an ESC for a GDF and did not review the technical content of the branches. We provided feedback to NWS in July 2022, concluding that ViSI could potentially provide a useful resource for documenting the safety claims that form the backbone of the ESC and the supporting safety arguments and evidence. We found it intuitive to navigate through the 2 CAE branches in the trial version and follow links to the evidence and underpinning references. We provided feedback to NWS on issues that it should consider when developing ViSI. We advised NWS that we wish to continue our engagement on ViSI as the system is developed and populated.

We have several open Regulatory Issues (RIs) and Regulatory Observations (ROs) in this area. NWS provided us with verbal updates on its progress against GDF_RO_014 (operational environmental safety case) and GDF_RI_015 (fire safety assessment) in late 2022 to 2023. Regulators will review outstanding actions when we receive formal responses (expected early 2023 to 2024).

NWS presented to regulators its approach to developing a list of internal and external hazards that could affect the GDF during the operational and post-closure phases at a meeting in March 2023. NWS confirmed that this work included reviewing both the Nuclear Energy Agency’s (NEA) international list of features, events and processes (FEPs) and recent international safety cases to develop a longer list of FEPs to inform the development of the ESC. A screened list will be issued to regulators for scrutiny in early 2023 to 2024.

The Environment Agency advised NWS to ensure that its terminology relating to safety case development is used consistently and in line with the expectations of both regulators.

8. Waste management

Waste producers are responsible for appropriately characterising, treating and packaging higher activity waste (HAW) to meet the expected waste acceptance criteria of a GDF. The operator of a GDF (along with the consignee) will be responsible for making sure that the consigned waste is consistent with the eventual GDF waste acceptance criteria; the design requirements; the environmental safety case; and the operational requirements, including transport and handling (GRA Requirement 13^{[footnote 1]}).

NWS operates its disposability assessment process to reduce risk in the waste conditioning and packaging process, and to make sure that wastes are compatible with the current geological disposal concept and designs. Through this process, NWS provides disposability advice to waste producers and potential waste producers on the packaging of their HAW.

We expect NWS to assess packaging proposals for HAW against clear and consistent published specifications. This is to assure us that HAW is suitably packaged for handling and disposing of in a GDF. We also expect NWS to share good practice in waste packaging to avoid duplication of effort.

We engage with NWS to build confidence that:

• HAW will be packaged in a way that is suitable for transporting to, handling and disposing of, at a GDF in line with the safety case and with no, or minimal, reworking
• HAW will be conditioned to a safe, passive, transportable and disposable form as soon as is reasonably practicable
• NWS’s procedures, guidance, specifications, and limits encompass the full range of wastes destined for geological disposal and are likely to ensure compliance with permit requirements so that they are acceptable for disposal

Disposability assessment

NWS continues to evolve its disposability assessment process. We continue to see more emphasis from NWS on earlier technical discussions to support waste producers in the early stages of considering waste management treatment and storage options, particularly for more technically challenging waste streams. We welcome this collaboration between NWS and the waste producers.

NWS briefed us on its prioritised plan to update all its guidance for waste packaging and we will monitor progress with this in 2023 to 2024.

NWS also works with the Nuclear Decommissioning Authority (NDA) and the waste producers as part of the NDA-led Disposability Risk Management Group. This group was set up to ensure an appropriate balance between competing requirements through the full lifecycle of the waste (from waste retrieval and packaging at sites, through to onsite storage, transport to GDF and operational and post-closure repository performance). This group is considering some test cases and we expect the initial conclusions on these to be shared with regulators for consideration in 2023 to 2024.

We have 2 open Regulatory Issues in this area and we reviewed these with NWS at the end of 2022 to 2023. The first of these is on assessment of innovative packaging proposals and their impact on NWS’s disposal system technical specification and safety case^{[footnote 12]}. The second is on the sensitivity of waste packaging assessments to changes in the GDF design or safety case^{[footnote 13]}. Together, these issues are intended to give us confidence that developments in waste packaging advice to nuclear sites and the GDF concept design and safety assessments are kept in step with one another. We have taken account of NWS developments in both these areas and plan to carry out a scrutiny inspection of relevant arrangements during 2023 to 2024.

Waste package records and assurance

For waste packages and records that have already been produced, NWS continues to develop its approach to assurance through its periodic review process. This is done to maintain confidence in the disposability of these wastes through their interim storage period. It is also an important part of ensuring that previous disposability advice remains consistent with the GDF requirements, design, and safety case as they develop. We are aware of some recent developments in NWS’s periodic review and records assurance processes, including trialling this at Sellafield, and we will be seeking a further update on this in 2023 to 2024.

Disposability of high heat generating waste

High heat generating waste is a category used by NWS for the most hazardous wastes in the inventory for disposal to a GDF. This includes spent fuel from existing and future power stations and high level waste from spent fuel reprocessing. High fissile wastes (plutonium and high enrichment uranium) are also included in this group as they have similar disposal requirements even though they don’t generate significant amounts of heat.

Now that fuel reprocessing has stopped at Sellafield, there is increasing focus on expert technical advice from NWS about the disposability implications of alternative interim storage and potential treatment options for spent fuel. We are aware of progress with this and expect to engage in more detail during 2023 to 2024.

In 2022 to 2023 NWS produced an interim position paper on plutonium disposal options and we held technical meetings with NWS on this and provided feedback. This was based on our review of the post-closure criticality safety case assessment and plans to develop this further. This review informed our formal advice to NDA on its plutonium disposition paper to government. We have started the next phase of engagement with NWS on its development of plutonium packaging options and associated criticality safety modelling and this will continue into 2023 to 2024.

Disposability of low heat generating waste

Low heat generating waste refers to the rest of the waste inventory (that is, the majority by volume that is not high heat generating). NWS has continued to provide disposability advice to sites on relevant packaging proposals for these waste streams. In 2022 to 2023, our engagement with this work was primarily through our site regulation rather than scrutiny of NWS, and is not reported here.

9. NWS’s research, development and demonstration

The developer and operator of a GDF needs to carry out timely research, development and demonstration (RD&D) to inform its activities and ensure it fulfils its obligations, such as demonstrating optimisation to keep doses from radiation as low as reasonably achievable or practicable (ALARA or ALARP).

The developer and operator need to be aware of any scientific developments, both within and outside the UK, which may have a bearing on the environmental safety case for the facility (GRA Requirement 4^{[footnote 1]}).

We expect NWS to have a targeted and prioritised RD&D programme in place, informed by wider national and international research or implementation programmes. NWS will need to identify and address in a timely way those issues that require RD&D to meet our requirements.

NWS should be clear, through its management process, why the RD&D it undertakes is needed and what knowledge gap it will fill.

Our engagement with NWS over the past few years has been focused on assuring ourselves that it is appropriately managing its RD&D activities through by reviewing its Science and Technology (S&T) Plan and Programme, and engaging on several specific technical areas. In 2021 to 2022, we raised concerns that significant cuts to the RD&D budget due to GDF Programme budgetary constraints would increase programme risk as a result of a reduction in information needed to substantiate future safety case claims and arguments ^{[footnote 7]}. We also noted a resultant impact on supply chain capability. We requested the following information from NWS:

• annual ‘frozen’ versions of the S&T programme change control summary and long-range graphics that provide an overview of significant changes and progress
• details of the process NWS used to prioritise the activities in its S&T Programme and the impacts of the exercise on the GDF Programme and underpinning RD&D activities

NWS informed us in 2022 to 2023 that it was reorganising its S&T activities into themes. We, therefore, deferred engagement on how NWS prioritises its RD&D programme and management of risks until this process was complete. We will engage further during 2023 to 2024. We also encouraged NWS to publish its RD&D programme regularly, like many other international waste management organisations (for example, SKB in Sweden).

Outputs of NWS’s RD&D will support many aspects of the GDF Programme on which we currently engage, in particular its design and safety case, and site evaluation and characterisation. NWS informed us that relevant RD&D deliverables will be included in the GDF Programme deliverables tracker it is developing, for example, its borehole sealing research (see the section on ‘Geological disposal programme’).

We (Environment Agency) attended the NWS Research Support Office (RSO) annual conference in January 2023 and gave a presentation on the potential extent of societal change over the lifetime of a GDF, using historical examples. The RSO is a collaboration between the University of Manchester and the University of Sheffield to harness UK university capabilities to help support radioactive waste management solutions. The conference allowed researchers to present on research that will support the development of the GDF and underpin the safety cases.

We also attended an RSO workshop on developing a research proposal titled ‘From land to sea: characterising and understanding risks from radioactive contaminant sinks in an evolving marine environment’ in March 2023.

10. Summary

In 2021 to 2022, Radioactive Waste Management (RWM) transitioned into Nuclear Waste Services (NWS). The organisational change associated with this transition is ongoing and NWS aims to become a single legal entity by 31 March 2024. We are monitoring the implementation and management of these changes across NWS, including implications on the GDF Programme.

We implemented a new regulatory engagement structure on the GDF Programme in 2022 to 2023. Because of this, our engagement during the earlier parts of the year focused on the planning and organisational development rather than the more technical aspects of the GDF Programme. By the end of 2022 to 2023, the new engagement process was fully implemented and working effectively in most areas. However, in late March 2023, NWS informed us of changes in its target operating model, which will result in changes to GDF Programme management and governance, and a further reorganisation of the GDF Programme. We will be monitoring the implications of these changes on the GDF Programme and any resultant effects on important programme milestones and the efficiency of regulatory engagement.

We provided advice on a number of topics, including:

• making sure that NDA and waste producers are aware of current assumptions on GDF first waste emplacement dates and making sure that their decommissioning plans and export schedules are consistent with the GDF Programme
• NWS’s developing management arrangements for GDF development and the proposed commercial delivery and operating model
• NWS’s management arrangements for the Rosemanowes borehole sealing trial
• GDF design principles
• NWS’s Visualisation of System Information (ViSI) system to document the claims, arguments and evidence underpinning its environmental safety case
• plutonium disposal options and the post-closure criticality safety case assessment

We acknowledge that NWS has made progress on outstanding Regulatory Observations and Regulatory Issues. However, during the reporting period we did not fully close any out. One Regulatory Observation on building confidence in data and modelling remains open. In addition, 5 Regulatory Issues on assessment of innovative packaging proposals, disposability assessments and endorsements sensitive to change, characterisation and assessment of the non-radioactive component of waste in the inventory for disposal, operational environmental safety assessment, and approach to fire safety assessment remain open.

We (Environment Agency) provided advice to NWS on its requirements for the intrusive investigation permit application. We are also developing our guidance on the application of staged regulation of a GDF throughout its lifecycle and templates for the environmental permit and application form, along with associated guidance for GDF intrusive investigation activities. We continue to engage with NWS as it develops its plans for intrusive investigations.

We have offered advice on how we would regulate a GDF to communities in all the areas in which community partnerships have formed, but did not attend any community events in 2022 to 2023. However, we have engaged with local stakeholders via other channels.

Annex A: List of Regulatory Issues and Observations

Regulatory Issue	Title	Status
GDF_RI_001	Leadership and governance	Closed
GDF_RI_002	Organisational capability	Closed
GDF_RI_003	Control and assurance	Closed
GDF_RI_004	Organisational learning	Closed
GDF_RI_005	Assessment of innovative packaging proposals	Open
GDF_RI_006	Resolution of periodic review findings	Closed
GDF_RI_007	Assurance of packaging assessments and advice	Closed
GDF_RI_008	Board governance of important areas of risk/performance	Closed
GDF_RI_009	Corporate Health, Safety, Security, Environment and Quality (HSSEQ) structure	Closed
GDF_RI_010	Disposability assessments and endorsements sensitive to changes	Open
GDF_RI_011	Waste package records	Closed
GDF_RI_012	Workforce capability plan	Closed
GDF_RI_013	Characterisation and assessment of the non-radioactive component of waste in the inventory for disposal	Open
GDF_RI_014	Operational environmental safety assessment	Open
GDF_RI_015	Approach to fire safety assessment	Open

Regulatory Observation	Title	Status
GDF_RO_001	Protection against non-radiological hazards	Closed
GDF_RO_002	Optimisation	Closed
GDF_RO_003	Lessons from the Fukushima disaster	Closed
GDF_RO_004	Defining waste package fissile limits for disposal	Closed
GDF_RO_005	Lessons from the Waste Isolation Pilot Plant (WIPP) incident	Closed
GDF_RO_006	Building confidence in data and modelling	Open
GDF_RO_007	Auditable evidence in support of an environmental safety case (ESC)	Closed
GDF_RO_008	Defining waste package fissile levels	Closed

References

1. Environment Agency and Northern Ireland Environment Agency, February 2009. Geological disposal facilities on land for solid radioactive wastes: Guidance on Requirements for Authorisation. [Accessed 5 October 2023]. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰

2. ONR, March 2023. Technical Assessment Guide. Geological disposal. Revision 1.3. [Accessed 5 October 2023]. ↩

3. ONR, January 2020. Safety Assessment Principles for Nuclear Facilities ONR CM9 Ref 2019/367414. 2014 Edition, Revision 1. [Accessed 5 October 2023]. ↩

4. ONR, March 2022. Security Assessment Principles for the Civil Nuclear Industry. 2022 issue, version 1. [Accessed 5 October 2023]. ↩

5. Department for Business, Energy & Industrial Strategy (December 2018) Implementing geological disposal – working with communities. An updated framework for the long-term management of higher activity radioactive waste.  [Accessed 5 October 2023]. ↩

6.  Welsh Government (2015) Welsh Government Policy on the Management and Disposal of Higher Activity Radioactive Waste  [Accessed 9 October 2023]. ↩

7. Environment Agency. Guidance on information required in support of an application for an environmental permit for intrusive investigation work. Draft 2.0, 7 February 2014. ↩ ↩² ↩³

8. Environment Agency and ONR. Regulatory scrutiny and engagement for geological disposal: annual report 2021 to 2022 [Accessed 9 October 2023] ↩ ↩²

9. ONR letter to NDA, ref CNI/22/033, September 2022. ↩

10. ONR, 2019. Licensing nuclear installations. [Accessed 5 October 2023]. ↩ ↩²

11. Environment Agency and ONR. Optimisation for radiological protection. GDF regulatory observation GDF_RO_002. Closed August 2018. ↩

12. Environment Agency and ONR, 2022. Assessment of innovative packaging proposals and their impact on the Disposal System Technical Specification and Safety Case. Regulatory Issue GDF_RI_005. Assessment of NWS response (3). ↩