The UK has been producing and managing radioactive waste for many decades. A major part of the Nuclear Decommissioning Authority (NDA) role to decommission civil nuclear sites is enabled through the management of legacy waste. Often these legacy wastes were managed in a way that would not meet today’s standards. The challenges posed in the management of legacy wastes serve as a pertinent reminder of the need to manage waste in a responsible manner to ensure it is safe now and throughout the waste lifecycle. The aim now is to convert wastes to a passively safe and disposable form in a timely manner, reducing the burden on future generations.
The term Higher Activity Waste (HAW) refers to all radioactive material that has no further use that falls into the following categories: High Level Waste (HLW), Intermediate Level Waste (ILW) and the relatively small volume of Low Level Waste (LLW) that is not deemed suitable for disposal at the LLWR or the LLW facility at Dounreay. Our strategy involves converting the HAW within the NDA estate into a form that can be safely stored and managed.
The NDA published a Gate A Credible Options paper on HAW management in 2011. Due to the diversity of wastes to be managed and the complex relationships with other NDA driving strategies it is not considered possible to pursue a Gate B preferred option position (as outlined in our Strategy Management System) that is applicable to all HAW and it was decided that a standalone strategy for NDA HAW should be developed. The 2016 NDA HAW strategy promotes the pursuit of preferred options for HAW at a detailed level, eg for components of the HAW inventory such as graphite.
HAW cannot be simply retrieved and directly disposed of. Waste management requires a series of lifecycle steps through which it is important to consider the waste hierarchy: pursuing opportunities for waste minimisation, re-use and recycling, before undertaking treatment, packaging and storage. The waste must then be stored safely pending future transport and then final disposal, when a disposal facility is available.
NDA’s HAW strategy
The NDA’s HAW strategy is to convert the HAW inventory into a form that can be safely and securely stored for many decades. At the appropriate time the stored waste in England and Wales will be transported to and disposed of in a geological disposal facility (GDF) and the NDA will continue to work with Scottish government to implement its policy for the long-term management of HAW at its sites in Scotland.
The NDA recognises that there are well established plans in place for the management of HAW across the estate and the HAW strategy is to progress these plans (the ‘reference strategy’) while at the same time seeking to:
- identify and promote good practice
- give guidance and leadership in key strategic areas
- pursue opportunities to make overall improvements
The HAW strategy aims to foster the benefits of improved efficiency for the management of HAW across the NDA estate while supporting the technical challenges in implementing the reference strategy. The strategic themes can be broadly described as:
- application of the waste hierarchy
- development of alternative waste management routes
- making best use of existing and future planned assets
Introducing strategic change
We recognise that the near-term waste management plans can often be well established making it more difficult and less beneficial to change course. The main opportunities to introduce strategic change to bring significant benefit occur in the longer term where planning is at an early stage and less mature. We also recognise that SLCs are the strategy implementers and have the primary responsibility for ensuring safety, security and environmental performance at their sites at all times.
The desired outcome of HAW strategy is that waste is well managed by our Site Licence Companies (SLCs), in a manner that supports operational and decommissioning needs. This means greater focus on all aspects of the waste lifecycle and includes strategic evaluation to consider whether waste is better managed by sites working independently or by them sharing assets and capabilities.
It is important to recognise that the NDA HAW strategy applies to HAW within the NDA estate and is delivered under contract by the SLCs, such that the NDA is the strategic authority and client. Although this strategy is for the NDA-owned HAW we work with other owners of smaller volumes of HAW to encourage good practice and knowledge transfer across the whole of the industry.
Recognition of different policy for long-term management of HAW in Scotland
This strategy recognises that within the UK there are policy differences regarding the long-term management of HAW in England and Wales to those in Scotland. The NDA works with the relevant governments to provide management solutions that are consistent with these different policies. The UK policy on the long-term management of HAW recognises that it is appropriate to investigate alternative options to a GDF for some of the inventory where there could be the potential to improve the overall management of HAW. To support this UK policy and the Scottish government policy position of near-surface management of HAW we will explore a range of disposal options together with RWM and our SLCs.
Current UK policy classifies radioactive waste into categories depending on the nature and quantity of radioactivity they contain and whether they generate heat or not. The NDA (with support from the nuclear site regulators) advocates an approach where wastes are managed based on their best means of disposal rather than what waste category they fall into.
The NDA is moving towards a single radioactive waste strategy for its estate that will need to demonstrate how it will support all relevant policies in the UK. Our radioactive waste strategy will not replace the use of existing waste categories (e.g. ILW, LLW). It will also need to take into account the nature of wastes (radiological, chemical and physical properties) and the most appropriate waste management route while recognising the challenges posed by waste classification boundaries. Considerable stakeholder engagement will be required as the strategy develops over the next few years.
NDA is seeking views on this Higher Activity Waste Strategy 2016.