Site End/Reference State Support

When nuclear sites have reached the end of their useful lives, the operator must undertake a programme of decommissioning and clean-up of the site, to enable the site to be released from nuclear and radiological regulations. The condition of the nuclear site at that time is referred to as the “End State” (or “Reference State”). Clearly defining the objectives for the final condition of a nuclear site is central to the decommissioning and restoration strategy, providing a key focus for the work to be undertaken.

Identifying and developing the End State for a nuclear site is usually a two-stage process:

  • first, a decision is needed on the overall strategy for closing the site and dealing with the wastes from decommissioning and clean-up, together with any land contamination;
  • when this has been established, it is then necessary to decide how this can be achieved for the specific structures, facilities and features that are present.

Quintessa has been supporting nuclear sites at both these levels of decision-making for nearly 20 years, in many cases with first-of-a-kind work. This has involved developing a clear understanding of what information is needed to take such decisions, and how to deal with the inevitable uncertainties. A major component to the process, particularly at the “strategic” level, is also stakeholder engagement. We have provided support to engagement processes at a variety of levels, from preparing briefing information to facilitating workshops.

We also recognise that the outcomes of End State decision-making need to be translated into achievable programmes of work and can provide key information to achieve this. In particular, we can use our well-established capabilities in safety assessment to help establish specific criteria and targets for decommissioning and clean-up, with supporting regulatory submissions such as a Waste Management Plan and Site-wide Environmental Safety Case.