Achieving the End State of a Nuclear Licensed Site

End State refers to the condition of a nuclear licensed site (or part of the site) following all physical decommissioning and clean-up activities required to make the site (or part of the site) available for its next use. To reach the End State, a site must be compliant with the requirments for release of the site from environmental regulations. Site operators may apply to the environment agencies for agreement for a site to be released from radioactive substances regulation (RSR). The release of the site will only be granted when all disposals of radioactive waste have ended and the site is in a state that will ensure a satisfactory standard of protection for people and the environment. A guidance document, known as “the GRR”, on the release of nuclear sites from RSR was published in July 2018. A site specific assessement of the benefits and detriments of clean-up and radioactive waste disposal options must be carried out as a requirement of the GRR. This involves identification of potential disposal options, assesssment and comparison of options, with stakeholder engagement, and optimisation of the preferred option if any radioactive material is to be left on site. As part of the assessment of waste disposal options, the GRR requires that operators assess potential consequnces of inadvertent human intrusion into the site, and aqueous releases from features on the site after the End State has been reached. Calculations of potential impacts from human intrusion and aqueous release scenarios are carried out and compared against guidance levels specified in the GRR. These assessments should also show that the consequential effects on non-human species are acceptable. Results of these assessments allow consideration of the implications of leaving radioactivity associated with particular features and components of the site, and inform comparison of alternative End State options.