The UK has a significant inventory of radioactive waste (projected to reach 750,000 cubic metres - enough to fill Wembley Stadium), that will be radioactive for over 100,000 years. For this reason, it is necessary to dispose of the waste safely in a geological disposal facility, isolated several hundreds of meters below the ground. The facility is carefully designed to reduce the likelihood of radioactive substances escaping to the environment. Using a multi-barrier concept, several layers of containment made from a number of different materials prevent groundwater reaching the waste, mitigating the leaching of radioactive substances into the host rock.

Claire is leading UK research efforts to understand and improve the safety functions of this disposal concept. Her research focuses on understanding the mechanisms and kinetics of radioactive waste dissolution in groundwater, determination of the rate of release of radionuclides and the mechanisms by which cement minerals and clays sorb released contaminants. Understanding these processes is critical to developing a safe disposal facility, and will also help the design of new, improved materials for disposal facility. Claire's research applies a range of surface-sensitive and bulk spectroscopy and diffraction techniques, coupled with aqueous geochemical analysis, to the following:

(1) Elucidation of structure-dissolution relationships in crystalline and disorded minerals. Recent research projects have established how atomic structure (related to elemental composition) and micro-structure (e.g. grain boundaries) influence the mechanisms and kinetics of dissolution of minerals in groundwater solutions. Examples include the influence of Ca/Zn content on the dissolution of aluminoborosilicate glass used to immobilise high level radioactive waste and the role of Cr oxidation state in Cr-doped UO₂ fuel on the dissolution behaviour. 

(2) Application of natural analogues to understand radioactive waste degradation. Using natural uranium-containing titanate minerals such as pyrochlore and zirconolite, Claire is developing an understanding of the potential use of such mineral phases for the immobilisation and subsequent geological disposal of large excess plutonium inventories. This work involves spectroscopic investigation of billion-year-old minerals, exploration of the effects of metamictisation, and the development of leaching protocols to understand their durability. Research is also underway exploring the use of weathered natural glasses as analogues for vitrified waste in a disposal facility.

Claire's research sponsors include: UKRI, EU, US DoE, Nuclear Waste Services, Nuclear Decommissioning Authority, Sellafield Ltd., Jacobs and Orano.

She is a member of HM Government's Committee on Radioactive Waste Management, who provide independent scrutiny of, and advice to, the Department of Energy Security and Net Zero on radioactive waste management and disposal. She also sits on the Energy Working Group of HM Treasury's Green Taxonomy, providing advice on the application of nuclear energy in the transition to a circular economy.

Claire is also a keen science communicator and is happy to talk with the media about pretty much anything to do with nuclear energy. She has featured in several documentaries (e.g. C4's Chernobyl: The New Evidence), numerous TV and radio news programmes, as well as printed media outlets. Please drop her an email if you'd like to get in touch.