Welcome to the Spring 2006 edition of Quintessa Update, the electronic newsletter of Quintessa Limited

Support to the Development of the Lifetime Plan for the Low-level Waste Repository at Drigg

The long-term safety of the Low-level Waste Repository (LLWR) near the village of Drigg, Cumbria was assessed in 2002 and submitted to the regulator, the Environment Agency, as part of a review of the continued authorisation of the facility. The outcome has been the recognition that key issues need to be addressed to provide a robust safety case for the facility. Failure to make this case could have major implications for the management of LLW in the UK. Since late 2005, Quintessa has had a major involvement in helping British Nuclear Group, Sellafield Ltd to develop a Lifetime Plan for the LLWR. This provides an integrated approach to tackling the key issues such as:

  • Addressing key regulatory requirements for the continued authorisation of the LLWR;
  • Supporting the derivation of the Site End State by the Site Stakeholder Group;
  • Planning and preparatory work for the next iteration of the Post-Closure Safety Case within an overall Environmental Safety Case; and
  • Developing a strategy for key issues such as the potential vulnerability of historic trenches to coastal erosion.

Nexia Solutions have been working with Quintessa to support aspects of the Plan.

CoRWM Draft Recommendations

The Committee on Radioactive Waste Management (CoRWM) delivered its draft recommendations for the long-term management of the UK's intermediate and high-level radioactive waste in Brighton on 27 April. Quintessa has been providing independent facilitation support to CoRWM during an intensive period of work over the last few months, working closely with the Committee as it formulated its recommendations. The recommendations are intended to be read as an integrated package and envisage that, in the long term, radioactive waste will be disposed of through geological disposal. However, they also incorporate a recognition that the process leading to the creation of suitable facilities for disposal may take several decades and should therefore be underpinned by robust interim storage. The location of sites is not part of the CoRWM remit, but the Committee believes that host communities should be identified on the basis of a willingness to participate and an equal partnership approach to decision-making.


The UK Department for Environment, Food and Rural Affairs (Defra) is extending the existing contaminated land regime under Part 2A of the Environmental Protection Act 1990 to cover radioactivity. Defra commissioned Quintessa, with support from URS Corporation, to develop a 'Radioactively Contaminated Land Exposure Assessment' (RCLEA) methodology for the quantitative risk assessment of land that falls under the regime. A software tool has also been developed, using Microsoft Excel ®, to enable RCLEA to be applied.

Post-Closure Safety Case for the Dounreay Shaft

UKAEA has recently issued a contract to Quintessa to develop the next two issues of the Preliminary Post-Closure Safety Case (PCSC) for the Dounreay Shaft, building on our previous work to establish the Preliminary PCSC for the Shaft. The work will involve maintaining and further developing the suite of Preliminary PCSC documents and associated performance assessment models, and targeted analysis to reduce key uncertainties in the long-term safety of the closed facility.

Publication of results from the Tono Natural Analogue Project

Quintessa has contributed to a thematic set of papers that describe results from the Tono Natural Analogue Project (TAP). This project was undertaken by the Japan Nuclear Cycle Development Institute (JNC; now part of the Japan Atomic Energy Ageny, JAEA) and focused on the Tsukiyoshi uranium ore body in the Tono area of central Honshu, Japan. These papers were published in January 2006, in Issue 17 of the journal Geochemistry: Exploration, Environment, Analysis.

Cooperation with Oxand

Quintessa and Oxand have agreed to cooperate by seeking joint projects related to risk assessment and risk management for the nuclear industry and the geological storage of carbon dioxide. Oxand is a French based civil engineering consultancy that has leading-edge expertise in analysis and decision-support related to the ageing of cement-based structures - particularly for nuclear power plants, radioactive waste storage and disposal facilities, and oil & gas borehole seals.

George Towler

Quintessa is pleased to welcome George Towler to the Warrington office. George trained in Earth Sciences and Environmental Modelling and Monitoring, and has more than 6 years experience working in the British Nuclear industry on key sites including Sellafield and the LLWR near Drigg.

For further information on the above topics, please contact David Hodgkinson.