The UK Nuclear Decommissioning Authority (NDA) and US Department of Energy’s National Nuclear Security Administration (NNSA) have completed the transfer of around 700kg of highly enriched uranium (HEU) from Dounreay, in northern Scotland, to the USA.
The HEU transfer was announced on 3 May by the UK Government as part of its commitment to the 2016 Nuclear Security Summit held in Washington DC. During the 1990s, HEU was sent to Dounreay for reprocessing. The customers included power plants and research centres in Australia, Germany and Belgium. Originally, the material was set to be transferred to Sellafield as part of the NDA’s consolidation strategy.
NDA CEO David Peattie said the successful completion of the transfer was an important milestone in the decommissioning and clean up of the Dounreay Site. “The HEU will be down-blended in the US to be used as fuel in civil nuclear reactors - for entirely peaceful purposes. The US is sending a different form of the material to Europe, where it will be used as research reactor fuel and in the production of medical isotopes."
More than a dozen US and UK organisations participated in the transfer. Simon Bowen chairman of the Cavendish Dounreay Partnership, a consortium of Cavendish Nuclear, Jacobs and AECOM that owns and manages Dounreay Site Restoration Ltd under a contract with the NDA, praised the collaborative approach taken by the Dounreay team, the supply chain and the other organisations involved.
The HEU was moved in batches from Dounreay to Wick John O'Groats Airport and then flown to the USA using US military Boeing C-17 transport aircraft.
Global engineering firm Wood designed, built and commissioned the equipment and facilities needed to repackage the nuclear material so that it could be flown to the USA. This included installing a suite of glove boxes inside a purpose-built, seismically-qualified structure within an existing facility for handling the HEU. Manufacturing of the gloveboxes was supported by Caithness-based Gow’s Lybster Ltd, Hampshire-based Aquila Nuclear Engineering and Oldham-based Universal Fabrications (North West) Ltd. Wood was reponsible for all aspects of engineering, and carried out hundreds of software calculations to demonstrate process safety covering both radiation protection and criticality.
Removal of the material from Dounreay is part of a worldwide effort to increase nuclear security by reducing HEU inventories. It also is part of a 2014 agreement between DOE/NNSA and the Euratom Supply Agency to reduce HEU while supporting medical isotope production and research reactors in Europe.
Photo: Dan Andrews, Wood engineering manager, carrying out tests on the gloveboxes during commissioning