When the NDA took over the UK’s nuclear liabilities, it inherited around 700kg of High Enriched Uranium (HEU) at Dounreay which had to be removed to enable progress towards decommissioning and remediation of the site. We had plans to transport the HEU to Sellafield for safe and secure interim storage pending the development of a disposition route.
In 2014, we began to evaluate an alternative plan to send the material to the USA for down-blending and reuse as fuel in civil nuclear reactors in exchange for the supply of a different form of the material to Europe for use as research reactor fuel and in the production of medical isotopes. This would remove the HEU from Dounreay and also provide ultimate disposition of the material while realising cost benefits compared with the original plan (SO25).
The programme supported the Memorandum of Understanding (MOU) signed in 2014 between the US Department of Energy / National Nuclear Security Administration (US DOE / NNSA) and the Euratom Supply Agency (ESA) (ref 30). This MOU recognised the need to provide limited supplies of HEU from the USA for medical isotope production and research reactor fuel until facilities in Europe converted to using Low Enriched Uranium (LEU). In turn, the European Atomic Energy Community (Euratom) identified excess, unirradiated HEU that could be down-blended to LEU for use as nuclear fuel.
At the 2016 Nuclear Security Summit, the Prime Minister announced the UK’s intention to transfer the HEU from Dounreay to the USA. The UK’s Statement (ref 31) noted: “The transfer will consolidate and achieve a net reduction in global HEU holdings, whilst providing real societal benefits.”
Our HEU included a broad range of materials and more than 1,250 individual items that varied greatly in form and enrichment, reflecting the extensive fuel cycle operations that Dounreay had performed over the course of 4 decades including research reactor fuel fabrication and reprocessing.
The transfer campaign was complex, with an array of technical, logistical, safety and security considerations. Approximately a dozen organisations from the USA and the UK worked together in its planning and execution, requiring many hundreds of hours of work by all the organisations involved to ensure the secure movements of the material:
- US DOE / NNSA’s Office of Material Management and Minimisation (M3), the Y-12 National Security Complex (Y-12), Dounreay Site Restoration Limited (DSRL) and the NDA led the effort
- DSRL modified an existing glovebox and installed a new uranium processing line to treat and package the materials for transport
- transport packages of both US and French origin were used. ONR, US DOE and US Department of Transportation approved and validated the licences of both types of package and their payloads and ONR approved the transport security arrangements for each shipment
- the UK Civil Nuclear Constabulary, Police Scotland and MOD Police provided policing and maintained security for the land transports
- the US Air Force provided air transport to the USA using C-17 aircraft
- amendments to the UK’s Nuclear Industries Security Regulations were made to widen the powers of ONR to regulate transport of fissile material by air. These amendments required approval by the UK Parliament
- Highlands and Islands Airports Limited (HIAL) refurbished the runway at Wick John O’Groats airport as well as other airport infrastructure; this will support future airport usage
- the Defense Threat Reduction Agency (DTRA) of the US Department of Defense contributed to the logistics effort. DTRA’s Cooperative Threat Reduction (CTR): Global Nuclear Security Program (GNS) provided funding for the air transportation as well as dedicated equipment used to prepare the cargo for air transport. DTRA personnel were also involved in preparation and loading activities at the point of departure.
The USA and UK organisations held detailed planning meetings in the UK in advance of each shipment. Lessons learned from the previous shipments were reviewed and adjustments made to the preparatory activities, logistics, and operational timeline. Over the course of the project, the stakeholders also conducted 2 table-top exercises to discuss contingencies and refine planning assumptions.
A total of 6 shipments to the USA were completed safely and securely between 2016 and 2018 (ref 32, 33).
The successful completion of the project represents an important milestone in the programme to decommission and clean up the Dounreay Site. The work contributed to mutually beneficial strategic outcomes for multiple organisations internationally.
- March 18, 2021 at 2:03 pm by Editor (displayed above)
- March 18, 2021 at 2:03 pm by Editor