The Department of Energy and Climate Change (DECC) has launched a consultation on whether to allow the Nuclear Decommissioning Authority (NDA) not to reprocess small quantities of overseas origin oxide fuels that are either not economic or not possible to reprocess in Sellafield’s Thermal Oxide Reprocessing Plant (THORP) before its currently scheduled closure date of 2018. The consultation closes on 28th May 2014.
DECC says around 300 tonnes of overseas origin spent fuel still remain to be reprocessed, but 30 tonnes of this fuel is made up of small amounts of prototype fuels, experimental fuels, MOX (plutonium) fuels and some materials leftover from research programmes, which would be challenging to deal with through reprocessing, before the planned closure of THORP in 2018. It is thought that around 25 tonnes of this spent fuel is probably spent MoX fuel from Germany.
What the NDA wants to do is to send back to the customer countries an amount of waste and plutonium equivalent to the amount which would be sent back if the spent fuel was reprocessed. This is known as ‘virtual reprocessing’. The NDA says that if THORP were to operate beyond 2018 it would need to build replacement storage tanks for the highly active liquid waste at a cost of around £500m. High level liquid waste generates its own heat, so has to be constantly cooled, which is why the storage tanks are so expensive.
This consultation begs the question: if the Government can sanction “virtual reprocessing” for 30 tonnes of residual spent fuel why can’t the same be done now for the remaining 300 tonnes of overseas fuel and any remaining AGR spent fuel which is still slated for reprocessing so that THORP can shut now? After all, nobody needs any more plutonium.
The UK, as a signatory to the 1998 Sintra Agreement of the OSPAR Convention for the Protection of the Marine Environment of the North-East Atlantic, is committed to achieving “progressive and substantial reductions of discharges, emissions and losses of radioactive substances, with the ultimate aim of concentrations in the environment … close to zero for artificial radioactive substances” by the year 2020. The UK Government’s first Strategy for Radioactive Discharges published in 2002 in response to this commitment said that THORP would close in 2016 unless it found new business. No new business has been found. Given that there is likely to be a time lag due to the need for a post operational clean-out before some radioactive discharges can be stopped after closure, the plant needs to cease operations as soon as possible for the UK to meet its international obligations. (See NFLA / KIMO report on radioactive discharge concerns at Sellafield to the OSPAR, Commission Radioactive Substances Committee, February 2014)
Worse still, the other older reprocessing plant at Sellafield – the Magnox reprocessing plant – which is currently scheduled for closure in 2019, is now unlikely to close before 2022 due to technical problems. (CORE Press Release 16th April 2014) In fact the most recent Magnox Operating Plan (known as MOP9) says the plant may continue operating until 2028 if it performs badly.
While the NDA blames poor throughput for not being able to end Magnox reprocessing by 2012 as originally planned, it has already extended the life of the Wylfa Magnox nuclear station on Anglesey, from March 2010 to September 2014 and is now hoping to continue generating electricity until December 2015 subject to acceptance by the Office for Nuclear Regulation NDA Business Plan (ONR) of the Periodic Safety Review (PSR) and acceptance by DECC of the Business Case. (See NDA Business Plan 2014-17 page 29) The NDA has also started transporting breeder fuel from Dounreay in the north of Scotland to Sellafield for reprocessing, further adding to the inventory of spent fuel to be reprocessed before the Magnox reprocessing plant closes. After Magnox reprocessing ends there are expected to be around five years of continuing radioactive discharges to the Irish Sea due to post-operational clean out.
When it became clear it was not going to be possible to complete the reprocessing of all Magnox spent fuel by 2012, the NDA should have looked seriously at alternative options. Instead it has been extending the life of reactors, and transporting breeder fuel from Scotland which the plant had not been originally scheduled to reprocess.
Reprocessing of Magnox spent fuel has, in the past, been regarded as essential, because it begins to corrode once it has been wetted. Former Sellafield operator, British Nuclear Fuels Ltd (BNFL) finally admitted in 2003 that dry storage would be technically feasible, should the Magnox reprocessing plant break down, having previously claimed Magnox spent fuel MUST be reprocessed. Encapsulating the spent fuel in concrete has also been considered as an alternative fuel management option.
MOP9 now states that:
“The possibility of drying and containerising wetted fuel is currently under development. The work is at a stage where the option is considered technically feasible, further detailed design would be required if it were decided to implement this option.”
Time for the UK to prioritise meeting its international commitments and end reprocessing at Sellafield as soon as possible.