Reprocessing ceases at UK's Thorp plant

14 November 2018

Reprocessing operations have ended at the Thermal Oxide Reprocessing Plant (Thorp) at the Sellafield site in the UK after 24 years. The facility will now be used to store used nuclear fuel until the 2070s.

The Thorp reprocessing plant (Image: Sellafield Ltd)

Built at a cost of GBP1.8 billion (USD2.3 billion), the Thorp facility opened in 1994 and has since processed 9331 tonnes of used nuclear fuel from 30 customers in nine countries around the world.  In doing so, it has generated an estimated GBP9 billion in revenue. It is one of only two commercial nuclear fuel reprocessing plants in the world, the other being Orano's La Hague plant in France.

The decision to cease reprocessing at Thorp was taken in 2012 in response to "a significant downturn" in demand, said Sellafield Limited. "The international market for reprocessing has shifted significantly since Thorp's construction, with the majority of customers now opting to store rather than reprocess their fuel."

The last batch of fuel to be reprocessed began its journey through the plant at 11.32am on 9 November.

Sellafield Ltd said the Thorp plant - the largest structure on the Sellafield site - "will continue to serve the UK until the 2070s" as a storage facility for used fuel.

The Sellafield site, it said, "is being reinvented as a centre of expertise for nuclear clean-up". This will "unlock 100 years' worth of opportunity for the site's workforce, supply chain, and community".

Paul Foster, CEO of Sellafield Ltd, said: "As we look forward to an exciting future, we want to celebrate the best of our past. The end of reprocessing at Thorp is one of the most important events in Sellafield's history."

He added, "I'm immensely proud of Thorp's contribution and I'd like to thank the workforce for their unwavering dedication and professionalism throughout a period of unprecedented change."

Following its creation in 2004, the UK's Nuclear Decommissioning Authority (NDA) inherited a range of contracts covering the reprocessing and storage of used oxide fuels at the Thorp facilities. These include used light water reactor fuels from Europe and Japan that were being stored at Sellafield pending reprocessing in Thorp, as well as the used fuel from the UK's fleet of Advanced Gas-cooled Reactors.

In June 2012, the NDA concluded that completing existing reprocessing contracts at Thorp remained a "viable and cost-effective strategy". The plant had been expected to complete the reprocessing contracts by 2010, but was unable to due to "operational difficulties both in Thorp and in downstream support plants". Thorp was shut down between May 2005 and December 2007 due to an internal leak of highly radioactive liquor from a fractured pipe. The loss of the pipe, which could not be repaired, meant a work-around method had to be developed to maintain the plant's process flow.

Researched and written by World Nuclear News