Despite strenuous denials by Sellafield managers late May in local newspapers that THORP was facing closure, it has now been confirmed that the plant will indeed be closed down shortly for a period of some seven months.
Details of plant’s imminent shut-down were given to CORE in a meeting with the NDA, Sellafield Ltd and Nuclear Management Partners (NMP) on 2nd June when it was revealed that Evaporator C, the only site Evaporator configured for THORP use, was shortly to be taken out of service for an in-depth engineering investigation to assess its remnant operational life. The extended shut-down, planned to last for 7 months, will include an investigation into the thickness of the Evaporator’s internal cooling coils, a period for evaluation of the data from the investigation and the eventual the making of a new safety case to the HSE’s Nuclear Installations Inspectorate (NII) for any further use of the Evaporator by THORP.
CORE’s spokesman Martin Forwood, commenting on the closure said:
This vindicates the claim made in our Press Release of 18th May that, as a result of problems in evaporating the liquid high level wastes from reprocessing, THORP’s future was balanced on a knife-edge. It also highlights the true worth of Sellafield’s assurances to its worker, in response to our claim, that there would be ‘no plant closures’.
In the summer of 2008, NII approved a limit of 300 tons of oxide fuel from THORP reprocessing to be processed through Evaporator C. With some 235 tons now processed, the limit is expected to be reached within the next few weeks, at which point the Evaporator will be taken out of service. Any future operation of Evaporator C is dependent not only on the outcome of the investigation but also on Sellafield’s ability to convince the NII that, in tandem with the site’s two older Evaporators (A & B), there will be sufficient evaporative capacity to process not only THORP liquid wastes, but also those from Magnox reprocessing and the Vitrification Plant: both prioritized for processing by the NII over wastes from THORP.
Whilst the loss of Evaporator C will bring THORP reprocessing to a standstill, processing of the Magnox and Vitrification wastes will be undertaken solely by Evaporator B which itself was briefly taken out of service just two weeks ago with suspected problems with one of its two remaining cooling coils (from four originally fitted).
Evaporator A, which now relies on just one of its original four coils, is not in service and kept as a contingency for processing Vitrification wastes should Evaporator B run into further problems. Operation of a new Evaporator D, planned to help THORP complete all its contracts, was originally scheduled for 2010 but is now not expected until 2014.
Completion date for all THORP's contracts, originally scheduled for 2010/11, was put back to around 2015 as a result of its extended closure in 2005 following a major leakage accident, and is now projected to be in 2017.
Source: Press release CORE, 2 June 2009
Contact: Cumbrians Opposed to Radioactive Environment (CORE), Dry Hall, Broughton Mills, Broughton-In-Furness, Cumbria LA20 6AZ, United Kingdom.
Tel +44 1229 716523