Evaporator B Return to Service

Evaporator B is in the process of being returned to service to support reprocessing on the Sellafield site, as a result of the successful completion of detailed technical investigations. There was no impact on Thorp or other reprocessing activities on the site while Evaporator B was undergoing investigation following a temporary shutdown.

Last week, during routine operations, the in-built detection system had identified a slight rise in activity levels within one of the top coils of the evaporator. The plant operators followed all the correct procedures to safely shut the facility down promptly. Their use of conservative decision making, following the well rehearsed procedures, demonstrated our ongoing commitment always to put safety before production.
Rigorous tests, carried out over the weekend, eliminated a number of potential causes of this slight increase in activity and no further activity breakthrough was identified. The likely cause was residual activity being removed from the coils following an extended period out of service. The High Active Liquid Effluent Storage Evaporators will continue to be monitored using our existing procedures and we remain vigilant in our safe operations.
Due to the age of the facilities and the nature of the liquor that they process, corrosion within the evaporators is not a new issue. The potential for activity breakthrough from the evaporator coils is an anticipated scenario, and extensively covered by our plant monitoring equipment, procedures and safety case. We continue to work closely with our Regulators and the NDA to both maintain and extend the life of existing evaporative capacity and, through the construction of a new evaporator, to increase and sustain that capacity.
Regulators and stakeholders have been updated throughout the process to ensure there is an appreciation of the challenges faced by Sellafield Ltd and we remain committed to open and transparent communications with all our stakeholders.