An investigation has been launched by Sellafield Ltd into another incident involving the loss of coolant water to the site’s HLW tanks – the second such incident within the last ten months.
The loss of coolant to the tanks’ highly radioactive inventory of liquid wastes occurred on Friday 22nd January 2010 – and follows a similar loss in April 2009. Breaking the news, this week’s Whitehaven News (26th January) says that 4 of the site’s 21 storage tanks were affected and that the loss of cooling water lasted for 30 minutes. The loss of coolant in the April ’09 accident lasted several hours (see CORE Press Release 8th April 2009).
An extended loss of coolant to the storage tanks has the potential for a major accident involving the off-site release of a plume of radioactivity. As such, an accident involving such a loss is designated as the ‘worst credible accident’ (Reference Accident) under the Emergency Plans for Sellafield.
Sellafield Ltd has said that as a result of last week’s incident ‘there was no release of radioactivity, nobody was injured and it has had no impact on reprocessing operations and waste management’. The Company has declined to provide any further detail of the accident because of the ongoing investigation.
The Nuclear Installations Inspectorate (NII) has been informed of the accident and has launched its own full investigation. Confirming that the loss of coolant lasted for around 30 minutes, the NII believed the loss may have affected ‘a considerable number’ of the HLW storage tanks.
Ironically, the loss of coolant accident last Friday occurred as the NII were about to complete their full investigation into last April’s event and decide what action should be taken against Sellafield Ltd. That decision will now be put on hold until the implications of the latest accident have been fully considered, particularly the effectiveness of the measures that had to be put in place following the previous accident.