Hunterston A laboratory closed after SEPA issue warning

But the team behind the decommissioning of the plant, Nuclear Restoration Services (NRS), insist there is no danger to the public.

The notice was issued after it was discovered that some of the plant's radiological sample analysis equipment located in the lab may not have been calibrated to the required standard.

NRS reported the potential issue to SEPA themselves.

SEPA said the problem meant Hunterston A had breached their permit for the lab.

In a letter to stakeholders at the plant today, acting site director Richard Gibson said: "SEPA has issued a regulatory notice which requires NRS to undertake steps to ensure compliance with our environmental permit in respect to the on-site radiochemistry laboratory at Hunterston A.

"It has been issued because some of our radiological sample analysis equipment located in the site laboratory may not have been calibrated to the required standard.

"We promptly reported this to SEPA, and are working to ensure that the situation is rectified. 

"We believe we have continued to operate within our permitted discharge limits, with no additional risk to staff, the public and or the environment.

"Site radioactive discharges are low and well within the levels stated within the permit.

"Samples will be analysed in alternative laboratories until SEPA is content the measures contained within the notice have been satisfied."

NRS said the issue was first noticed in late August. They identified that there was a suspected anomaly with the calibration of the site’s radiochemistry laboratory counting equipment.

This is used to measure radiological liquid and gaseous discharges and the anomalies relate to the absence of evidence showing that valid calibrations had been undertaken.

A site investigation was undertaken and SEPA was promptly informed. The internal investigation identified improvements that were required to some processes, including  operating procedures.

SEPA visited the site in October and an overview of the internal investigation was provided. As a result, SEPA advised that a regulatory notice would be issued, which required NRS to close the lab.

NRS said: "As a consequence, higher active waste operations have been temporarily paused and some work in radiological controlled areas is being limited.

"A small percentage of employees have been temporarily re-deployed in other areas of work on site.

"We are sourcing alternative off site laboratory facilities, including the use of our own facilities at Chapelcross site and the first samples for analysis were sent there this week.

"This will enable us to return to normal decommissioning operations while the matter is resolved."

SEPA has been approached for comment.