A SERIES of safety failure at Hunterston could have had 'serious consequences' if the reactors had been in full operation, it was claimed this week.

The Nuclear Free Local Authorities group, which is made up of councillors around the UK concerned about nuclear power, described the incidents as 'notable'.

The incident which prevented cooling gas from being circulated around a reactor was highlighted by the group as 'a real concern'.

However the nuclear regulators described the incident as 'minor' as both incidents happened when both reactors were offline.

In relation to the incident, a spokesperson for Nuclear Free Local Authorities said: "Whilst there were no radiological consequence from them, this is largely due to the reactors not being in operation.

"A loss of cooling is of real concern as the consequences of such an eventuality when the reactors are in full operation could have been extremely serious."

Other recorded incidents included cooling for a reactor being temporarily lost, a shutdown pump failing and smoke coming from a control room panel.

A spokesperson for the Office for Nuclear Regulation (ONR) said: "The public should be assured that the incidents referenced in the recent quarterly site report are not connected to the graphite core issues present at the reactors at Hunterston B.

"Nuclear plants are designed and operated to deal with unexpected events that occur and there are multiple safety barriers to stop those events becoming more serious.

"Due to this defence in depth, the types of incidents in question were relatively minor and there was no risk of harm to people or the environment.

"However we are not complacent and we consider every event and will take appropriate regulatory action where necessary to ensure the safety of workers and the public."

A spokeswoman for EDF Energy said: “EDF has an open reporting culture and we brought these incidents to the ONR’s attention as soon as they happened as part of the usual processes.

"Each of the issues were very minor and did not pose a risk to workers, the public, or the plant itself. We have strength in depth on all our safety systems, and our back-systems remained available and maintained the safety of the plant at all times.

"We investigate incidents thoroughly so we can learn from them and improve our stations’ operations in the future.”

An issue had recently been identified concerning the need for further analysis of the significance of crack openings greater than 1.2 cm wide.

An ONR spokesman said: “During the assessment of the Reactor 4 safety case, ONR’s specialist inspectors have engaged extensively with EDF Energy in technical discussions to ensure that all significant issues are addressed. We maintain regular dialogue with EDF Energy as we continue to examine and challenge the claims made in their safety case.

"Our specialist inspectors continue to examine the evidence provided by EDF Energy and the reactors will remain offline until we are satisfied that they can be operated safely for a further period.”

Regarding switching on the reactors, Hunterston B Station Manager Colin Weir said: "To support time for the ONR assessment, we have declared 30 August 2019 for Reactor 4, a slight adjustment to the previously declared date of 5 August. Our target for Reactor 3 remains as 1 October."