Question

To ask the Secretary of State for Energy and Climate Change, if he will make an assessment of the danger to the public as a result of cracks in the graphite of a reactor at Hunterston B nuclear power station, North Ayrshire; and if he will make a statement.

Assessing the safety of nuclear stations is a matter for nuclear sites and the independent nuclear regulator, the Office for Nuclear Regulation (ONR).

Under the terms of its licence, a licensee is required to produce a safety case to demonstrate the continued safe operation of its reactors to the satisfaction of ONR. The licensee at Hunterston B, EDF Energy Nuclear Generation Ltd, notified ONR of the cracking of two graphite bricks in the core of Hunterston B (Reactor 4) on 21 August 2014. The type of cracking identified is termed ‘keyway root cracking’ and it has been considered by the licensee in its safety case. ONR’s technical experts confirmed that the cracks identified were well within the safe limits of operation set within the safety case and that they do not pose an increased risk to the public. On this basis, ONR was satisfied with the licensee’s justification for the return to service of Reactor 4 at Hunterston B and issued a Consent to restart Reactor 4 on the 29^th September 2014.