Hunterston: Astonishing decision by UK nuclear safety regulator

News from the Celtic League:

The UK Nuclear regulator the ONR is to allow Hunterston B nuclear power plant to restart the plant had been taken out of drive because of cracking in the reactor core. However astonishingly the decision is not because the reactor is safe but because the regulator has allowed the safety margins to be relaxed.

Previously operational cracking was not allowed to exceed 350 axillary cracked bricks bit this allowance has now been DOUBLED to 700.

Here is the relevant section of the report:

The safety case is based upon an increase in the operational allowance to 700 axial cracks and an upper safety limit of 1331 axially cracked bricks

The full report and ONR press release are here:

http://www.onr.org.uk/pars/2019/hunterston-b-19-004.pdf

http://news.onr.org.uk/2019/08/hunterston-b-reactor-4/

The fact that the UK lost a significant part of the grid recently which indicates lax surplus capacity and the immanence of winter are clearly factors influencing this decision which in safety terms based on previous practice is not just nonsense but dangerous.

A serious failure of the reactor at Hunterston poses an environmental danger not just for Western Britain and Ireland but also parts of Europe. We are still living with the legacy of Chernobyl and that was a lot further away than Hunterston B!

The Celtic League will be writing to the IAEA to ask if it endorses the revised safety case.

Bernard Moffatt

Assistant General Secretary
Celtic League