The power company, EDF Energy, has come under fire for advising that the emergency zone to protect people around its cracked nuclear reactors at Hunterston could be shrunk to a kilometre.
The current zone – within which evacuation, sheltering and anti-radiation pills are planned in the event of an accident – is a radius of 2.4 kilometres from the nuclear power station on the Ayrshire coast.
But EDF has now told North Ayrshire Council that urgent protective measures were “justified within a maximum distance of 1km from the site for protection of the public”. Its assessment was based on the “most pessimistic” assumptions, it said.
Campaigners have criticised EDF’s move, warning that an accident could send a plume of radioactive contamination over Glasgow and Edinburgh. They have called for the emergency zone to be expanded, not contracted.
EDF stressed that its advice was that one kilometre was the “minimum” recommended distance. North Ayrshire Council is consulting with local residents before it decides what distance to implement.
Safety fears as Hunterston’s cracked nuclear reactors start to crumble
The Ferret revealed in October that the graphite cores of two ageing nuclear reactors at Hunterston B have begun to crumble as cracks spread and widen. According to the UK government’s Office for Nuclear Regulation (ONR), at least 58 fragments and pieces of debris have broken off the graphite bricks that make up the reactor cores.
The older reactor, three, has an estimated 377 core cracks and has been shut down since 9 March 2018. ONR is assessing the safety case to decide whether it can be allowed to restart in 2020.
Reactor four, which has an estimated 209 cracks, was shut down for over ten months before ONR allowed it to restart in August – but only for four months. EDF is currently planning to shut it down again on 10 December.
Government rules for protecting the public against accidents releasing radioactivity require local authorities to determine detailed emergency planning zones around nuclear plants. This is an area within which people may be evacuated, told to stay indoors, or given iodine tablets to block thyroid contamination by radiation.
Under the rules nuclear companies have to produce a “consequences report” giving local authorities the technical justification for the minimum size of the emergency zone. EDF’s report to North Ayrshire Council suggests that the zone around Hunterston could be a radius of one kilometre instead of the existing 2.4 kilometres.
“Detailed planning is justified at Hunterston B power station within at least 1km and the urgent protective actions of administration of stable iodine and implementation of sheltering are justified within a maximum distance of 1km from the site for protection of the public,” the report concludes.
“There is no justification for planning in detail to evacuate the public within a detailed emergency planning zone.”
EDF accepts, however, that food restrictions may be required over a much wider area. “It is recommended that advice be issued within 24 hours to restrict consumption of leafy green vegetables, milk and water from open sources/rain water in all sectors of the detailed emergency planning zone and downwind of the site to a distance of 43km,” it says.
The imagined release of radioactivity “assumes the most pessimistic attributes from a number of fault sequences,” says EDF. The company “considered a wide range of accident scenarios in our hazard evaluation process and selected a candidate release as the basis of the consequences assessment.”
Campaigners have previously warned that a serious accident at Hunterston could spread a cloud of radioactive contamination over Glasgow, Edinburgh and the central belt, if the wind was blowing in that direction. It could be like the Chernobyl accident in Ukraine in 1986, they claimed.
Radiation consultant, Dr Ian Fairlie, described EDF’s report as “deficient” and “misleading”. The suggested emergency zone was “much too small”, he argued, and there was a “lack of openness and clarity” that would leave local people uncertain what to do in the event of a major accident.
He added: “The issue of the pre-distribution of prophylactic potassium iodate tablets is not mentioned. This already occurs in most European countries, and should occur here as well in order to avoid the health consequences of breathing in radioactive iodine which is a gas.”
Rita Holmes, who chairs Hunterston’s local stakeholder group, pointed out that at the moment only 13 households close to the plant were given iodine tablets in advance. “It would seem a simple precaution and unwise not to pre-distribute within a wider area,” she told The Ferret.
“Despite EDF’s assessment, I hope that our local authority, Ayrshire civil contingencies team and ONR will decide to extend the detailed emergency planning zone and pre-distribute stable iodine to people within a wider area. I certainly don’t expect, given the ageing reactor cores, that the zone would be shrunk.”
The 50-strong group of nuclear-free local authorities argued it would be “incongruous” if the emergency zone was reduced, given the deterioration of the Hunterston reactors. “Clear question marks remain over their future operation,” said the group’s policy advisor, Peter Roche.
“In our view the precautionary principle would suggest a much larger emergency planning zone is drawn to provide greater reassurance to the local population.”
Friends of the Earth Scotland pointed out that seven years after the explosions at the Fukushima nuclear reactors in Japan in 2011, some areas more than 20 kilometres away were still prohibited zones. “The current Hunterston zone is already very modest in comparison to the very large area which would be affected in the event of a serious accident at the plant,” said the environmental group’s director, Dr Richard Dixon.
“With increasing worries about the safety of the reactors at Hunterston now is definitely not the time to reduce the level of protection on offer to the local community,” he argued.
“EDF are the last people who should propose what size the exclusion zone should be around their own nuclear sites because it is in their financial and PR interests to make the zone as small as possible.”
Probes into four safety incidents at Hunterston nuclear plant
North Ayrshire Council is planning to agree a detailed emergency planning zone for Hunterston in January. “We can go beyond the operator’s recommendations if there is clear justification based on factors detailed in the regulations,” said the council’s head of democratic and administrative services, Andrew Fraser.
“To help inform this we are consulting with Public Health England’s centre for radiation, chemical and environmental hazards and also consulting those within the current 2.4km zone. Consultation responses will help inform whether there is a case to go beyond the 1km recommended by EDF.”
A letter to local residents on 12 November suggests the council is considering three options. One is EDF’s one kilometre zone and a second is a zone “using the natural boundary of the A78.”
The third option would also use the A78 but include all households which are currently within the zone. This is the closest to the existing zone, the council said.
EDF Energy pointed out that recent changes to the rules put the responsibility for setting the size and shape of detailed emergency planning zones (DEPZ) on to local authorities. “It is completely incorrect to suggest that EDF Energy is urging North Ayrshire Council to reduce its emergency planning zone,” said a company spokesperson.
“The regulations require that all nuclear operators provide technical advice to each local authority on the minimum distance recommended for the DEPZ. This advice, based on robust information already accepted by the independent regulator, ONR, would not affect health risks.
“The final decision on the DEPZ rests with the local authority which will consider this report alongside other local factors.”
EDF Energy’s consequences report for Hunterston B
Hnb Reppir Consequences Report (Text)
North Ayrshire Council’s letter to local residents
DEPZ Residents 7 November 2019 (Text)
Photo thanks to Thomas Nugent, licensed for reuse under this Creative Commons Licence.