A mishap at a naval nuclear reactor near Dounreay - said by the Defence Secretary, Philip Hammond, to have caused no environmental pollution - in fact triggered a tenfold rise in radioactive gas emissions.
The revelation, unearthed by a Sunday Herald investigation, has prompted the First Minister, Alex Salmond, to accuse Hammond of deceiving parliament. He is also writing to the Prime Minister, David Cameron, demanding an apology.
The problem at the Vulcan plant in Caithness, which tests submarine reactors for the Minister of Defence (MoD) occurred in January 2012. But the first the public and Scottish ministers knew about it was when Hammond made a statement in the House of Commons on Thursday.
He told MPs that there had been “no measurable change in the radiation discharge” from the site. “That is the important point for people living in those communities,” he said.
Radioactivity had leaked into the reactor’s cooling water but been contained within the sealed reactor circuit, Hammond stated. “I can reassure the House that there has been no detectable radiation leak from that sealed circuit.”
But according to the Scottish Environment Protection Agency (Sepa), which monitors emissions from the plant, discharges of radioactive ‘noble’ gases like argon, krypton and xenon had been boosted by the incident. Official figures show that emissions of the gases to the atmosphere rocketed from 0.19 gigabecquerels of radioactivity in 2011 to 2.16 Gbq in 2012.
“What a tangled web Hammond weaves when he practices to deceive,” Salmond told the Sunday Herald. “The emissions were indeed measurable and they were measured by Sepa.”