NEW cracks have been discovered in one of Scotland’s ageing nuclear reactors, raising radiation safety fears and resulting in a prolonged shutdown, the Sunday Herald can reveal.

Checks have detected fresh cracks in the graphite core of a reactor at Hunterston B in North Ayrshire. The reactor was taken offline on March 9, but is not now due to restart until May 1 at the earliest, more than a month later than originally planned.

The UK Government safety watchdog, the Office for Nuclear Regulation (ONR), is assessing whether the cracks render the reactor too dangerous to fire up. Its operator, EDF Energy, insists it will reopen, but critics say it should stay shut.

The integrity of the thousands of graphite blocks that make up the reactor core is vital to nuclear safety. They ensure that the reactor can be cooled and safely shut down in an emergency.

But bombardment by intense radiation over decades causes the blocks to start cracking. If they fail, experts say, nuclear fuel could overheat, melt down and leak radioactivity in a major accident.

Both the ONR and EDF told the Sunday Herald that new cracks had been found at Hunterston reactor number three during inspections in recent weeks, but they wouldn’t say how many, or how significant they were.

“We are currently assessing the safety case submitted by EDF after a planned outage identified a number of cracks in the graphite blocks that make up reactor three’s core,” said an ONR spokesman.

“Before we grant permission to EDF to restart reactor three we will require that an adequate safety case justifying further operation has been made. ONR has to formally permission the restart of the reactor.”

The ONR’s decision was still “a number of weeks” away, he added. “We will publish the justification behind our decision once it has been made.”

According to EDF’s website, Hunterston reactor three was originally due back online on March 30 after a “graphite inspection outage”. But this has been repeatedly postponed to April 6, April 19, April 24 and now May 1.

The company confirmed that it had “discovered cracks in the inspections during the current outage”. It promised to report the details to the local site stakeholder group after the reactor was restarted.

“As part of the normal ageing process we expect to see defects occurring in some of the graphite blocks that make up the reactor core of our plants,” said an EDF spokeswoman.

“This phenomenon is understood and is recognised in our operational safety cases which are agreed with the nuclear safety regulator. We have prepared well for this; we have a £100 million graphite research programme.”

She added: “Hunterston B remains safe to operate and will be back online once the current outage is completed. We will, as normal, consult with our regulators before returning the reactor to service.”

Hunterston reactor three, which has been running since 1976, is one of the oldest of its kind. It’s where “graphite defects are most advanced” and hence has more inspections than other reactors, said the EDF spokeswoman.

But Pete Roche, a nuclear critic and consultant in Edinburgh, warned that EDF’s optimism that the reactor will restart could be misplaced. “Cracks could prevent control rods from being inserted causing the nuclear fuel to overheat, potentially resulting in a nuclear accident,” he said.

It was “all a bit of a gamble”, he argued. “Hunterston is already 42 years old - when it was only expected to operate for 30 or 35 years. It is clearly time to say goodbye to reactor three.”

Expert nuclear engineer John Large also suggested that the reactor should be closed down. “The core at Hunterston may now be in such a poor structural state that its collapse during a relatively modest earthquake could result in a nuclear fuel meltdown and significant radioactive release,” he said.

“All that EDF can do is permanently shut Hunterston, there being no alternative means to remedy this very serious situation.”

Professor Paul Bowen, a metallurgist from the University of Birmingham who advises the ONR, thought that the body was likely to insist on more frequent inspections rather than reactor closure. “I’m absolutely confident that the regulator will take a very conservative position,” he said.

According to Rita Holmes, a local resident who chairs the Hunterston site stakeholder group, people were worried. “The local communities are unhappy that the reactor has any cracks, and certainly not happy that one with a growing number of cracks could be allowed to continue generation,” she said.

The Scottish Greens MSP for the west of Scotland, Ross Greer, warned that the discovery of new cracks would cause widespread concern. “EDF and the regulator must explain what has been found, and seek the community's views, before putting this reactor back online,” he said.</s>US President Donald Trump's plans to meet with North Korean leader Kim Jong-un have been welcomed by the Geneva-based International Campaign to Abolish Nuclear Weapons. Photo: AFP

A recent shift in nuclear weapons policies in the United States and Russia, involving upgrades, modernisation and growing arsenals is as dangerous as North Korea's nuclear threat, campaigners warned recently.

Beatrice Fihn, who heads the Geneva-based International Campaign to Abolish Nuclear Weapons (ICAN), hailed an upcoming summit between the United States and North Korean in what Washington hopes will persuade Pyongyang to abandon its nuclear ambitions.

But she said there needed to be more focus on the dangers posed by the United States and other traditional nuclear-armed states, which have recently engaged in "dangerous escalatory activities."

"The new nuclear policies from the United States and Russia that increase the arsenals and create new types of more usable nuclear weapons, these are very dangerous changes," she told journalists in Geneva.

"I think they are equally dangerous as North Korea's nuclear threats," she said.

Five of the world's nine nuclear-armed states -- Britain, China, France, Russia, and the United States -- are parties to the Nuclear Non-Proliferation Treaty (NPT), which will be the subject of a preliminary review in Geneva next week.

But Fihn said they were clearly not respecting their commitments under the treaty, and were all engaged in modernising their arsenals and making nuclear weapons a more central part of their defence strategies.

 

 'Weapons of mass-destruction'

Washington for instance recently decided to upgrade its nuclear weapons arsenal and to complement massive "strategic" bombs with smaller "tactical" weapons, in a move Fihn said would make them easier to use.

She also decried the threatening rhetoric from US President Donald Trump and other leaders of nuclear-armed states.

"We are now seeing some of these states making explicit threats to use weapons of mass-destruction to indiscriminately kill innocent civilians."

Fihn said she welcomed the announcement that Trump would meet with North Korean leader Kim Jong-un within the next two months.

"I think that it is encouraging to see diplomacy rather than threats," she 

 said.

But she cautioned that it was unclear what kind of concessions North Korea would be willing to make.

"I am wondering what the United States will bring to the table in this sort of negotiation," she said, warning it would be "very hard" to convince Pyongyang to abandon its nuclear weapons programme as Washington and others continue to ramp up their arsenals.

She also suggested that Trump's threats to pull out of the Iran nuclear deal could "send a very worrying message to a country like North Korea."

"Why would you make a deal with a country like the United States who doesn't seem to be interested in finding solutions that work for two parties?" she asked.

ICAN won the 2017 Nobel Peace Prize for its efforts to negotiate a treaty prohibiting nuclear weapons.

On Thursday, Fihn accused the nuclear weapons states of using "very serious threats" to pressure countries not to ratify the treaty, including threatening to cancel aid.

The treaty, which since it was voted through last July has been signed by 58 countries and ratified by seven, needs 50 ratifications before it can enter into force.</s>The operator of the Genkai nuclear power plant in southwestern Japan aims to restart another reactor at the complex in late May, according to a plan recently submitted to the government.

The rebooting of the No. 4 unit at the plant in Saga Prefecture after a six-year hiatus will complete Kyushu Electric Power Co's plan to bring four of its reactors online after the country's regulator implemented stricter screening following the Fukushima nuclear disaster in 2011.

According to the plan submitted to the Nuclear Regulation Authority, the company will restart the reactor on May 24 if preparations go smoothly, with commercial operation slated for late June.

Kyushu Electric restarted the No. 3 reactor at the Genkai plant in March. At the company's Sendai complex in Kagoshima Prefecture, two reactors came back online in 2015.

Some local residents have been opposed to the Genkai plant's operation, questioning the validity of safety standards and citing the risk of volcanic eruptions in the region. The Saga District Court rejected in March a request for an injunction to suspend the plant's restart.
Cracks are discovered in the core of Hunterston B nuclear power station in North Ayrshire, Scotland. The Office for Nuclear Regulation is investigating to determine if the reactor is now too dangerous to restart.