The presence of new cracks in a reactor at the Hunterston B nuclear reactor on Scotland's west coast raises important safety questions about several other aging reactors in the UK, an independent nuclear expert told DW on Sunday.

The plant's Reactor 3 was taken offline in March after Britain's Office for Nuclear Regulation (ONR) was informed about keyway root cracks in the core's graphite bricks.

Read more: German city of Aachen offers iodine tablets amid nuclear fears

Last week, operator EDF Energy said it would extend the shutdown to November to allow for additional safety checks after it discovered more new cracks. But the operator insists it will ultimately be able to restart the reactor — something it can only do with the ONR's permission.

"I'm absolutely positive they won't be able to do that," independent nuclear engineer John Large told DW.

EDF Energy has to close down a nuclear reactor at the Hunterston B Nuclear Power Station in Scotland after new cracks were discovered

Greater chances of nuclear meltdown

The graphite blocks in the reactor's core ensure it can be cooled and safely shutdown in a nuclear emergency. If they are weakened in any way, there's a chance an earthquake or modest tremor could trigger a nuclear meltdown and radioactive release, Large told DW.

"EDF can't do anything physically to resolve the situation. The bricks were never designed to be replaced. In fact, it's entirely inaccessible inside the reactor's core."

Read more: Nuclear power faces uncertain future in Europe

Hunterston's Reactor 3 has been generating power since 1976 and was due to go offline in 2025.

"While Hunterston B Reactor 3 could return to operation from the current outage, it will remain offline while the company works with the regulator to ensure that the longer term safety case reflects the findings of the recent inspections and includes the results obtained from other analysis and modelling," EDF said last week.

Does nuclear power have a future? Deadly disaster The worst nuclear disaster of all time, the explosion at Chernobyl nuclear plant in Ukraine released massive amounts of radiation into the atmosphere. Areas close to the plant - in Ukraine, Belarus and Russia - were heavily contaminated. Heightened levels of radiation were also measured across most of Europe. The "exclusion zone" around Chernobyl remains off-limits to human habitation today.

Does nuclear power have a future? It happens again After a magnitude-9 earthquake and consequent tsunami, three nuclear reactors at Fukushima power plant in Japan went into meltdown in March 2011. There were also four hydrogen explosions. The accident released 500 times as much radioactive cesium-137 as the nuclear bomb dropped on Hiroshima in 1945. The clean-up is expected to take decades.

Does nuclear power have a future? Sickening impact After Chernobyl, thousands of people developed cancer. In Japan too, the heavily contaminated region of Fukushima, where 200,000 people lost their homes, saw cases of the disease escalate. The number of children with thyroid cancer there is 20 times higher than other regions.

Does nuclear power have a future? Rallying against nuclear power Chernobyl fueled public opposition to nuclear power, particularly in Europe. The same happened after Fukushima. Before the Japanese disaster, the country relied on nuclear for 30 percent of its power. That has fallen to 1 percent. The government wants to continue producing nuclear power and plans to reinstall some reactors. But affected regions have successfully pushed back those plans.

Does nuclear power have a future? Nuclear industry in crisis Today, the nuclear power sector is deep in economic crisis. In Japan, the United States and France, nuclear power plants run at a loss, and construction projects for new reactors have been postponed.

Does nuclear power have a future? New-build set-backs France had high hopes for its newest nuclear reactors - called pressurized water reactors (PWRs). This technology was supposed to be safe, and the Flamanville power plant was due to be switched on in 2012. Due to security issues, that's been pushed back to 2018 at the earliest. The project will cost more than 10 billion euros - three times the original budget.

Does nuclear power have a future? Great Britain plans new reactors For years, the UK has been planning to build two new PWR reactors at Hinkley Point. Costs are estimated at 33 billion euros and groundbreaking is slated for 2019. But doubts are growing over its economic viability. The electricity it produces will be much pricier than solar or wind power, and will need subsidies to compete in the market.

Does nuclear power have a future? Aging reactors up for grabs Nuclear power plants used to be lucrative. But now, many are old and frail. Repair costs often mean they cannot turn a profit. Swiss energy corporation Alpiq recently tried to give away two of its old plants, 33 and 38 years old, to French energy company EDF - which declined the offer.

Does nuclear power have a future? Disasters abroad prompt German phase-out Three decades ago, the Chernobyl disaster galvanized Germany's anti-nuclear movement, which is often cited as the roots of the country's energy transition. In 2002, Germany passed a law that would have seen the last reactor shut down in 2022. The plan was later scrapped by Angela Merkel's government. But after Fukushima, Merkel quickly reversed her decision and the phase-out was back on track.

Does nuclear power have a future? Switching them off So far, nine of Germany's reactors have gone offline, with eight more to follow by 2022. To finance the costs of nuclear waste disposal, plant operators must pay 23.6 billion euros into a federal fund. The operators themselves are responsible for the similarly costly process of dismantling the plants, which will take decades to complete.

Does nuclear power have a future? Growing fear of accidents Across the EU and Switzerland 132 nuclear reactors are still online. They were designed to operate for 30 to 35 years - their average age is now 32 years. Malfunctions and security issues are frequently detected and protestors are increasingly calling for plants to be shut down.

Does nuclear power have a future? China pushes on with nuclear No new nuclear power plants have been built in the EU, Japan or Russia since the Fukushima disaster in 2011. China remains committed to nuclear, partly to replace coal-based power. But the country is also upping investment in wind and solar. Author: Gero Rueter (sst,jf)



'Gambling with public safety'

The reactor is one of the oldest of its kind. Hunterston Reactor 4, which is 18 months younger, is still in operation. Six other aging plants in the UK are also vulnerable, says Large.

"They all have the same aging problem," he said. "They were all built in the 70s and 80s, and that means that all of them have reached this threshold limit when the key-route cracking becomes a problem."

Edinburgh-based nuclear critic and consultant Pete Roche, told Scotland's Sunday Herald that extending the lives of old reactors was "gambling with public safety."

Read more: Nuclear waste: Where to store it for eternity?

The Herald quoted the Scottish government as saying: "We expect ONR will exercise its duties diligently to ensure the nuclear industry controls its hazards effectively and maintains the highest nuclear safety and security standards."

In 2014, two of EDF's British plants, Heysham 1 and Hartlepool, were taken offline after a crack was found on a boiler spine. Also in Belgium, production was stopped at two nuclear reactors in 2012 after inspections found tiny cracks in core tanks.

Chernobyl: The people who've stayed The contagious optimism of Baba Gania Baba Gania (left) is 86 years old. She survived her husband who died a decade ago. For the past 25 years, Gania has taken care of her mentally disabled sister Sonya (right). "I am not afraid of radiation. I boil the mushrooms till all the radiation is gone!" she says proudly. Photographer Alina Rudya visited her several times over the past years: "She is the warmest and kindest person I know."

Chernobyl: The people who've stayed Hastily left: Abandoned houses in the Zone Gania and her sister live in Kupuvate, a village in the 30-kilometer (19-mile) exclusion zone around the ruins of the Chernobyl nuclear power plant. After the accident in April 1986, hundreds of thousands of residents in the area were hastily evacuated. Most houses in Kupovate remained abandoned. Gania is using this one in the neighborhood to store her and her sister’s coffins.

Chernobyl: The people who've stayed Where the dead return "The cemetery of Kupuvate looks like any other village cemetery in Ukraine," photographer Alina Rudya reports. "Many people who are buried here were evacuated and spent their lives outside of the nuclear radiated zone, only to return after their death."

Chernobyl: The people who've stayed The last wish of Baba Marusia The returnees look after the remains of their family — like Baba Marusia, who came to clean her mother's grave. Her daughter lives in Kyiv, sharing a one-bedroom apartment with her husband and two children. "I am happy I stayed here, though. It is my homeland. That is where I want to be buried." And she adds: "But next to my mother, not my husband."

Chernobyl: The people who've stayed Samosely: Those who returned to stay Galyna Ivanivna is another of the few self-settlers in the zone, the so-called samosely. "My life flew by in a blink of an eye. I am 82 years old right now and it is as if I’ve never lived. When I was younger, I wanted to travel the world. I remember dreaming of having a free ticket which would take me around the globe. But I never managed to go further than Kyiv."

Chernobyl: The people who've stayed Living in a world of his own Ivan Ivanovych and his wife were also among the few hundred who decided to move back to the contaminated area in the 80s. Ivan has become somewhat of a local star among the tourists visiting the area. His wife died some years ago — "But every time I visit him, he tells me it happened 'last year.' He is full of stories, which vary between truth and imagination," says the photographer.

Chernobyl: The people who've stayed Witnesses of the past One week before the 32nd anniversary of the Chernobyl disaster on April 26, Ukranian photographer Alina Rudya visited the village of Opachichi. She found one old woman who still lives there, but most of the other self-settlers have died. Empty houses have been left open with old pictures, letters, Ukrainian embroidered towels and furniture silently serving witness.

Chernobyl: The people who've stayed Slowly saying goodbye Marusia is watching over her husband Ivan, who recently had a stroke and suffers from dementia. "Sometimes he wakes up at night and goes searching for his tractor. He worked on one for 42 years." She herself is concerned about dying slowly. "I don’t want to be a burden to my kids and grandkids."

Chernobyl: The people who've stayed Providing for death Before Ivan fell ill, he built two coffins to prepare for both his death and the death of his wife. They are stored in a shed next to the house. "The lower one is for me and the upper one for my old man," Marusia explains.

Chernobyl: The people who've stayed The last self-settlers Only a few "samosely" are still living in the exclusion zone. Alina Rudya, who was herself born near Chernobyl, has returned several times and photographed them for her long-term project, which she is planning to publish as a book. "Visiting abandoned villages feels more and more sad each time. Every time I come, someone has died, since almost all of the self-settlers are over 70 years old." Author: Christine Bayer, Alina Rudya



Each evening at 1830 UTC, DW's editors send out a selection of the day's hard news and quality feature journalism. You can sign up to receive it directly here.