Saturday, March 05, 2022

Russian troops fought for control of a nuclear power plant in Ukraine – a safety expert explains how warfare and nuclear power are a volatile combination

War, in my opinion, is the worst enemy of nuclear safety.


Rafael Mariano Grossi, director general of the International Atomic Energy Agency, points to the training facility hit by Russian artillery at the Zaporizhzhia nuclear power plant. AP Photo/Lisa Leutner



Published: March 4, 2022 

Russian forces have taken control of Europe’s largest nuclear power plant after shelling the Zaporizhzhia facility in the Ukrainian city of Enerhodar.

The overnight assault caused a blaze at the facility, prompting fears over the safety of the plant and evoking painful memories in a country still scarred by the world’s worst nuclear accident, at Chernobyl in 1986. The site of that disaster is also under Russian control as of Feb. 24, 2022.

On March 4, Ukrainian authorities reported to the International Atomic Energy Agency that the fire at Zaporizhzhia had been extinguished and that Ukrainian employees were reportedly operating the plant under Russian orders. But safety concerns remain.

The Conversation asked Najmedin Meshkati, a professor and nuclear safety expert at the University of Southern California, to explain the risks of warfare taking place in and around nuclear power plants.
How safe was the Zaporizhzhia power plant before the Russian attack?

The facility at Zaporizhzhia is the largest nuclear plant in Europe, and one of the largest in the world. It has six pressurized water reactors, which use water to both sustain the fission reaction and cool the reactor. These differ from the reaktor bolshoy moshchnosty kanalny reactors at Chernobyl, which used graphite instead of water to sustain the fission reaction. RBMK reactors are not seen as very safe, and there are only eight remaining in use in the world, all in Russia.

The reactors at Zaporizhzhia are of moderately good design. And the plant has a decent safety record, with a good operating background.

Ukraine authorities tried to keep the war away from the site by asking Russia to observe a 30-kilometer safety buffer. But Russian troops surrounded the facility and then seized it.

REMEMBER THE 'PEACEFUL' USE OF ATOMIC POWER

What are the risks to a nuclear plant in a conflict zone?

Nuclear power plants are built for peacetime operations, not wars.


The worst thing that could happen is if a site is deliberately or accidentally shelled and the containment building – which houses the nuclear reactor – is hit. These containment buildings are not designed or built for deliberate shelling. They are built to withstand a minor internal explosion of, say, a pressurized water pipe. But they are not designed to withstand a huge explosion.

It is not known whether the Russian forces deliberately shelled the Zaporizhzhia plant. It may have been inadvertent, caused by a stray missile. But we do know they wanted to capture the plant.
Tracer rounds and flames can be seen in this video of the fight for control of the nuclear power plant.

If a shell hit the plant’s spent fuel pool – which contains the still-radioactive spent fuel – or if fire spread to the spent fuel pool, it could release radiation. This spent fuel pool isn’t in the containment building, and as such is more vulnerable.

As to the reactors in the containment building, it depends on the weapons being used. The worst-case scenario is that a bunker-buster missile breaches the containment dome – consisting of a thick shell of reinforced concrete on top of the reactor – and explodes. That would badly damage the nuclear reactor and release radiation into the atmosphere. And because of any resulting fire, sending in firefighters would be difficult. It could be another Chernobyl.
What are the concerns going forward?

The biggest worry was not the fire at the facility. That did not affect the containment buildings and has been extinguished.

The safety problems I see now are twofold:


1) Human error

The workers at the facility are now working under incredible stress, reportedly at gunpoint. Stress increases the chance of error and poor performance.

One concern is that the workers will not be allowed to change shifts, meaning longer hours and tiredness. We know that a few days ago at Chernobyl, after the Russians took control of the site, they did not allow employees – who usually work in three shifts – to swap out. Instead, they took some workers hostage and didn’t allow the other workers to attend their shifts.

At Zaporizhzhia we may see the same.

There is a human element in running a nuclear power plant – operators are the first and last layers of defense for the facility and the public. They are the first people to detect any anomaly and to stop any incident. Or if there’s an accident, they will be the first to heroically try to contain it.

2) Power failure


The second problem is that the nuclear plant needs constant electricity, and that is harder to maintain in wartime.

Even if you shut down the reactors, the plant will need off-site power to run the huge cooling system to remove the residual heat in the reactor and bring it to what is called a “cold shutdown.” Water circulation is always needed to make sure the spent fuel doesn’t overheat.

Spent fuel pools also need constant circulation of water to keep them cool. And they need cooling for several years before being put in dry casks. One of the problems in the 2011 Fukushima disaster in Japan was the emergency generators, which replaced lost off-site power, got inundated with water and failed. In situations like that you get “station blackout” – and that is one of the worst things that could happen. It means no electricity to run the cooling system.


Spent nuclear fuel rods are stored at the bottom of this pool, which requires constant circulation. Guillaume Souvant/AFP via Getty Images

In that circumstance, the spent fuel overheats and its zirconium cladding can cause hydrogen bubbles. If you can’t vent these bubbles they will explode, spreading radiation.

If there is a loss of outside power, operators will have to rely on emergency generators. But emergency generators are huge machines – finicky, unreliable gas guzzlers. And you still need cooling waters for the generators themselves.

My biggest worry is that Ukraine suffers from a sustained power grid failure. The likelihood of this increases during a conflict, because pylons may come down under shelling or gas power plants might get damaged and cease to operate. And it is unlikely that Russian troops themselves will have fuel to keep these emergency generators going – they don’t seem to have enough fuel to run their own personnel carriers.


How else does a war affect the safety of nuclear plants?


One of the overarching concerns is that war degrades safety culture, which is crucial in running a plant. I believe that safety culture is analogous to the human body’s immune system, which protects against pathogens and diseases; and because of the pervasive nature of safety culture and its widespread impact, according to psychologist James Reason, “it can affect all elements in a system for good or ill.”

It is incumbent upon the leadership of the plant to strive for immunizing, protecting, maintaining and nurturing the healthy safety culture of the nuclear plant.

War adversely affects the safety culture in a number of ways. Operators are stressed and fatigued and may be scared to death to speak out if something is going wrong. Then there is the maintenance of a plant, which may be compromised by lack of staff or unavailability of spare parts. Governance, regulation and oversight – all crucial for the safe running of a nuclear industry – are also disrupted, as is local infrastructure, such as the capability of local firefighters. In normal times you might have been able to extinguish the fire at Zaporizhzhia in five minutes. But in war, everything is harder.
So what can be done to better protect Ukraine’s nuclear power plants?

This is an unprecedented and volatile situation. The only solution is a no-fight zone around nuclear plants. War, in my opinion, is the worst enemy of nuclear safety.

Author
Najmedin Meshkati
Professor of Engineering and International Relations, University of Southern California
Disclosure statement
Najmedin Meshkati received research funding from the US Nuclear Regulatory Commission NRC in mid-1990s.


Ukraine power plant videos show staff imploring Russian troops to ‘stop firing’

Loudspeaker can be heard warning soldiers outside the Zaporizhzhia plant — the biggest nuclear facility in Europe — that they’re ‘endangering safety of the entire world’
Today,

Workers at the Zaporizhzhia nuclear power plant pleading with Russian soldiers to stop firing at the facility, on March 4, 2022. (Screenshot/Twitter)

Videos released Saturday showed staff at an atomic power plant in Ukraine pleading with invading Russian troops to stop firing at the complex, an incident that sparked fury from Ukrainian and Western officials.

The videos appeared to show one of the operational rooms inside the Zaporizhzhia nuclear plant, Europe’s largest, with a loudspeaker heard warning the Russian soldiers outside.

“Stop firing at the nuclear facility,” a voice said. “Immediately stop firing. You are endangering the safety of the entire world. The operation of a crucial part of Zaporizhzhia’s plant could be damaged. We will not be able to restore it.”



The six reactors at Zaporizhzhia, which can power four million homes, appeared undamaged by the fighting and a fire that broke out in a training facility on Friday.

As a precautionary measure, Ukrainian authorities were distributing iodine tablets to residents living near the Zaporizhzhia nuclear reactor.

The New York Times said a fire that erupted at the site blazed some 1500 feet (500 meters) from the site’s nearest reactor.


Rafael Grossi, director-general of the International Atomic Energy Agency (IAEA), said he was prepared to travel to Ukraine to ensure the security of the country’s nuclear facilities.

He told the Security Council that a “projectile” hit a building adjacent to a block of six reactors at the Zaporizhzhia plant, sparking a fire that didn’t affect its operation, although he stressed there is nothing normal when military forces are in charge of the site.

Grossi has repeatedly stressed that any military or other action that could threaten the safety or security of Ukraine’s nuclear power plants must be avoided.

“I remain gravely concerned about the deteriorating situation in Ukraine, especially about the country’s nuclear power plants, which must be able to continue operating without any safety or security threats,” he said.

IAEA Director General Rafael Mariano Grossi speaks at a press conference about the situation at the Zaporizhzhia Nuclear Power Plant in Ukraine in Vienna, Austria, on Friday, March 4, 2022. (AP Photo/Lisa Leutner)

“Any accident caused as a result of the military conflict could have extremely serious consequences for people and the environment, in Ukraine and beyond.”

Ukrainian President Volodymyr Zelensky said during a call with US senators that Russian forces have now seized two Ukrainian nuclear power plants and are advancing toward a third — the Yuzhnoukrainsk nuclear power plant, located 120 kilometers (75 miles) north of Mykolaiv, one of several cities the Russians were trying to keep encircled.

Ukraine has four nuclear plants with a total of 15 reactors.

What happened in Ukraine nuclear plant? West says Russia attacked, Russia blames Ukraine

The head of the UN nuclear agency reaffirmed that no reactors were hit


By PTI Updated: March 05, 2022 
An image from the Zaporizhzhia Nuclear Authority shows multiple blasts from Russian shelling | AFP

The United States and its allies have accused Russia of attacking Ukraine's largest nuclear power plant and putting the lives of millions of Europeans at risk of radiation fallout, but Russia claimed a "Ukrainian sabotage group was responsible for setting fire to a nearby training facility.

At an emergency meeting of the UN Security Council after photos of a burning building sent shock waves around the world of a possible nuclear disaster on Friday, the head of the UN nuclear agency reaffirmed that no reactors were hit and the Zaporizhzhia plant in the southeastern city of Enerhodar was operating normally.

But International Atomic Energy Agency Director-General Rafael Mariano Grossi didn't say who was responsible for firing a projectile that hit a building adjacent to a block of six reactors at the plant sparking a fire.

He said the IAEA was informed a few days ago by Russia that its forces were moving to take control of the plant.

Their advance toward its perimeter was met with opposition and some group of civilians attacking the access to the plant, he said, and early Friday the IAEA got information that a projectile had impacted a building adjacent to the block of reactors six of them.

For Ukraine and Western countries and allies on the Security Council there was no question that Russia was responsible for firing the projectile. The emergency meeting was called by the US, UK, France, Norway, Ireland, and Albania.

Britain's UN Ambassador Barbara Woodward said Russia's reckless attack marked the first time that any country has attacked a fuelled and functioning nuclear power plant.

In doing so, she said, it had breached international law and the Geneva Convention on the conduct of war which states that dams, dykes, and nuclear electrical generating stations, shall not be made the object of attack.

US Ambassador Linda Thomas-Greenfield opened her remarks saying: By the grace of God, the world narrowly averted a nuclear catastrophe last night.

She called Russia's attack incredibly reckless and dangerous, saying it threatened the safety of civilians across Russia, Ukraine and Europe.

Dr Alex Rosen, a pediatrician and vice-president of the German affiliate of the Nobel prize-winning group International Physicians for the Prevention of Nuclear War, said the attack clearly shows the danger of fighting war in a nuclear state.

Had the projectile hit a spent fuel pond at the Zaporizhzhia nuclear plant or one of its six reactors, the prevalent winds Friday morning could have spread radioactive fallout toward the southeast, across the Azov Sea straight into Russia, engulfing the city of Rostov and continuing toward Georgia, Rosen said in an interview.

Russia's UN ambassador Vassily Nebenzia rejected claims that its military forces attacked the plant as simply untrue and part of an unprecedented campaign of lies and disinformation against Russia.

He claimed Russia took control of Enerhodar and the Zaporizhzhia on February 28 and reached agreement with the plant's management for the Russian military to guard the facility to ensure its security to prevent the Ukrainian nationalist or other terrorist forces from taking advantage of the current situation to organise a nuclear provocation.

According to the Russian Ministry of Defence, he said, a Russian mobile patrol in the area adjacent to the plant on Thursday night was attacked by a Ukrainian sabotage group with heavy small arms fire from the windows of several floors of a training complex just outside the nuclear plant in order to provoke return fire.

The Russians returned fire and suppressed their fire, he said, and as they were leaving, the Ukrainian sabotage group set fire to the training facility.

For Russia and Belarus which as neighbours lived through the 1986 Chernobyl nuclear disaster, Nebenzia said, maintaining a normal radiation situation throughout Ukraine is important. And he again blamed Ukrainian nationalists for the incident at the plant and accused the West of attempting to blow it into a global scandal.

Ukraine's UN Ambassador Sergiy Kyslytsya accused Russia of committing an act of nuclear terrorism by shelling the nuclear power plant and dismissed as lies Nebenzia's claim that a Ukrainian sabotage group was responsible for setting fire to a training facility at the plant.

He said the Russian ambassador may not be properly informed by his government.

Kyslytsya expressed disappointment that the IAEA's Grossi did not include any mention of the attacking side.

We demand clear and decisive action from the IAEA, he said.

The international community must respond adequately to the actions of the Russian Federation, which could lead to an unprecedented nuclear catastrophe.

The Zaporizhzhia plant is currently under control of the Russian armed forces, Kyslytsya said. While there have been no changes in radiation levels, Kyslytsya said several buildings are damaged and the telephone connection to the plant is disrupted and not available at the moment. 

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