OUR nuclear power plant her Zaporozhye on South Ukraine it has been bombed several times in recent days, raising the possibility of a serious accident just 500 kilometers from the site of the world’s worst nuclear accident, the 1986 Chernobyl disaster.

General Secretary United StatesAntónio Guterres called for the demilitarization of the area around the nuclear power plant, which is also the largest in Europe.

What are the risks?

The Zaporozhye NPP has six Soviet-designed reactors containing uranium-235.

The biggest risk comes from reduced water supply.

Pressurized water is used to remove heat from the reactor and slow down the neutrons so that the uranium-235 can continue its chain reaction.

If the water supply is cut off and auxiliary systems such as diesel generators fail to cool the reactor in the event of an attack, the nuclear reaction will slow down and the reactor will begin to heat up very quickly.

At such high temperatures, hydrogen can be released, causing the reactor to melt.

However, experts say the building that houses the reactors is designed to contain radioactivity and withstand high impact, meaning the risk of a major leak is still limited.

“I do not think that this building will be breached even if a bomb accidentally hits it, and it is even less likely that the reactor itself will be damaged in such a case. This means the radioactive materials are well protected,” says Mark Wenman of Imperial College London.

What about spent nuclear fuel?

In addition to reactors, facilities where SNF is collected have SNF storage facilities. Spent fuel tanks are used to cool spent nuclear fuel.

“These are big tanks with uranium fuel rods. Their temperature is very high depending on how long they are there,” says Keith Brown, an environmental historian at the Massachusetts Institute of Technology.

“If fresh water does not reach them, then [ήδη υπάρχον] he will evaporate. As soon as the water evaporates, then the zirconium shell will heat up and catch fire, and then everything will be complicated – the fire from radioactive uranium will very much resemble the Chernobyl case, ”he adds, by the way.

A release of hydrogen from a spent nuclear fuel tank caused an explosion at the 4th Fukushima reactor in 2011.

What will happen in case of an accident?

After the invasion of Ukraine on February 24, Russian troops took control of the plant in early March.

Ukrainian workers at the nuclear power plant continue to operate it, but the facility is guarded by special Russian military units and advised by Russian nuclear scientists. The IAEA has warned that staff are working under extremely stressful conditions.

If there were a nuclear accident, Brown said, it remains unclear who would have handled it in the midst of a war.

“We don’t know what will happen in the event of a wartime nuclear emergency,” he added. “In 1986, everything worked perfectly in the Soviet Union, so tens of thousands of people, equipment and vehicles were able to mobilize in the region.”

“Who would take on such a venture today?”

^{Source: Reuters.}