What could be consequences of blowing up ZNPP

Author: Тетяна Галковська

When you flip through the pages of the media, read the statements of the president, the head of the GUR and the heads of the Ministry of Health and the IAEA, you get the exact opposite picture - from complete apocalypse to "you won’t feel it at all". So will we feel it or not? If the explosion does happen, what will it be like, for example, compared to Chernobyl, whose anniversary we commemorate every year? Should we prepare for it somehow or not?

Prevention is not required

Anatoliy Chumak, professor and director of the Institute of Clinical Radiology, is one of those who believe that the explosion will have no impact on human health or the environment in most of Ukraine.

"In Chornobyl, an operating reactor exploded and the power of the explosion was extremely high. There is no such power at Zaporizhzhya NPP now. Most of the units, except for the fifth, are in a state of cold shutdown. That is, there is no nuclear reaction there. And only one fifth is left on purpose so that it can be overclocked at any time and create an emergency. But even if it is blown up, there will be no such explosive force," says Anatolii Andriiovych.

Professor Chumak also sees no need for preventive measures for the population living outside the 50-km zone.

"What kind of prevention can there be? The well-known potassium iodide is used to protect against radioactive iodine. But it will not be available at ZNPP, and there is no need to take pills, especially in advance as a preventive measure. Only when there are reports of radioactive iodine in the air. Therefore, do not stock up. Moreover, 'preventive' intake is a health hazard, as it can lead to nodular goitre and other diseases," says Anatoliy Chumak.

The only prevention he advises is to eat as varied a diet as possible, including vegetables, fruits and herbs, to maintain a good sleep schedule and to concentrate on the positive. Of course, this is very difficult in our conditions, but, in his opinion, it is very important both for preventing mental problems and for preventing diseases.

No one will be satisfied

Nevertheless, not everyone believes that there is no particular threat and that we can calm down.

Nuclear safety expert Olha Kosharna is convinced that despite IAEA Director General Rafael Grossi's statements that "the main safety functions of the facility will not be significantly affected", there is a threat. In her opinion, mining of the main elements of the ZNPP reactor cooling system poses a direct threat to the entire nuclear power plant.

As Olha Kosharna explains, while five power units are kept in cold shutdown, the sixth is in hot shutdown, and it can easily be brought to the minimum controlled power. Then a chain reaction can start and the composition of radionuclides changes, in particular, iodine-131, which is dangerous in a radiation accident, is produced. Cooling water is needed not only to cool the reactor in a hot shutdown, but also for all six reactors and 6 spent fuel pools. Without cooling in cold-shutdown reactors, a severe accident with a reactor core meltdown will begin in 8 days, and in hot-shutdown reactors - in 27 hours. This could result in an explosion similar to the one at Fukushima with radiation consequences.

"Of course, it will be smaller than the one in Fukushima, but no one will be shortchanged," concludes Olha Kosharna.

The expert also says that no iodine prophylaxis is needed because there is no radiative iodine in a cold reactor. But if Unit 5 is brought up to minimum controlled power, it will already appear and spread over a distance that depends on the wind direction, temperature, and precipitation at that moment. She advises to have a respirator with a red valve, which we wore during the Covid epidemic. And in the event of a reactor explosion, follow the Ministry of Health's announcement to start iodine prophylaxis, stay at home, close all cracks in the windows, drink bottled water, take frequent showers and do wet cleaning in the apartment. And wait for the signal when the threat is over.

It won't fly to Kyiv

Ivan Kovalets, head of the Department of Environmental Informatics at the Institute of Mathematical Machines and Systems of the National Academy of Sciences of Ukraine, has worked out 150 different meteorological scenarios that could develop at ZNPP in the event of an explosion. In an interview with Censor.NET, he explained his calculations:

- The population living nearby, within a radius of approximately 20 km in the direction of the wind, will be most affected. The consequences for them may be more severe than for remote settlements, but much less severe than if the plant were operating. Evacuation of the population will be required in this area.

For Kyiv, for example, the difference is smaller, because less short-lived radionuclides travel over such distances, as they partially decay earlier. Long-lived radionuclides, such as cesium and strontium, pose the greatest danger to remote settlements up to about 500 kilometres away. They are still present in the reactor and can be released into the environment and harm people's health. The fact that the reactors are cold still reduces the consequences for the 30-kilometre zone.

- Possible developments at ZNPP are now being compared to the Fukushima accident.

- Even in the worst-case scenario, there will be no accident of the scale of the one in Fukushima, Japan. Although this could also be a Class 7 accident, the equivalent emissions in the scenario under consideration are about one and a half times lower.

- Which areas will be affected by the pollution and will not be able to conduct agricultural activities?

- In the worst case scenario, it could be a continuous strip 10 km wide and 170 km long. But individual spots with high densities of surface pollution can also form over longer distances, say 300 or even 500 km.

- Depending on the meteorological situation, for example, rain, wind, right? I remember when the Chernobyl accident happened, the Swedes were the first to sound the alarm, as they noticed an increase in radiation levels.

- These are not comparable things - the increase in radiation levels recorded by monitoring and the one that leads to medical consequences. Let's start with this. There is an international standard that defines the annual dose that the population can receive. It is one millisievert per year. That is, all activities of enterprises should be designed in such a way that the population does not receive more than one millisievert.

According to my scenario, at a distance of up to 550 km, you can get not 1, but even 10 millisieverts. But this is not a catastrophe in the sense that we need to take shelter or relocate in this area. These are doses that will have consequences (growth of certain diseases, etc.) comparable to those of major economic crises. I am not an epidemiologist, and this is not a professional statement. But, as far as I know, after Chornobyl, epidemiologists tried to identify the consequences of the accident for the population living outside the Exclusion Zone, but found less than expected.

- Why?

- The consequences of the collapse of the Soviet Union were stronger. And this is not a joke. I was interested in the data. In '92, the increase in male mortality from coronary heart disease was comparable in numbers to the effects of covid, for example, in Sweden.

- Wow!

- In 1992, 1993 and 1994, post-Soviet countries recorded a spike in male mortality. And, as far as I know, the only long-term consequence of the Chernobyl accident that epidemiologists have been able to identify among the population living outside the Chernobyl zone in the affected areas is an increase in thyroid cancer in children due to the consumption of contaminated food. Among adults, no statistically significant effects were found. That is, the doses we are talking about violate the established hygiene standards. But if we talk about the scale of the consequences, these are so-called random (stochastic) effects.

That is, there will be some increase in the number of cardiovascular diseases, some increase in the number of cancers. But today, other factors also cause an increase in various diseases. Compared to all this, the consequences of the explosion at ZNPP at long distances, more than 300 km, may not even be detected. Just as they were not detected after Chernobyl. That is why the official UN estimate of the number of fatalities from Chornobyl is approximately 4,000.

- Liquidators?

- Not only that, it is the sum of all the victims.

- Under what conditions is evacuation necessary?

- The lower limit of justification for resettlement is 200 milliards, not 10 or 1. But the upper limit of justification, when it is necessary to resettle, is 1,000 millisieverts. According to my calculations, this corresponds to a 10-km zone.

* * *

Will the occupiers dare to commit a terrorist attack on the ZNPP? Today, political scientists, politicians, and experts are giving their versions. But, as practice has shown, the enemy often acts illogically, even harming itself. Now, managers, specialists and military personnel are leaving the plant. Is this a manoeuvre or a real preparation for blowing up the plant? Let's see.

Tatiana Galkovska, Censor.NET