Maryland today | “They are playing with a huge fire”


While a United Nations report released today called for a “safety and security protection zone” around Ukraine’s Zaporizhzhia nuclear power plant to prevent a humanitarian and environmental catastrophe amid the Russian occupation of the plant, a University of Maryland expert in nuclear power plant risk assessment said long-term global measures are also urgently needed.

The UN and its International Atomic Energy Agency (IAEA) should begin an international treaty process to ban military operations around nuclear power plants, which generate around 10% of the world’s electricity, said Mohammad Modarres, Nicole Y Kim Eminent Professor in Mechanical Engineering and Director of the Center for Risk and Reliability.

Modarres, who received the American Nuclear Society’s 2019 Tommy Thompson Award for Outstanding Contributions to Nuclear Security, watched months of growing tension as Russian troops dug around the facility, which suffered damage from fighting and retains only a fragile – but critical – connection to the Ukrainian electricity grid. He spoke to Maryland Today about the worst-case scenarios for Zaporizhzhia, as well as why he thinks nuclear power is essential to the future of the world.

We keep hearing “Zaporizhzhia is not Chernobyl”, but what does that mean?It’s a totally different design. Chernobyl used graphite to moderate the reactor, which caught fire and exploded during some abnormal operations. Whatever happened here, it couldn’t be as bad as Chernobyl, in which there was basically a “puff”, and the whole reactor core blew out. This is physically not possible in the Zaporizhzhia plant, which is another Russian design known as VVER-1000 and does not use graphite.

That said, this does not mean that an accident will not happen in Zaporizhzhia, especially under the current conditions.

Can you imagine a chain of events leading to an accident that results in a release of radiation?
It’s entirely possible. The worst case scenario would be for the reactor to operate and lose power from the external grid. It will shut off automatically or manually, but shutting down does not necessarily mean it is safe. It continues to generate a lot of heat from the radioactive core and takes several days to cool down to such an extent that it will not cause significant meltdown in the core; it must therefore be powered externally or by on-site generators during this period. On-site generators can easily be damaged by heavy bombardment.

I’m less concerned about the bombing of the reactor containments, which are very, very strong. They can actually withstand an aircraft impact. The spent fuel pool is also kept inside the containments (although some may be in concrete containers outside the plant yard). But on the outside there’s a lot of ancillary equipment needed to run the plant for air intakes, cooling – so if there’s a bombardment on those types of equipment, it puts the reactor in danger of losing its cooling capacity and melting.

[UMD Poll: Americans Remain Willing to Support Ukraine]

Why is even one of the six reactors still in operation there? Would you start a shutdown if you operated this plant?
Absolutely, I wouldn’t run a reactor under those conditions. This plant provided a high percentage of Ukraine’s electrical power, and now the Russians have apparently diverted it for their own use. I’m no expert in politics or strategy, but in my imagination they can also see it as a protective wall, maybe that’s why they placed military equipment inside the site. They are playing with a huge fire.

In the worst case, what is the magnitude of a possible radiological disaster?
It would be more like what happened in Fukushima, Japan, with some areas to evacuate and decontaminate. If there were a release, the radioactive material could fly away and irradiate mainly people who are not very far from the reactor. Depending on the direction of the wind, it could contaminate nearby areas and increase radiation exposure up to 40 to 50 miles away. There is also a psychological impact which may be more harmful to some people than the radiation itself.

Some commentators have suggested that Russia is using the plant not just for energy, but to threaten Ukraine. Can a nuclear power plant be a weapon?
After 9/11, all nuclear power plants went through a self-examination of exactly this question. Unfortunately, the answer is probably close to a yes, if there is a coordinated effort by terrorists who know about the design and control of the nuclear power plant. But the likelihood of that happening is low, given the backup protocols in place. Nuclear power plants do not explode like a bomb, but if you deprive all cooling, the reactor core melts, and if one manages to open the containment building, which is not so difficult, you can send this radioactivity into the environment and wreak havoc.

What should be done about this?
This is personal, not technical, but I think nuclear power plants should be protected in times of war the same way international war crimes laws limit how you wage war against a population. I think now that this has happened, the IAEA probably needs to lead the development of an international treaty to protect these facilities, which can endanger civilians even in places that are not part of war.

Do we need nuclear power to fight climate change, or is Zaporizhzhia suggesting the risks are too great?
If you think about what climate change could potentially do to humanity, to the health, safety and security of living things, comparatively, the risks from nuclear power plants would be negligible. For example, let’s look at the tsunami-induced Fukushima event. Although the tsunami is not due to climate change, climate-induced flooding on a similar scale is possible. However, the tsunami itself killed nearly 20,000 people in Japan, and the Fukushima nuclear power plants did not do that. [A worker exposed to radiation died of lung cancer officially attributed to the disaster, while several other cancers have been linked to it as well.]

No technology is without risk, not even fully renewable ones such as wind or solar, which can create risks, for example, for the environment during manufacturing, and also cannot completely supply electricity. unbroken base that we need on their own. So I am still very much in favor of expanding the use of nuclear energy on a large scale, but at the same time providing mechanisms, international policies and other barriers against these types of events.

Source link


Comments are closed.