LEILA FADEL, HOST:
Russia has occupied Europe's biggest nuclear power plant, the Zaporizhzhia facility in Ukraine, since shortly after the invasion began. Now Western intelligence officials say Russian forces are launching attacks on Ukrainian forces from the facility, knowing that the Ukrainians wouldn't risk returning fire. To learn more about what's at risk, we've called on Ukrainian nuclear scientist Mariana Budjeryn at the Harvard Kennedy School's Belfer Center.
Good morning, Mariana. Thank you for being back on the program.
MARIANA BUDJERYN: Good morning. It's nice to be with you.
FADEL: So we spoke at the very beginning of this invasion about concerns about the safety and security of the Zaporizhzhia plant. But today, hearing these reports that Russian forces are launching attacks from the plant, how concerned are you now about the safety and security?
BUDJERYN: Well, in a word, I'm extremely concerned, and so are my colleagues who are watching these events develop. It is rather clear that the Russian invading force is using this facility as part of its military strategy, sort of as a military base. As you mentioned, there's armor and heavy equipment and ground fire that has been deployed to the station. There were reports of shelling that has originated at that station and is targeted at the nearby town of Nikopol, which is under Ukrainian control. And those, of course - cheap shots, right? You can't turn around and take out...
FADEL: And shoot back.
BUDJERYN: ...That - and shoot back. So that, of course, disadvantages Ukrainian forces to - a great deal. And this is sort of this nuclear fortress, as it were, that Russians have built up. And all of that is on actively operating nuclear power plant. There are cruise missiles flying low. There's explosions at the station. We really do not have access to very good quality information, and we cannot corroborate some of these reports. So we have to compute the possible motivations for any one of the sides to shell the Zaporizhzhia station. But it certainly looks like Russians have a lot more motivation or incentive to cause some kind of trouble there than Ukrainians do.
FADEL: Now, you've talked about how there's concerns, so you don't shoot back. But there's munitions coming from inside the plant. I mean, what's the risk of a disaster here? How far could the fallout spread, and what would a radioactive cloud do to the region?
BUDJERYN: Well, the most - some of the most vulnerable systems there are the power lines that lead to the station. So, of course, nuclear power station produces electricity, but its safe operation very much relies on the stable supply of offsite electricity. And in the recent days, we have heard that three out of four high-voltage power lines have been damaged. So the power station now operates on this one voltage line. And what happens - basically that this electricity feeds some of the very crucial cooling systems that keep a nuclear reactor operating at a certain temperature, as it were. It pumps water in and takes heated water out of the reactor in order to make sure that the core operates within these safe limits. This is also true for the spent-fuel pools.
So some of this fuel that's taken out of the reactor - it needs to cool for several years, actually, in these pools outside of the reactor. And that fuel is still very active and still very hot and also relies very much on the cooling system. If the supply of electricity and the supply of water - if these pumps are no longer operating, then the water basically evaporates. The fuel heats up. It can catch on fire in spent-fuel pools. If you have fire, you have smoke. That stuff goes into the atmosphere and then gets carried by the prevailing winds in whichever direction.
There are, of course, backup safety systems at every nuclear power plant. There are diesel-powered generators. But those are not designed to run the station for a long time. There's a limited supply of fuel. And, of course, you know, the supply lines to this power stations - to Zaporizhzhia - are entirely under Russian control. So we really can't rely on this military administration, these people who do not know - who know very little how to safely operate nuclear power plants and what can go wrong, to provide this kind of backup.
FADEL: So if these safety mechanisms fail, if there is a disaster, this could be a Chernobyl or a Fukushima situation in Ukraine.
BUDJERYN: Indeed. And even more so - what we've learned, especially with Fukushima, is the value of timely response to any kind of nuclear accident and how that - the mitigation of consequences can actually ease - you know, ease the suffering and the damage...
FADEL: Right.
BUDJERYN: ...That is done by a nuclear accident on that scale. And here, there really isn't a guarantee. In fact, we can safely assume that there won't be a reliable way to bring relief supplies, to bring mitigation workers, to supply the necessary parts, to evacuate people...
FADEL: Right.
BUDJERYN: ...Because, again, this facility is trapped inside an active war zone.
FADEL: An unprecedented situation - the head of Ukraine's state nuclear power firm told Reuters that he believes the Russians want to sever the plant from the Ukrainian power grid. If that happens, what then?
BUDJERYN: Well, it might be that the recent developments - the recent shelling and the damage to power lines - in some way, a part of this Russian plan to switch Zaporizhzhia nuclear power plant to the Russian grid, basically to steal. This is how you steal a power plant. And what you mentioned - the president of Ukraine's nuclear operator, Petro Kotin - he indeed described this plan in some detail yesterday. Again, we have no way to corroborate whether - you know, how reliable is this information and this plan. But apparently the plan is to switch off - to disconnect the power plant from the Ukrainian grid.
FADEL: Mariana Budjeryn from the Harvard Kennedy School's Belfer Center. Thank you.
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