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243: Chernobyl Part 1

HBO’s Chernobyl miniseries tells the story of the worst nuclear disaster in history. Today, we’ll be looking at the first episode in the miniseries called 1:23:45.

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Note: This transcript is automatically generated. There will be mistakes, so please don’t use them for quotes. It is provided for reference use to find things better in the audio.

There’s some text on screen that gives us a time and place.

Moscow. April 26, 1988. And while it’s not included in the text, the camera shot behind the text is a clock giving us the exact time. It’s 1:10 and since it’s dark through the apartment window, we can assume that’s 1:10 AM.

The apartment belongs to Valery Legasov, who is played by Jared Harris. He’s just poured himself a drink and is listening to a cassette tape. On the recording, his own voice talks about how stories only want to know who is to blame. And, in this story, the best choice was Anatoly Dyatlov because he ran the room that night and he didn’t have friends—not important enough ones, at least. So, he’ll serve ten years in a prison labor camp.

Legasov stops the playback. Then, he hits the record button and continues the story where it left off. This time he’s speaking into the cassette tape.

He ends the recording by saying he’s given everything he knows. They’ll deny it, of course. They always do. He stops the tape and puts it with others—five others, for a total of six. Each tape is labeled with a number 1 through 6. He wraps them all in newspaper and then walks outside to hide the bundle in a grate nearby. He also takes out his cat’s litter so it seems like he’s just doing chores to the man in the car obviously watching his house from the street. We can assume it’s a KGB agent, although the series never really tells us for sure. It seems to work because the man stays in the car.

With that done, Legasov heads back inside.

A few minutes later, we find out why the episode has the title 1:23:45. It’s the time. Looking at his watch as the seconds tick closer to 1:23 AM and 45 seconds, that is exactly the moment when Legasov climbs up on furniture in his apartment and hangs himself.

Then, the next shot we see transports us back in time exactly two years and one minute earlier. Then, of course, we see the explosion—which we’ll get to in a moment, but before we do, we can tell from how the series sets up this opening sequence with the timing that it’s saying Valery Legasov committed suicide exactly two years to the second after the Chernobyl accident.

There’s a lot of what we saw in the opening sequence that is true, but the biggest inaccurate thing is the idea that Legasov committed suicide to coincide with the two-year anniversary of the explosion down to the second. That is simply not true.

It is true that Legasov committed suicide near the two-year anniversary of the explosion, but not necessarily down to the exact second of the explosion itself. In fact, as we’ll learn about in more depth later on, there was more than one explosion.

The truth is that Valery Legasov hung himself in his apartment on April 27th, 1988—that’s two years and one day after the explosion.

Or, maybe he didn’t intend for it to be timed perfectly with the explosion itself, but maybe it was because the next day, on the 28th of April, 1988, that’s when he was scheduled to release the outcomes of the investigation into the causes of the disaster.

There are also some discrepancies to exactly where Legasov hung himself. Some sources say it was in his Moscow apartment like we see in the series. Some say it was in the stairwell of his apartment complex.

He didn’t leave a note, so there’s a lot of speculation as to his reasons—and my own speculation is that it’s too close to the anniversary of the explosion to be a coincidence.

What he did leave were tapes of his memories that he’d been recording since he became involved in the Chernobyl disaster. Some also point to something we don’t see in the HBO miniseries at all: It’s not the first time he attempted suicide.

For that, we’d have to go back to the summer of 1987.

But, that attempt didn’t succeed and for a while Legasov threw himself back into his work. Meanwhile, his health continued to fail due to the radiation he was exposed to and on the two-year anniversary of the Chernobyl disaster, a proposal he had to launch a new committee on chemical research was rejected. That same day, he gathered all his personal belongings from his office. The next day, he was found dead at his apartment.

While ostracized for his involvement during his life, in the aftermath of his apparent suicide, Legasov’s tapes couldn’t be denied. They were circulated in the scientific community and eventually extracts of them were published the following month, May of 1988. Nearly ten years later, on September 20th, 1996, President Boris Yeltsin, posthumously gave Valery Legasov the title of Hero of the Russian Federation—Russia’s highest honorary title.

But, alas, even though the HBO miniseries starts at the end, we don’t want to get too far ahead ourselves in the story.

Let’s go back into the timeline of the first episode now. There’s text on the screen that tells us we’re two years and one minute before Valery Legasov’s suicide.

Of course, as we learned, the series wasn’t quite right with the timing of Legasov’s suicide, but if we were to follow their timeline then two years and one minute earlier would be April 26th, 1986 at 1:22 AM. That timing is correct to set us up just before the explosion.

We’re in Pripyat, Ukrainian SSR.

A woman named Lyudmilla Ignatenko, who is played by Jessie Buckley, happens to be awake to use the restroom. Afterward, she goes to the kitchen to get a drink. She doesn’t even notice the bright light in the distance out the window of her apartment. Then, a moment after we see the blast, the sound hits, shaking the apartment.

That, she noticed. So did her husband, Vasily, who wakes up. Together, they look out the window at the glow in the distance. The explosion throws a pillar of blue light into the sky that looks like something we’d expect to see in a science fiction movie.

Before we go any further, I wanted to touch on how the explosion looked. What we see in the series is most likely pretty accurate, but I also think we should set some expectations. It’s not like it was caught on film, so no one really knows what it looked like for absolute certainty.

Remember, this was in 1986. There weren’t cell phones with cameras in everyone’s pocket. There weren’t security cameras in houses, businesses or even cars like we see today.

It was also 1:23 in the morning. And Chernobyl was specifically built to be away from the huge city it provided power to: Kiev. Of course, that’s now the city of Kyiv since Ukrainian independence following the collapse of the Soviet Union in 1991.

The city of Pripyat mentioned in the series is a real city. It’s located about 62 miles, or 100 kilometers, away from Kyiv and was built in 1970 primarily as a home for people working in and around the Chernobyl power plant. By 1986, there were about 49,000 people who lived in Pripyat. For comparison, the city of Chernobyl itself where the power plant was had about 14,000 residents in 1986.

So, that’s another limitation of the eyewitnesses to the explosion. Not only was it in the middle of the night in the year 1986 where automated monitoring technology just wasn’t as common as it is today…but it’s not like there were millions of people around.

With all that said, it’s not like there was no one around either.

There were people who worked at the plant 24/7, many of whom were alerted by the explosion itself and rushed to see what happened.

To see the explosion itself, there were some people who just happened to be fishing nearby at that moment. And by nearby, I mean very nearby. You see, there was a pond near the power plant that held water used to cool the plant. That pond was also used to stock fish—something they used as a way of showing how safe everything was.

So, there were a couple of guys who happened to be fishing in that pond about 800 or 900 feet away—about 250 meters or so—away from reactor number four when it exploded.

According to these eyewitness accounts, there was a fireball that rose from Reactor #4—or, as they referred to it, Unit 4. Along with the fireball rose a mushroom cloud of smoke. A red column of light from the explosion turned blue as it rose into the sky, surrounded by the black cloud of smoke.

It’s probably not what you want to see coming from a nuclear reactor. But, of course, that’s also looking at things through a historical lens where we already have an idea of what happened at Chernobyl.

At the time, they had no idea just how bad it was.

Yes, there was an explosion—two of them actually, one right after the other.

Yes, there was a fire.

The fishermen kept on fishing, though. There was no way they could’ve known how serious things actually were.

Going back to the series, inside the control room right after the explosion we can see the man in charge is Anatoly Dyatlov. He’s played by Paul Ritter in the series.

“What just happened?” Dyatlov asks the others in the control room as dust falls from the ceiling as a result of the blast. No one seems to know the answer.

Then, someone named Perevozschenko bursts in the room exclaiming there’s a fire in the turbine hall.

After a moment’s pause, Dyatlov figures it out…the turbine hall. That’s the control system tank. Hydrogen. That would cause the explosion. He turns to two of the men working the controls, Akimov and Toptunov, and berates them. He blames them for blowing up the tank.

That is all a pretty good dramatization of what most likely happened in the control room that night.

The reason I say it’s “most likely” what happened is simply because we have to rely on the memories of people who were there that night to piece together the story. That’s not unique to our story today—there are lots of times in history where we can only rely on the memory of those who were there. But it’s important to know that because memory can often be an unreliable interpretation of what happened, especially when it comes down to specific things we see in the HBO series like who said what.

With that said, the men we see in the control room in the series were real people. Anatoly Dyatlov was the deputy chief engineer. Aleksandr Akimov was the chief of the unit’s shift and Leonid Toptunov was the reactor operator. And it is true that one of the mechanics came into the control room to let them know the turbine hall was on fire.

Not to skip too far ahead of where we are in the timeline of the first episode, but a little later in the first episode there is some dialogue where Dyatlov, Akimov and Toptunov are talking about the tank. Dyatlov mentions the tank on 71 is 100 cubic meters. Akimov corrects him, saying it’s 110 cubic meters.

While it’d make sense for people who work at the Chernobyl power plant to understand what all that means, for those of us who didn’t, what they’re talking about is the location of the control system tank.

It was 71 meters, or about 233 feet, directly above the control room. It also held 110,000 liters, or about 29,000 gallons, of hot water and steam. As a quick little side note, that doesn’t mean the series is wrong to mention hydrogen. Hydrogen can be created by the reaction between steam and the fuel used in a reactor, and since hydrogen is extremely combustible it’d make sense to assume the hydrogen was the cause of the explosion.

But, the location of the tank is important because something we don’t see mentioned in the series is that Dyatlov expected all that hot water start leaking through the roof of the control room they were in at any moment.

One of the orders we don’t see him giving in the series that he actually did give was for everyone to move to an emergency control room. But, the series probably just simplified this, because it is true they never moved. Everyone was too focused on the alarms and indicators in the control room giving readings they couldn’t make sense of to pay attention to Dyatlov’s order to relocate. And, since the ceiling hadn’t started leaking yet, he didn’t push the matter. After all, every second mattered, and he knew they had to keep the reactor cooled.

This is important to keep in mind, though, because the more time that passed without the water leaking through the control room ceiling the more that became an indicator to Dyatlov that the explosion was probably not the control system tank.

If we go back into the series, though, Paul Ritter’s version of Anatoly Dyatlov has just come to the conclusion that it must be the control system tank that exploded. He orders water be pumped through the core. All that matters now is to keep the core cool, so the fire doesn’t affect it.

The man who burst into the room stops Dyatlov and says, “There is no core! It’s exploded!”

Anatoly Dyatlov pauses for a moment at this, thinking it through…then he disregards it. He’s in shock. The man persists, saying he saw the lid is off! But Dyatlov won’t believe him. RBMK reactor cores don’t explode, Dyatlov replies. You’re confused.

This whole concept of refusing to believe an RBMK reactor could explode was true…but it wasn’t because of a lack of education. If anything, it was quite the opposite: Their training was one of the main reasons they couldn’t even fathom the reactor core was what had exploded.

It was one of those things where the eyes saw something so unbelievable that the mind couldn’t comprehend the reality of it. There were simply too many fail-safes. Too many safety systems in place for that to happen. It wasn’t possible.

Even some of the plant workers who saw the aftermath of the blast would later recall their minds didn’t want to believe what their eyes saw.

To put it another way, they were simply blinded by their belief that the reactor was so safe it could never explode. Whatever had happened must have been something else—it couldn’t be the reactor. At least, that was the mindset for most people at the Chernobyl power plant that night. Of course, they would find out just how wrong they were.

Going back into the series, we see Anatoly Dyatlov ordering the men in the control room to pump more water into the core to keep it cool. We talked about that briefly a little bit earlier.

Now, if you’re like me and not a nuclear engineer, right about this point in the story it’s very helpful to understand how nuclear reactors work. So, remember where we were in the series with Dyatlov wanting to pump water into the core because it will make sense on the other side of this explanation of how nuclear reactors work.

In a single sentence: Nuclear reactors heat up water until it becomes steam which spins a turbine to generate electricity.

Of course, that is an extremely simplified version.

There are different kinds of nuclear reactors, but the one we hear about in the series is an RBMK reactor. And it is true that the Chernobyl reactor was an RBMK reactor. RBMK stands for a High-Power Channel-Type Reactor. Obviously, that’s the English translation. The letters RBMK line up better with the actual Russian words, reaktor bolshoy moshchnosti kanalnyy.

But, as you can tell from my butchered pronunciation, I can’t speak Russian! So, we’ll stick with calling it a High-Power Channel-Type Reactor, or just stick to RBMK haha!

There are a few things about RBMK reactors that’s helpful to keep in mind as we continue to learn about what happened at Chernobyl.

One of those things is they’re unique to the Soviet Union, and now Russia since there are still RBMK reactors around today even though the Soviet Union is not. That means in 1986, no other country had engineers with experience with RBMK reactors or any other training for them outside the Soviet Union. And as we’ve learned so far—inside the Soviet Union, the training for RBMK reactors only ever implied they had so many fail-safes and safety systems that the idea of an RBMK reactor exploding was unfathomable.

Another thing to keep in mind about RBMK reactors was that…well, Chernobyl wasn’t originally supposed to be an RBMK reactor. It was supposed to be what’s known as VVER. The English translation for that is Water-Water Energy Reactors. That was the Soviet version of the same type of nuclear reactor that’s in the United States, which is called Pressurized Water Reactors or PWR.

However, they decided to build RBMK reactors in Chernobyl instead because RBMK reactors could output twice the amount of energy as a VVER reactor and RBMK reactors could be built by machine plants that didn’t have any sort of nuclear industry-specific high-precision equipment.

So, basically, RBMK reactors were cheaper and more powerful.

That’s a win-win…right? Well, if that were true then we probably wouldn’t be telling the story today.

The last key thing to keep in mind about an RBMK nuclear reactor that I wanted to mention at this point in the story is that RBMK reactors use a graphite moderator in the control rods. No other reactor types do that, and we see graphite mentioned quite a bit in the HBO miniseries.

What does that mean, exactly? To understand that we’ll have to dive back into how nuclear reactors work for a moment.

So, earlier, we learned a nuclear reactor heats water to the point of becoming steam to then generate electricity.

The part that we’re talking about here is how an RBMK reactor heats the water. It does that through something called a fission reaction. That’s what happens a neutron hits a larger atom, splitting into two smaller atoms. Energy is released as well as additional neutrons, which can then repeat the process. That’s the chain reaction.

To help ensure the chain reaction continues more, something called a moderator is added to slow down the neutrons. That way you’ll get a better chain reaction and, in the process, more energy released. That results in more heat which results in more steam which results in more electricity.

The fuel used for a nuclear reactor is uranium. The uranium is made into pellets that are stacked into a metal tube called a fuel rod. In an RBMK reactor, it’s uranium-238 that’s slightly enriched with uranium-235.

The fuel rods with enriched uranium are positioned vertically inside the core of the reactor.

The core of an RBMK reactor is graphite—the same thing used in pencils, although for a nuclear reactor we’re obviously talking about something much bigger. The graphite core is more like the size of a house, and the graphite is a lot more pure than what’s in a pencil.

In the core, there are 1,660 vertical holes. That’s where the fuel rods are inserted.

But, it’s not like there are 1,660 fuel rods inserted.

You don’t want the chain reaction to go on and on unchecked forever, so there are also what are called control rods. The control rods are made of a material called boron carbide and, in RBMK reactors, there are graphite tips on the control rods. That graphite tip will play a part in the story later, but the boron carbide is a material absorbs the neutrons which, in turn, slows the fission reaction down.

With all that explained, the basic process then is that cool water is pumped into the core. It cools the core down, but it also flows around the fuel rods where the fission reaction heats up the water. Since heat rises, the steam comes out the top of the reactor where the reactor design forces the steam to the turbine where the electricity is generated.

More cool water is pumped in, it cools the core, is heated and leaves as steam.

If things get too hot from the chain reaction generating too much heat than the water coolant can handle, then you insert more control rods to absorb the neutrons and slow down the chain reaction.

And so on and so on, the balance continues as electricity is generated.

Okay, so in a nutshell, that is how RBMK nuclear reactors work. And yes, all that is still an extremely simplified version.

But that will help us understand the rest of the miniseries a lot better because…well, it’s a lot easier to understand how things went wrong when we know what they were supposed to be doing in the first place!

So, remember where we were in the miniseries?

Anatoly Dyatlov gave the order to pump water into the core just before he left to go to the Administration Building to talk to Viktor Bryukhanov and Nikolai Fomin. He really did do that, but it wasn’t the only order he gave. That was just one of the orders Dyatlov made after the explosion that would end up making an already terrible situation even worse.

The order to pump water into the core was his primary focus though.

A big part of that has to do with what we talked about earlier—the disbelief that the core itself had exploded. But the indicators in the control room were also telling them that there wasn’t any water at all flowing into the core. If the fuel rods didn’t have any coolant, they’d melt. That would be bad.

So, he thought the huge graphite core was still there and since they’d pushed the AZ-5 button—we’ll hear more about that later in the series—but basically that button inserts all the control rods into the core at once to completely halt the fission reaction. Since they did that, Dyatlov believed that all he had to do to cool the reactor down was to keep pumping cool water in. Since the chain reaction had been stopped with the control rods, the cool water wouldn’t be heated anymore and any residual heat that was there would eventually cool off with more cool water added.

At least—that was the idea behind his order to keep pumping the water into the core.

He also believed the fission reaction had been shut down. But because the indicators were showing no water was being pumped into the core, that’s why Dyatlov’s order was to try and restart the emergency water pumps. Those had been shut off for the test, but now he ordered them to restart those pumps in an attempt to cool the reactor before the fuel rods melted.

Or, basically, get water into the core as fast as you can. That will save the reactor and the fire brigade can handle the fire before things get worse.

That was the plan, at first.

Something we don’t really see in the series, though, is that plan was more complex than it sounds because Dyatlov realized pretty quickly that the fission reaction had not been shut down like he thought at first. From the control room indicators, they could tell the control rods hadn’t descended all the way like they were supposed to when they shut down the reactor. Not only that, but the control rods had stopped about one-third of the way down.

That’s additionally bad because, as we learned earlier, the control rods in RBMK reactors have graphite tips. So, not only was the boron not slowing down the fission reaction, the partially-inserted control rods with graphite tips were basically acting just like the graphite core around it—increasing the fission reaction!

Thinking fast, Dyatlov thought if the button to insert the control rods all the way didn’t work, maybe they could be fully inserted manually. So, he ordered a couple of interns who had been in the control room to learn from the test to go try that. But then he immediately realized that was a bad idea because the control rods were huge—they can’t be inserted through manpower alone. Even the manual controls required a servo motor that was powered by electricity. Since there wasn’t power, the servo motor wouldn’t be able to help move the control rods so there’d be no way they could be lowered manually.

But, the two men had already left the control room. Dyatlov ran after them for a moment, but they were down the hall and out of sight.

They couldn’t have known it at the time, but they were trying to do an impossible task and running even closer toward the exploded core.

While he was in the hall outside the control room, Dyatlov noticed it was filled with dust and smoke from the fire in the turbine hall. That was a fire he already knew about, and one that we talked about briefly before when we found out about his decision to call the fire brigade to deal with the fires.

If we go back into the series now, there’s text on the screen to tell us it’s 2:30 AM.

There are two things we see happening that we’ll talk about. The first is what I just mentioned, the fire brigade coming—we’ll come back to that in a bit.

The other is when we see Viktor Bryukhanov getting the phone call that wakes him up about the accident. He meets Nikolai Fomin at the Administration Building where they both go into what looks like a bunker with a long conference table in it. Dyatlov is already there and he starts filling them in on what happened.

The basic concept of this is true, although it was around 2:00 AM when Bryukhanov got the call to wake him up about the accident. That’s kind of splitting hairs, though. What’s not splitting hairs is something we see Con O’Neill’s version of Viktor Bryukhanov tell Dyatlov that there’s no way they can blame him for the accident—he was asleep when it happened!

This whole conversation we see between Dyatlov, Bryukhanov and Fomin in the series is a simplified version of what happened. In truth, they talked on the phone first…they didn’t talk in person for a few hours after we see it happening in the series.

Something else we don’t see in the series is that even though Bryukhanov didn’t know the extent of the explosion he had gotten the call about, as the bus he was riding to the plant got closer, he noticed the top of Unit 4 was gone.

At that moment, he knew he would be blamed for it. He was in charge of the power plant, so it didn’t matter that he was asleep when things went wrong. It was a big enough of a deal that he’d take the fall for it. Anything that goes wrong, you’re the one in charge so you’re the one who takes the blame. That’s how things worked in the Soviet Union.

Talking to Anatoly Dyatlov also wasn’t the first thing Bryukhanov did when he arrived at the plant. He actually decided to investigate himself and went toward Unit 4. But, he stopped when he saw pieces of graphite on the ground and the building next to the reactor hall in complete ruins. He didn’t want to see more, so he went back to his office to make phone calls.

It was to the chief of the night shift, a man who isn’t in the series at all. His name was Boris Rogozhkin. He was the one who had gone to the control room to talk to Dyatlov, Akimov and Toptunov. So it was Rogozhkin who told Byrukhanov over the phone what Dyatlov had said: We pressed the AZ-5 button, and 12 to 15 seconds later there was an explosion.

The AZ-5 button is the emergency shutdown that lowers all the control rods into the core, stopping the fission reaction. It definitely was not supposed to cause an explosion!

Once Bryukhanov got off the phone with Rogozhkin, he turned around and started calling his superiors to let them know about the accident—at least, what they knew so far. After that, Bryukhanov called Dyatlov to tell him to come over to the underground bunker to talk to him directly. But that wasn’t until around 4:00 AM, not soon after 2:00 AM like we see in the series.

Speaking of which, if we go back into the series, we see the firefighters continuing to battle the flames.  According to the series, they first arrived on scene around 1:30 AM.

We see shots of them here and there between things we’ve seen in the reactor. Time passes until around 3:30 AM, and there’s some dialogue between the firefighters that lets us know they’ve done everything they can from the outside. They need to start making their way to the roof now. We also see some of the firefighters reacting to some of the debris—debris that’s molten hot in some cases, other debris that’s not hot to the touch but still causes burns after the firefighters pick it up.

The series has so many different angles to tell the story that we don’t see everything from every angle—and that makes sense.

But in the true story, by the time 2:00 AM rolled around, firefighters were starting to address the fire on the roof of Unit 3—it was connected to Unit 4. They quickly realized it was more than just fire. Less than half an hour later, the firefighters were starting to get sick. They didn’t know exactly what the cause was—but they knew enough about fighting fires to know there was something different this time.

Still, there was a fire to be extinguished.

We don’t see this character in the HBO miniseries, but the commander of the fire department that responded was the 35-year-old Major Leonid Teliantnikov.

By the time 2:30 rolled around, the fire on the roof of the reactor hall had mostly been extinguished, but Teliantnikov noticed his men weren’t right. They were sick. So, he ordered them to go in an ambulance to the Pripyat hospital. An hour or so later, around 3:30 AM, Teliantnikov and his men were battling the flames on the roof of Unit #3. Except, he’d been exposed too much himself. So, he went to the hospital himself, leaving the firefighters without their commander.

This is way beyond the scope of episode number one, but it was closer to 7:00 AM when the firefighters finally had the flames extinguished.

And since I mentioned episode number one, if we head back to the HBO miniseries we’re at the end of the first episode where a phone rings.

Tying into the beginning of the episode, Valery Legasov is the man who answers the phone. On the other end of the line is Boris Shcherbina. Through the conversation, Legasov finds out about the accident and that he’s been assigned to a committee to manage the accident.

Specifics of the conversation were surely made up for the series, but the basic concept here is true.

Boris Shcherbina was a real person. He really was in charge of the commission to get to the bottom of things…and to offer another bonus point to the accuracy of things, the creators of the series even found an excellent actor of the same age. The real Boris Shcherbina was 66 years old in 1986 when he was put in charge of the commission, while the actor playing Boris Shcherbina in the HBO miniseries, Stellan Skarsgård, was 68 years old in 2019 when the series was released…and probably a year or two younger when they filmed the series before being released.

So, that’s a minor thing, but something I think is worth pointing out to highlight the level of detail the creators went to in this series.­

Both Valery Legasov and Boris Shcherbina were very real people involved in the true story…

…and those are two names we’ll hear about a lot more in our upcoming episodes as we dig into the rest of HBO’s Chernobyl miniseries!



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