The producer actually discusses that point in the companion podcast.  They considered it, but eventually found it distracting because Russian accents can quickly become comical a la Boris and Natasha.  So instead they decided to let the actors use their normal accents.

For those interested, here's the podcast.  The producer goes into what they changed and why in the story, vs what they tried to get right.  I found it interesting.

The Luxor-like beam is a bit overdone, but witnesses did report a substantial glow above the reactor.

https://www.theguardian.com/world/2006/mar/26/nuclear.russia
Listening to the podcast reminded me of an interesting factoid... the glow wasn't from Cherenkov radiation, but rather that the radiation intensity was so high that there was a glow from ionized air. Essentially they had a miniature artificial aurora.

Can you explain void coefficients?  I want to sound smart around the water cooler tomorrow.

https://en.wikipedia.org/wiki/Void_coefficient
The meaning of the term "void coefficient" is in relation to the proportion of steam bubbles vs liquid water... more heat makes more steam leading to what result.

Negative void coefficient means that as reaction power increases, extra heat leading to more steam bubbles slow the reaction - self-regulating in a way.

Positive void coefficient means that as reaction power increases, extra steam bubbles further increases reactivity, leading to instability and runaway behavior if accidentally put into the wrong state.  The RBMK reactors had an automated safety system to try to counteract those tendencies but those systems were disabled for the experiment they were trying to run.

The RBMK reactors also had a bizzare design feature - they put moderator rods on the bottom of the control rods. The effect of that is that as control rods were inserted into the reactor, that they would INCREASE reactivity for a time before the reduction in reactivity would come into play. There was also supposedly some kind of unexpected behavior of Xenon poisoning. This reactor design was just never intended to operate at that low of a power level and was not safe or stable.

Yep, in western reactor design the water is two things...a coolant to transfer the heat to the turbine to make electricity and the neutron moderator. The moderator slows the neutrons down enough that they have a higher probability of actually hitting a uranium atom and causing a fission.

The nifty thing is that low enriched fuel (less than 10% ish)in western designs won't react in a commercial power reactor without a moderator. So.. if it all goes sideways and the coolant leaks out...the reactor shuts off.  Also, changes to the water like lower density or steam bubbles make it a less effective moderator. So as heat goes up the reactor has a tendency to want to slow down. It's a natural built in safety. Yea physics!

Graphite moderated reactors don't run bathed in water, they have cooling channels with water in them but it's basically a huge graphite block with holes in it.  As voids or areas of lower density occur in RBMK reactors they have the opposite effect, they tend to cause more fissions..or an increase in reactivity.  The hotter they get..the hotter they try to get.

Xenon is a natural by product of uranium fission, happens in all reactors.  The problem with xenon is that it is the most powerful neutron absorbing element known to man.  Reactors are meant to run..but just barely..so we can control them.  They make just enough neutrons bouncing around to accelerate the reaction and not run away completely.  Then we ever so slightly change the balnce by moving control rods in and out, they are the throttle for the reactor. Control rods are made of neutron absorbing materials..like boron.  Xenon screws that whole balance up.

Due to the request of the power grid controller in Kiev the trip test was delayed and Chernobyl ran at a low power setting for a long time. This allowed xenon to build up.  Suddenly the control rod setting that held the reactor at 60% wouldn't hold it there anymore, the xenon was slowing things down. So they pulled out more control rods to keep it running. And more and more as xenon built up. Eventually they had to pull out rods that should never be moved, the rules said they should never be moved...but they wanted to keep the reactor running so they could run the turbine trip test. So they pulled them.

The reactor got hotspots, but its huge so the operators couldn't see on the instruments that it had hotspots.  As it started to accelerate, it started using up all that xenon, as the xenon went away it started accelerating faster and faster. The hotspots were so hot that they started creating voids which made it accelerate even faster and making more heat and using up more xenon...so it was a feedback loop. Every bad thing made other bad things happen even faster.  Heat started damaging the channels in the graphite. By then the operators knew something was wrong so they SCRAMed the reactor.  That should have inserted all the control rods and shut it down...but..the rods were graphite tipped...to keep them from jamming I think. So when they entered the graphite entered first and graphite is the moderator...so it made the situation worse before it made it better. Also there is a theory that the control channels were already distorted by the hotspots and the rods physically couldn't insert all the way.

Only a few seconds after the rods entered Chernobyl hit 100x its rated thermal power and exploded.

It's a chain of events that had to be just so in order to make a disaster.

This is my take...

The RBMK reactor was designed for non-enriched (natural) uranium, so had a large fuel volume. Water cooling through the fuel tubes with graphite moderation. Sound familiar? Yes, just like the US plutonium production reactors at Hanford, and the Soviet's initial plutonium production reactor which was based on stolen design of the US reactors. The Soviets were using the RBMK power reactors as distributed plutonium production. But the reactor design was not suitable for the operating demands of power production as the operating envelope just wasn't flexible enough.

Oh yeah that's a pretty commonly accepted thought.  The RBMK could be fuel cycled easier...maybe even while running?....not sure on that one... so it could be used for a breeder.  They said they used that design for cost reasons...maybe...but they at least liked the idea that it was a possible plutonium producer.   Objectively speaking, it's not up to par with western designs but run according to the operating procedures they are safe.    They are still running, 30 years later.

My take on it is that they shut off all the safeties and flew it into a mountain...metaphorically speaking.   They didn't melt it down...they blew it the fuck up.   It's tough to call it an accident, everything they did, they chose to do despite it being against the operating rules.   Negligence?  At least.   I've seen it called "a lack of safety culture"...I was a safety engineer...lack of safety culture doesn't cover it.   It was criminal negligence bordering on a crime against humanity.

Western reactors don't have the dangerous characteristics of the RBMK so I'm not sure you could blow up a Westinghouse BWR the same way...but put the backup gensets in the basement in a earthquake and tsunami zone and watch what happens.  They survived the one of the largest earthquakes and tsunamis in history only to melt down because the power went out and couldn't be restored fast enough.

Next weeks episode with have the "Bio-Robots" who wore home made lead armor and shoveled radioactive debris.

I'm no tinfoil hat conspiracy theorist but I have never believed the reported death toll of 28 directly and 15 indirectly.

Question regarding the Soviet System.

If the engineer who was ordered to climb the building and look down into the reactor had refused, what would have happened?

Would he have been shot on site?  We see they sent an armed soldier with him, if he didn't climb would it have been a bullet in the back of the head?

Or, would they have arrested him and held a make believe trial and then execute him?

How about on a normal day without any disaster.  If someone working there at the power plant decided they didn't like the work, could they just simply quit and look for another job?

I know there were no individual rights or liberties, but how much flexibility was there in deciding your own career path?

let me put it to you like this:  try and find someone to ask that refused.

I was reading one account where the military was ordered to shoot all the family pets that were left behind after the evacuations. Most were sick and dying and they found a lot of them by their whimpering/howling.

That's the kind of minor stuff that drives home the horror of such a incident.

The soldier doesn't shoot the engineer, he just reports back.

Then the engineer and his wife get sent to the gulag. Using them as slave labor is more efficient than just shooting them. Punishing the whole family is more incentive for people to obey in the first place.

Not sure if this has been posted yet, but someone compiled a very large album of pictures and diagrams, and did a write up. Very cool.

https://imgur.com/a/TwY6q

I watched Episode 1 today after I got off work. I liked it, looking forward to next week (and to finally have something interesting to watch on a Monday.)

In a lot of the "secret cities" living conditions and the ability to purchase better food and even western goods was a lot better. In other words the worker and his/her family lived better.

Sort of the Soviet version of a police "dental plan".....They would have to think long and hard to give that up by disobeying orders.

While Pripyat was not a "closed city" as far as I know standard living conditions were "better" than where they would end-up.

Pripyat was supposedly a pretty awesome city by 80s Soviet standards. Stuff was new, everybody was young the city was nice, nice parks, theaters.

It was certainly a "company" town, everybody worked at the plant. As was pointed out in the first episode it was V.I. Lenin power station so pripyat probably got a high priority from the system.

Agreed, I question the death toll as well.  It was the USSR, of course they buried some of the damage.

Great album.

The actors & styling of them in the show bear a remarkable resemblance to the real-life people they portray. Take a look at this photo:  https://i.imgur.com/DRjOxG5.jpg and you will have no trouble identifying them as portrayed in the show.

Judging by the trailers I think that will be shown.

watching 3 mile island documentary on youtube, that indecent was very close to a complete meltdown, explosion. Sure the reactors are better designed but fuckups  can and do happen. Its truly unbelievable that there was no way for them to tell how much coolant was in the reactor and only one phone line into the control room. Its astounding.

all of this

Just watched the first episode, it was enjoyable.

I wonder if we will ever find out the real death and serious injury toll?

I doubt it.

I would think the cancer rates, of the people in town and their children born well after 1987 is very high.

The imgur album has images of the refueling system, which is done one rod at a time while in operation. No spent fuel storage of any substance. Shudder to think of how they were handling and transporting spent fuel for reprocessing.

The liberal media is saying there are "chilling" similarities between the war on the truth of the USSR and the Trump administration.

I read the headline and killed myself due to disbelief, this is a post from beyond the grave.

I liked it a lot.

Unfortunately, as a proponent of Nuclear Power, I doubt this miniseries is going to help gin up a desire for more nuclear plants in the US.

My take after watching:

- radiation is still terrifying as all fuck
- I feel for the firefighters and folks who were in scene. Looking straight into the fucking core? Holy shit.
- the Old Soviet dude talking about the State reminded me of Bernie Sanders
- surprised it painted communism and the “State” in such a rightfully poor light. HBO and all that.....seems like some red pills were taken

And finally....government aka The State will always fuck you over. Why do people here want that type of commie governess? Fucking maddening.

Edit: also, there’s some smart fuckers in this thread.

30,000 R/hr is about as horrible as it gets. Apparently the radiation level was estimated to be that high in places.

It's just Soviet culture. Do what you're told. Someone in the bureaucracy says to run a test, you run the test. The system is superior and has everyones best interest at heart, so the mantra goes, except that the whole system is a game of telephone. There's a line in the show to the effect that a Soviet reactor isn't capable of being a catastrophe, so a catastrophe hadn't happened. If a catastrophe happened, it must have been an enemy attack or sabotage.

The only meter available to the peons only reads to 3.7 R/hr. There is a meter that will read higher, but it's locked in a safe and only available upon permission of a political official.

Not that there’s any arguments going on here but I’ve heard GD described as “some of the smartest people in the world arguing with some of the dumbest mother fuckers on the internet.”

Bernie was visiting the Soviet Union a couple of years after Chernobyl. I'm sure he fit right in.

Current energy economics and cost/schedule overruns on the few existing US and EU new-builds are more than sufficient to squash the idea of nuclear expansion.  No hysteria needed.

I see this series in a very different light.  I see it as a good reminder of what one's signature means.

When they told the guy to go to the roof with the guard in tow watching him and he turns around with his face turning colors

And the guy who opened the door and walked in overlooking the reactor

Looking right at the devil.

The upper third of the fuel assemblies completely collapsed in a combination of cladding failure and ceramic fuel melt.  Not sure how much more melty you are looking for, but that's certainly a meltdown in my book.  And there was a hydrogen explosion inside the containment building - plastic stuff inside of containment, such as phones and the like, showed signs of scorching/melting.

I think there were 2 phone lines going into the control room, but that's based on past conversations I've had with colleagues who were either on one of those lines, or sitting next to someone who was.  Also good to keep in mind that it's my recollection, on top of their recollection., and memory being what it is, well...

link?

The old guy had all the hallmarks of being a political commissar.

The other takeaway is that there will always be those who will seek to find someone to take the blame during the crisis rather than working the problem because they are in total denial as to the seriousness of the problem.  

Do you think there is any truth to the notion that a contributing factor to the TMI accident was the fact that many of the operators and engineers were former Navy nukes and they had a bias toward not letting the pressurizer go "solid".  I've read this theory in someones book or paper on the subject.   I understand why the navy would have issue with that given the applications.

The father of a friend growing up was a retired navy nuke engineer and was living in Hershey Pa at the time and was actually called to TMI in the hours after the emergency was declared. He was legitimately the smartest person I have ever met.  Scary smart. Worked for westinghouse at one point...designing..stuff.. I wish he was still around now that I am older and wiser.....and full of questions.

You wouldn't think that level  of idiocy could be attainable but yet, here it is

Watched it last night.

That site was blasting high intensity radiation into the atmosphere as soon as it blew and they denied it to themselves, as well as everyone else until it was too late.

The series does a good job of showing the fear of decision-making or problem-solving woven into the Soviet mindset, as well as the layers of bureaucracy that hamper any kind of progress, while insulating itself from consequences and fixing blame to whatever hapless person was within proximity to do so, especially if they were viewed as having suspicious allegiance to the party.

Keep in mind the Ukraine and Russia have never recovered from this culture, but have had parts of it supplanted with kleptocracy.

Going to watch.

A. N. N. O. U. N. C. E. D. 2 https://t.co/ouCo9Q5unn pic.twitter.com/vZef7kTfvy

— S.T.A.L.K.E.R. Official (@stalker_thegame) March 28, 2019

I'm just reading up on it on World Nuclear Association's site right now, covering the sequence of events.

Sequence of events video with graphical explanation showing basic representation of the reactor power output, the test, and what went wrong.

Watch this before watching the HBO series, especially from 9:00 forward if you want a sequential explanation of what went wrong with their test and the steam-driven positive power coefficient:

Hi if this hasn’t been covered already that last paragraph is false.

Three men waded knee deep into the water to find the valves. Most of the after had been pumped out by fire engines.

All three lived for a long time. Two are still alive. One had a heart attack around 2004 .

I don’t know if it prevented anything as I don’t know if the molten fuel got into that room.

They were still brave and still received radion. But the story in not true.

Those two guys sloshing through the water to turn those valves...............and all those people watching from afar with radioactive dust falling on them

Has the dome covering for the plant ever been completed and sealed?

So was this a bad thing?

Yes, my boy & I watch a documentary every night and that was one he picked out last month.  The new enclosure was completed and rolled into place.

FWIW, $5/month donation gets you access to all of the PBS documentary archives streaming (NOVA/Frontline/Nature series etc).  There are some really good ones in there, particularly from before they got all political.

ETA:  Here is the documentary

Building Chernobyl's Megatomb

The operator issues are broader than how they handled the pressurizer.  My first inclination is to call it an institutional problem, but institutional is the wrong word, because it really was a problem mostly confined to the TMI-2 operators.  A few years ago, I had a lengthy discussion with an engineer who trained the TMI-2 start up team - an in house discussion, relating to some other B&W 177 or 205 stuff, so it wasn't some off the cuff remarks, but instead, conversation relating directly to the operating procedures of B&W 177 plants.

But, context is important, and just like most accidents, there's no singular cause.  And look, unless you are really thinking carefully about the steam tables, it would have been easy to look at the conditions in the pressurizer, and think you know the statepoint, when in fact, it was at a different part of the curve.  Everything looks so clear after the fact, when you can look at everything as a function of time in one encompassing snapshot, but dealing with this stuff in the moment, at just one of those timestamps, it's quite different - whether it's nuclear, aerospace, whatever, my experience is that it is very difficult to project out into the future from real time statepoints.

Regardless of how the got into the accident conditions, though, some of their response decisions were inexcusable, even in context.

My girlfriend and I watched the show Monday night when it came on, I didn’t think she would enjoy it. We watched it for the third time tonight

I’m still trying to wrap my head around the entire thing but that video helped a lot, I suggest everyone that isn’t a nuclear physicist watch it.