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  • MICHAEL SHORT: We've actually got a special guest today.

  • It's Jake Hecla, one of the seniors at NSE

  • who's gone on to Chernobyl for the second time, just returned

  • from there two weeks ago.

  • So if you remember on Tuesday, we

  • went through all of the physics and intuition

  • about why Chernobyl happened.

  • And we left off on what does it look like today.

  • So Jake is going to tell you what does it look like today.

  • JAKE HECLA: All right, so first off I'm

  • actually going to go over a bit of the reactor physics involved

  • with the Chernobyl accident.

  • I realize you guys have already covered this to some extent.

  • But I didn't plan for that.

  • So it's in my presentation.

  • MICHAEL SHORT: It'll be a good review.

  • JAKE HECLA: Yes, also I am a little sick.

  • So I'm probably going to start coughing, apologies.

  • I'm not dying.

  • It's just a cold.

  • AUDIENCE: Radiation poisoning.

  • JAKE HECLA: I have heard that joke about eight times

  • in the last two days.

  • And I'm so done with it.

  • But yes, it's not radiation poisoning.

  • AUDIENCE: [INAUDIBLE].

  • JAKE HECLA: Yeah, all right, where is Chernobyl?

  • Ah, dang it.

  • Come on, no, go the other way, the other way, yep.

  • OK, there.

  • OK, so one of the first questions

  • I got when I said I'm going to go and visit Chernobyl is wait,

  • isn't that a war zone?

  • Not quite.

  • So the Ukrainian, the war in Ukraine

  • is mostly in this portion over here.

  • It's not entirely under Rebel control in that area.

  • And I say "rebel" in quotation marks

  • because rebel means Russian.

  • However, if you notice those arrows,

  • Russian forces are built up all along that border.

  • So while it's not an active war zone,

  • it's certainly not a place to be spending

  • a large amount of time.

  • That said, Chernobyl is north of Kiev by about,

  • I don't know, let's see, 200, 250 kilometers.

  • So it's not completely out in the sticks, right.

  • Hopefully this gives you good sense of roughly where it is.

  • All right, so what is the Chernobyl nuclear power plant

  • look like?

  • It consists of four finished reactors.

  • There are two unfinished reactors, unit 5 and 6, that

  • are not shown in this image.

  • Units 1 and 2 are located at the right.

  • Those were constructed in the 1970s and early 1980s.

  • All of these reactors or the RBMK type.

  • Units 1 and 2 operated with some success--

  • I'll go into that later--

  • for a number of years before the accident that happened in 1986.

  • We also had some call outs up here that

  • show the, some of the incidents that I'll

  • talk about here a little bit later in the presentation.

  • But this just gives you a general idea of the layout.

  • So it's two separate buildings for units 1 and 2.

  • And then units 3 and 4 are in one building, all connected

  • by this turbo generator hall.

  • So this is where the generators that

  • turn the steam from the RBMK into power, r.

  • This is one giant--

  • well, before the accident, this was one giant, not separated

  • hallway, basically.

  • So you could walk from one end to the other, theoretically.

  • All right, so what is an RBMK?

  • An RBMK is a light water-cooled, graphite-moderated,

  • channel-type reactor.

  • This means that it does not have a giant pressure vessel

  • like you would see in a VVER or an equivalent American

  • light water reactor.

  • Why does that mean anything?

  • Well, building giant pressure vessels is very difficult.

  • If any of you've done research on manufacturing

  • of nuclear reactors, you'll find out

  • that the equipment necessary to construct a reactor

  • pressure vessel is not actually something

  • we even have in the US anymore.

  • Is it Korea that does it for us now?

  • MICHAEL SHORT: Japan Steel Works.

  • JAKE HECLA: Japan that does it now.

  • In the Soviet times, it was very, very difficult

  • for the Soviet Union to produce such pressure vessels

  • at any kind of reasonable rate.

  • So the RBMK got around this by using

  • individual channels that were their own pressure vessel,

  • so to speak.

  • So the way this works is, let's just start on the cold side.

  • You take in cold water, goes here through these things.

  • These are main circulating pumps--

  • MCPs, as you'll see them referred

  • to later in the presentation--

  • goes up through the bottom up the core.

  • These are the hot fuel rods.

  • The water goes from liquid to steam phase as it's

  • flowing through the channels, comes out the top,

  • goes to the steam water separators.

  • Steam goes to the turbines, turns the turbines,

  • makes electricity.

  • The important thing to remember here

  • is that we've got a giant graphite core.

  • The graphite is what is doing the moderating

  • in this circumstance.

  • It is not the water.

  • This allows you to run very low-enriched uranium.

  • So you could theoretically run an RBMK

  • on I believe it was 1.2 percent was as low as they could go.

  • But regardless, extremely low-enriched uranium,

  • which is convenient if you don't want to waste a lot of time

  • enriching uranium.

  • The problem with this is that you have a giant core.

  • If you recall the scattering cross-section for graphite,

  • it's pretty small.

  • And the amount of energy lost per collision

  • is likewise also fairly small.

  • So the core on this thing is, let's see, 11, yeah,

  • 11.5 meters across.

  • The core for an equivalent American reactor--

  • so well, there is no real equivalent to this--

  • but for, let's say, an AP 1000 reactor

  • of equivalent electrical output, is about four meters across.

  • So the core is huge.

  • As I already discussed, this is what the individual pressure

  • channels look like.

  • So cool water comes in the bottom, goes by the fuel rods,

  • pops out the top.

  • The RBMK had some serious design flaws.

  • So as I said, the core is huge.

  • This allows local power anomalies

  • to form really, really easily.

  • If you look at the core, one portion

  • can be kind of neutronically separated from the others

  • because neutrons just don't make it all that far when

  • diffusing across the core.

  • So you can have very, very high power in one corner

  • and very low power in the other, which is not something that

  • can develop in a physically smaller core, which

  • has a characteristic scale equivalent to that

  • of the neutron being free path.

  • Further, the encore flux monitoring on the RBMK

  • is seriously deficient.

  • So there are a variety of neutron detectors

  • that exist around the periphery of the core.

  • But they're wholly insufficient to catch these local power

  • anomalies.

  • Chernobyl actually found out the hard way on this one.

  • In 1982, unit 1 suffered a quote "localized core melt,"

  • not really something that can happen in LWR, really

  • any other type of reactor.

  • But a couple of the fuel channels

  • actually experienced one of these local power

  • anomalies and ended up melting.

  • So if you go into the control room of unit 1,

  • you can see that on the fuel channel cartogram on the wall,

  • there are two of them that are just Sharpied out.

  • And those are the ones that melted.

  • Further, it has a positive void reactivity coefficient.

  • What does that mean?

  • Well, when the water boils in the core,

  • the density of the water there goes down.

  • And the power of the reactor ends up

  • going up because the water is primarily

  • acting not as moderator but as a neutron absorber.

  • This is bad for a whole variety of reasons.

  • And they found out quite catastrophically

  • in 1986 exactly why.

  • Further, the system is extremely unstable at low power.

  • So how did the 1986 accident happen?

  • It was part of this thing called a turbo generator rundown test.

  • The general idea is that if you have an off-site power failure,

  • and your main circulating pumps are no longer

  • have off-site power, you somehow need

  • to keep water flowing through the core, such

  • that the fuel does not melt.

  • The problem is that the backup, large diesel generators,

  • are just that.

  • They're large.

  • They're diesel.

  • And therefore they're very, very slow

  • to come online and come up to full power.

  • The way that you can bridge this gap

  • is by using the energy that you've stored in the turbines

  • to effectively power the main circulating pumps

  • until the diesel generators can come up online.

  • When unit 4 was fully constructed in 1983

  • and turned on for the first time,

  • they had never actually done this test

  • where they did a turbo generator rundown,

  • despite the fact that it was required by law in the Soviet

  • Union that all new power stations should

  • have this test performed.

  • It was delayed until 1986.

  • And yeah, it was delayed until 1986 is the long story short.

  • The test procedure-- sorry for all the text on this slide--

  • is basically as follows.

  • So you would ramp the reactor down.

  • So you would bring it from a normal thermal output

  • of up to 2,400 megawatts thermal,

  • down to 600 or 700 megawatts.

  • You'd bring the turbo generators up to full speed.

  • So you'd store as much energy in them

  • as you possibly could, then cut off the steam supply such

  • that now you are just extracting energy from the spinning turbo

  • generator.

  • This would then be used to power the main circulating

  • pumps, each of which took about 40 megawatts.

  • There are eight of them total.

  • I believe six could be used for normal operation.

  • The rundown would take somewhere in the range

  • of 60 to 70 seconds.

  • And hopefully by this time your diesel generators

  • would be turned on, pumping water,

  • and everything would be fine.

  • What happened in the test was decidedly quite different

  • from that.

  • So on April 26, 1986, they attempted

  • to begin this test about six hours behind schedule

  • because there was an incident in another part of Ukraine,

  • in which a coal power plant went offline.

  • So what happened was the authority

  • for the grid in the area ordered that Chernobyl

  • should stay online at full power for an additional six hours.

  • They began the test by bringing power down.

  • But as a result of running for an extra six hours,

  • they'd built up a significant amount of xenon precursors

  • in the core.

  • So when they started turning the power down,

  • the power started going down, and down, and down.

  • And they were unable to arrest its drop.

  • What ended up happening was that the power dropped all the way

  • down to 30 megawatts thermal.

  • And the reactor operators kind of panicked.

  • Their response to this, instead of canceling the test,

  • was to pull out as many control rods

  • as they could get their hands on.

  • They did so.

  • And this managed to rescue the thermal output of the reactor.

  • And it bumped up to around 200 megawatts thermal.

  • At this point, the reactor was in an extremely unstable state.

  • Mind you, almost all of the rods that they could get their hands

  • on were out of the reactor.

  • The only thing keeping reactivity

  • at a reasonable level was all the xenon

  • that was built up in the core.

  • At this point, they began the turbo generator run down test.

  • They shut off steam to the main turbine, or one of the turbines

  • after it was run up to full power,

  • and then attempted to run the main circulating pump.

  • The main circulating pump started drawing down the energy

  • from the spinning turbine.

  • And as a result, it ran slower and slower,

  • meaning that the flow through the core

  • was less and less, more water boiled, going into steam,

  • which increased the reactivity.

  • As a result, the power output of the court went up.

  • It burned out more xenon.

  • And the cycle continued.

  • They noticed a power excursion, about 40 seconds

  • after they began the test and at this point

  • recognize they were in bad territory

  • and hit the scram button.

  • This would jam pretty much all of the available control rods

  • into the core, including some emergency extras,

  • and shut everything down.

  • In most circumstances, this would be a fairly safe move.

  • But in the case of the RBMK it was most certainly not.

  • RBMK control rods have a graphite tip on them.

  • When jammed into the core, they caused a localized power

  • increase because the graphite is a great moderator.

  • And it is displacing water, which is a great absorber.

  • And as a result, after they made it a couple meters

  • into the core, the increased pressure

  • in the core from the power output, which

  • was localized around the tips the control rods,

  • ended up shattering the control rod drive mechanisms.

  • And instead of turning off, the cycle basically just continued,

  • power continued to ramp up over the next couple of seconds.

  • It eventually reached somewhere around 10 to 20

  • times the maximum rated thermal output of the system.

  • And a massive steam explosion ended up

  • ripping through the facility.

  • It tossed the 2000 ton biological shield

  • on top of the reactor through the roof of the facility.

  • It injected a significant portion of the fuel,

  • as well as the moderator in the core.

  • And it started a massive fire around the facility.

  • Just to give you a good sense of scale,

  • let's see, if I've got the virtual laser pointer.

  • That's a person right here, this little guy.

  • This is the top of the biological shield,

  • Elena shield.

  • And then this is a model, a cutaway model of the Chernobyl

  • reactor facility with the shield,

  • and with the flipped shield that went up through the roof

  • and came back down.

  • So as you can see, it was an utterly massive explosion.

  • So the damage to the reactor was immediately quite catastrophic.

  • Moderator blocks, fuel was spread

  • all around the immediate area.

  • If you look in this photo, it's rather difficult to see.

  • But at the bottom of that column of smoke

  • you can actually see the bottom up the biological shield.

  • Kind of gives you a sense of the scale

  • of the damage to the reactor.

  • After the explosion happened, actually none of the operators

  • believe the reactor breached confinement in any way.

  • They didn't really have an immediate way

  • of seeing what had happened.

  • So they open the door and went to the main turbo generator

  • building to investigate the damage.

  • They believed it was perhaps one or two ruptured fuel channels.

  • As it happened at, I believe the Leningrad,

  • I think it was the Leningrad power

  • station a few years earlier.

  • In the few seconds that they were there,

  • they received fatal doses and died in the hospital

  • in May of 1986.

  • This is a photo from control room of reactor 4,

  • showing a jammed control rod drive at the 6 meter position.

  • So this was probably a rod, let's see,

  • this is probably a rod coming up from the bottom, in that it,

  • seven meters would be all the way out.

  • Zero meters would be all the way in.

  • The initial response to this, despite the fact

  • that the reactor operators were not

  • yet dead, did realize that it was

  • a full breach of containment, was

  • the response was to an accident that was non-nuclear in nature.

  • So when the fire department got a call from the authority

  • at Chernobyl, the message that they received

  • was there's a fire at the reactor complex.

  • As a result, what they showed up with

  • was not equipment suitable for a hazmat situation in any way.

  • That said, there's pretty much nothing

  • that could shield anyone from the extremely high radiation

  • field that one would encounter around

  • the reactor in the immediate aftermath of the accident.

  • But nonetheless, they were extremely vulnerable.

  • It was night when this accident happened.

  • As I mentioned, this happened at 1:23 in the morning.

  • They actually couldn't see the extent of the accident.

  • And they initially believed that it was just

  • a fire on the roof of the turbo generator building.

  • They attempted to fight the fire.

  • And some of them actually succumb

  • to acute radiation poisoning, or acute radiation syndrome,

  • almost immediately.

  • A number of firefighters went up on the roof

  • and just didn't come back.

  • The aftermath of the accident, the cleanup

  • was handled by the Soviet Army.

  • The people that were involved in this

  • were known as the liquidators.

  • They would spend several minutes on the rooftop of the turbo

  • generator building, or up near where the reactor was,

  • the reactor containment building was.

  • And they would receive a, effectively a lifetime dose,

  • which I believe was, I believe their limit was 50 REM.

  • And that would be a couple of minutes up there.

  • Let's see, this photo doesn't show much evidence of it.

  • But I suppose it shows a little bit of evidence of it.

  • If you look around the bottom up the frame,

  • you can actually see a little bit

  • of hazing in kind of a periodic fashion.

  • Let's see if I can get my pointer on it here, here, here,

  • here, and here.

  • That's the gear that moves the film is actually

  • shielding the film from radiation

  • exposure at those points.

  • The radiation dose rate was so high up there

  • that most of the pictures that were taken just

  • didn't turn out whatsoever.

  • A few smarter photographers used a whole lot of lead

  • and were able to capture photos like this.

  • But nonetheless, the dose rates were tremendous.

  • The reactor structure itself was entombed in this thing

  • that we call the sarcophagus.

  • People in Ukraine call it the object shelter,

  • or the shelter object.

  • It was constructed in starting almost immediately

  • after the accident, basically to keep radioactive graphite

  • and fuel fragments from leaving the reactor structure

  • and contaminating any more land.

  • This is a photo from when it was under construction.

  • Basically what it consisted of were steel and concrete walls

  • that were erected around the reactor,

  • using a variety of technologies.

  • They at first attempted to use robots,

  • that were almost immediately rendered useless

  • by the high radiation field.

  • Later on, they ended up using quote "bio robots," people,

  • to move things into place.

  • As I've said before, a whole lot of people

  • died in this accident both immediately and after,

  • many during the construction of the sarcophagus.

  • Actually during the initial firefighting,

  • or yeah, the initial firefighting measures,

  • as the core remained burning for a number of weeks

  • after the accident, they attempted

  • to put it out with bags of sand dropped from helicopters.

  • And during that effort, a helicopter actually

  • ended up hitting one of the cranes

  • that they were attempting to use for this

  • and falling into the reactor, and a good portion

  • of its remains remain entombed within the sarcophagus,

  • from what I understand.

  • All right, so my visit to Chernobyl, why would anyone

  • ever want to go there?

  • The primary focus was to learn about

  • radiological decontamination at the site,

  • basically how is contamination control managed,

  • how do workers stay safe.

  • Mind you, there are 3,000 people that

  • go to work there every day.

  • And what are the strengths?

  • And what are the shortcomings of their radiological program?

  • It was seven days total, four of which were on site.

  • Other days were spent in Pripyat as well as

  • in some classroom training, which I've got great photos of.

  • So this is a slide stolen directly from the PowerPoint

  • that I was sent on day one.

  • But this was organized by three people, Carl Willis,

  • Erik Kambarian, and Ed Geist.

  • I've known Carl for a few years now.

  • He lives in Albuquerque, New Mexico

  • and is a radiation safety officer at a company

  • that, I think they do advanced energy storage technologies.

  • I'm not exactly sure.

  • Erik is a firefighter and specializes in radiation

  • emergency response.

  • And Edward works at the Rand Corporation

  • and does nuclear history and nuclear security research.

  • This is the team this year.

  • So we've got, let's start here.

  • This is Lucas.

  • He does environmental radiation monitoring.

  • That's me after having no sleep because I did a 22.611 p-set

  • the night before.

  • I know.

  • I looked so happy to be there.

  • This is Nathan.

  • Nathan builds organs, as in the musical instrument.

  • He was along because he's always been

  • interested in Chernobyl but didn't really have

  • any experience in the field.

  • This is Stanislaus.

  • Stanislaus was our guide from the Chernobyl authority.

  • He's been working at the plant since 1991

  • and is a fantastic resource for information.

  • This is Ed, who I believe I talked about earlier.

  • And this is Ryan Pierce.

  • I'm not really sure what he does.

  • This is Iris, who is a friend of Carl's and works in,

  • believe radiation oncology.

  • And then Danell Hogan, who's an educator based in Phoenix,

  • Arizona who works with the DOE.

  • By the way if you're wondering why we're all

  • wearing those absurd robes before we

  • were going to go in to another room

  • and change into basically coveralls, which

  • are easy to decontaminate.

  • One of the activities that we did

  • was real decontamination training.

  • So that is a truck from the Novarka work site,

  • which, by the way, that is me with a Geiger counter.

  • I'm surveying for contamination.

  • We then pressure washed the truck.

  • As it turns out, there's a very specific technique

  • one needs to use for pressure washing when you're dealing

  • with a contaminated object, so as to not blast contaminated

  • dirt up back onto the truck.

  • This was a very interesting experience and also

  • one that was very entertaining for the workers involved,

  • because they don't actually wear that when they're

  • doing decontamination because their respect for safety

  • protocols are, shall we say, a bit different.

  • So they got to see us where the absurd rubber

  • ducky suits while they stood by smoking and laughing at us.

  • I believe you can actually see the corner of that guy's jacket

  • back there.

  • And he's just wearing everyday clothes.

  • We also went on the new safe confinement work site.

  • So I haven't talked about it earlier in this presentation,

  • but I suppose I should have.

  • There is a object called the New Safe Confinement

  • Arch that consists of basically a giant stainless steel

  • structure on rails which is being slid over reactor 4

  • so as to prevent the spread of any sort of contamination

  • from it.

  • This is known as the New Safe Confinement, or NSC, arch.

  • It's been under construction since 2007.

  • And it just moved for the first time,

  • actually while I was there, so on the 12th of November.

  • It's supposed to last for 100 years.

  • And hopefully in that kind of time span

  • they'll be able to take apart what remains of the reactor.

  • So actually what you see here is the corner of the sarcophagus.

  • And then if you were to pan over this way a little bit,

  • you'd see the right set of tracks for the New Safe

  • Confinement Arch.

  • We also did some classroom training.

  • Admittedly, the classroom training

  • was the most disappointing part of this.

  • The instructors were not particularly

  • interested in showing us really anything

  • other than YouTube videos and other things that would just

  • waste our time.

  • That was the one part of this trip that I did not enjoy.

  • Regardless, we did get to learn a little bit

  • about the various hazmat getups that folks would

  • wear when working on site.

  • As I mentioned we also got to visit Pripyat,

  • which I have more photos of later,

  • as well as the reactor 4 control room, which

  • is inside the sarcophagus, which is quite a treat to visit.

  • The reactor 4 control room is not

  • terribly contaminated as a result of the decontamination

  • efforts.

  • During the accident, the dose rate

  • would have been somewhere in the range of 5 to 10 rem an hour.

  • But today, it's in the range of 10 mrem an hour.

  • This is the New Safe Confinement Arch

  • that I've been talking about.

  • This is actually a photo from 2015 with a clip art Statue

  • of Liberty on it, but to give you an idea of how huge

  • it is, 5 meters taller than the Statue of Liberty.

  • And it's on rails, which is interesting.

  • It's actually too big for wheels.

  • So it's not on rails like with wheels on them.

  • It's on rails with giant Teflon scoots.

  • This is the inside of the turbo generator hallway.

  • Remember that long building that I showed you

  • that connected reactors 1 and 2 and 3 and 4?

  • This is right outside the reactor 3 part of it.

  • There are-- I think I'll show you these photos later.

  • There are chunks of the turbine from reactor 4

  • that are down here in this area that are quite visibly

  • radioactive and are very easy to detect if one swings a Geiger

  • counter about.

  • Within Pripyat we also visited a hospital 126,

  • which is where the firefighters went immediately

  • after the accident, that is, the ones that made it off the roof.

  • This garment here, we're not exactly

  • sure what it was because none of us

  • were going to really touch it.

  • But we think it might have been part of a cover--

  • it would go under one's helmet--

  • was extremely radioactive.

  • It was contaminated with alpha, beta, and gamma,

  • which is fairly unusual.

  • Alpha contamination is fairly rare around the Chernobyl site,

  • and was somewhere around 50 to 75 mR an hour on contact.

  • I think I already showed you photos the control room.

  • Yep, unit 4, that's the cartogram,

  • so that would display various parameters of the reactor

  • for each fuel channel, depending on how one configured it.

  • That's an external photo of the sarcophagus.

  • And I think that's it for the PowerPoint slides.

  • I do have a bunch of photos though that I think

  • you will find interesting.

  • I apologize if it's a little disorganized.

  • This was put together relatively recently because, well, I

  • just got back from Chernobyl.

  • And then I went to a conference.

  • And then I came back here and tried to get work done.

  • Right, so these are in chronological order roughly.

  • I'll go through and hopefully tell you guys

  • a little bit about what the site's like.

  • MICHAEL SHORT: [INAUDIBLE].

  • JAKE HECLA: OK, so this is on day one.

  • We're driving to the Chernobyl nuclear power plant site.

  • That blue and white bus is pretty much

  • what everyone uses for transport around there.

  • All right, so we're not really supposed

  • to be taking photos in this area.

  • So everything is tilted because it's

  • taking them out the window with the camera like that.

  • That's the New Safe Confinement Arch.

  • It's in considerably better shape

  • than it was last year at this time.

  • They have done a fantastic job of putting it together.

  • It's actually almost a year ahead of schedule.

  • There it is, again.

  • You can see the sarcophagus with the new support wall,

  • which is that right there.

  • All right, so this is our excursion into Pripyat

  • on our second day.

  • So this is the group led by Stanislaus.

  • As you can see, there's not very much left.

  • Just in comparison to what we saw last year,

  • the number of buildings that had been taken apart

  • for scrap metal, illegally, of course, was pretty huge.

  • In, I don't know, 5 or 10 years, it's

  • going to be very difficult to see much of Pripyat at all,

  • frankly.

  • So this is a standard apartment block in Pripyat.

  • As you can see, a lot of broken windows.

  • A lot of bricks have fallen off.

  • These things are pretty dangerous.

  • A lot of tourists do go into them.

  • If one decides to do a tourist expedition to Chernobyl-- which

  • I don't particularly recommend-- don't

  • go in the apartment blocks.

  • This is on the way to one of the schools.

  • This is Lucas who has more detectors than anyone I've ever

  • met.

  • He was wearing 7 at the time.

  • So I had to take a photo of him.

  • This is Iris imitating some of the graffiti, which

  • unfortunately has popped up all over the place.

  • Pripyat itself is really decaying quickly.

  • As I've said, there's a huge problem with looting.

  • In addition, there's a huge problem

  • with graffiti and vandalism.

  • It's really depressing, honestly,

  • to go there and see how much has changed just in a year.

  • So despite my earlier warning, we

  • did go in an apartment block.

  • This is just a measurement showing

  • that the background up there actually is not terribly high.

  • Yeah, that's Iris, not particularly safety conscious

  • at times.

  • This gives you a good idea of how far away

  • Pripyat is from the reactor.

  • That is not very far, about two kilometers.

  • So you can see the New Safe Confinement Arch

  • to the top left of the detector.

  • Background there is about, in this particular apartment

  • block, at this particular time, was about four to five

  • times what you would see in downtown Cambridge.

  • There are wild animals in Pripyat

  • and the rest of the exclusion zone.

  • This is a huge problem.

  • So despite the fact that the cats are very cute

  • and the puppies are very cute, they also have rabies,

  • not all of them, but a very large number of them.

  • In 2009, five workers were injured by, I kid you not,

  • a rabid wolf.

  • There's a YouTube video of this you

  • can look up on your own time if you so wish.

  • This is because Ukraine doesn't have a lot of money.

  • So they have not been able to continue with their vaccination

  • program.

  • They actually use baits that have a rabies vaccine in them

  • to normally suppress rabies in wild animal populations.

  • But Ukraine doesn't have any money.

  • They killed the program about five years ago.

  • And as a result there's a huge, huge problem with,

  • especially rabid foxes.

  • Because everyone thinks foxes are cute, especially tourists.

  • And foxes, when they get rabies, some of them

  • go through a stage in which they appear to be very friendly.

  • As far as I know, no one has gotten

  • rabies from a rabid animal at Chernobyl.

  • But it's certainly a possibility.

  • So Stanislaus was being a very bad example by feeding one

  • of the wild cats.

  • So that's why I took a picture of it.

  • This is one of the many memorials

  • that you'll find in downtown Slavutych.

  • We stayed in the city that was built, effectively,

  • as a replacement for Pripyat.

  • It's actually a fantastic town.

  • I really enjoy Slavutych.

  • And as one might expect, there are memorials

  • everywhere because the entire population is basically

  • the folks that were removed from the town of Pripyat.

  • This is the train we would take every day.

  • Slavutych is separated from Pripyat

  • by a little isthmus of Belarus that drops down.

  • So that's bad, because you can't get a visa to Belarus.

  • It's not really a thing you can do as an American.

  • I mean, you can apply for one.

  • You'll just never hear back.

  • Belarus is Europe's last dictatorship.

  • And it's not some place one wants to go for any reason.

  • So when we would get on this train, the doors would shut.

  • We would go through Belarus and we would all

  • pray that didn't break down because then we

  • would have to spend some time to Belarus in prison.

  • But yeah, this is the train yard, bright and early.

  • The various zones on the reactor site for cleanliness,

  • so to speak, radiological cleanliness

  • are separated by these benches effectively,

  • that you have to step over, so that it reminds you that, hey,

  • this is the clean area.

  • You need to be wearing boot covers and at least

  • these garments in order to go here.

  • Sideways, for some reason, this is part of the--

  • all right, I don't know why these are all sideways.

  • But regardless, you get the picture.

  • If you notice on the top of the screen, which

  • should be the left of the screen,

  • let's see if I can rotate it.

  • That's a giant puddle of water.

  • This place is falling apart.

  • Despite the fact that they have money

  • from the European bank on reconstruction and development

  • for the New Safe Confinement Arch,

  • the Chernobyl site itself does not have a lot of money.

  • And as a result things are falling apart.

  • And the amount of contamination that

  • is getting into places where it very much shouldn't be,

  • like this quote "clean area," is fairly high.

  • That puddle of water was pretty toasty, something like 5 to 8

  • mR an hour on contact.

  • That's generally quite bad.

  • As I said, water is coming in everywhere.

  • And in this case they were using leg covers to catch the water.

  • Another one of the hallways that had water leak into it

  • and therefore all the lights are out.

  • That's the footwear which we were issued,

  • which breaks after walking about a kilometer, which is not

  • particularly encouraging if one wants to take their boots back.

  • Again, walking down the hallway, you

  • notice this gold corrugated material

  • that you see on the sides?

  • It's aluminum that is anodized.

  • And it's placed there because it covers up

  • all of the sheets of lead that were affixed to the wall.

  • What happened is in the aftermath of the accident,

  • the entire facility was just hopelessly contaminated.

  • And you can scrub all you want, but ultimately it's

  • very difficult to get radioactive contamination off

  • of things.

  • So what they ended up doing was getting it

  • down to a somewhat acceptable level,

  • and then fastening sheets of lead over it,

  • and then fastening this stuff over the top of that.

  • This is unit 2's control room.

  • So this is what a fully fleshed-out control

  • room looks like.

  • Unit 2 were shut down in 2000.

  • The reactors actually continued operating

  • after the 1986 Chernobyl accident

  • because Ukraine was in such desperate need of power.

  • As a result, the fuel is still fairly hot.

  • It's producing a reasonable amount of decay heat.

  • And there is a crew that sits in the control room

  • at all times monitoring it.

  • That's Nathan.

  • This is actually, I took a picture of this

  • because it's a very good diagram of the Chernobyl reactor

  • that's simplified.

  • It shows the core and the relative locations

  • of these steam, water separators.

  • OK, as I said, there is a team that stays in there.

  • So there are people that work on site and work in the reactor

  • control rooms, which I have to imagine

  • has to be a bit of a surreal job.

  • This is inside the main, inside the turbo generator hall.

  • Those chunks that you see here are from the turbo generator

  • of reactor 4.

  • So they're quite contaminated and quite easy to detect.

  • Actually, there is a good story behind this.

  • So we were trying to figure out exactly what was

  • making the dose rate so high in the area when we were up there.

  • So we got a group of us to stand in a circle, minus one person.

  • So there's a gap.

  • We got a person in the center with a scintillator.

  • And we all kind of rotated around

  • until we found in which direction

  • the scintillator reading was high enough, so basically made

  • like a 2 pi meat shield.

  • It worked fairly well.

  • It thoroughly baffled all of the guides that were with us.

  • They were like, what are you doing linking arms

  • and spinning around.

  • Regardless, that is a good way to find sources

  • if you're in a pinch.

  • This is looking the other direction

  • from that same vantage point as in the last photo.

  • Behind those walls with a little radiation signs on them

  • are chunks of the ventilation stack, which is fairly iconic.

  • They've been fairly well decontaminated.

  • At that fence area, the dose rate or more accurately

  • exposure rate, was 10 mR an hour.

  • And yeah, that's another close up photo of it.

  • And I managed to sneak by phone over the top of it

  • and get a good shot.

  • Unfortunately, none of the pieces are uncovered.

  • I would really like to see the orange and white

  • of the ventilation stack.

  • But I did not.

  • Again, same shot, slightly different

  • shot of the turbo generator hallway looking in the unit

  • 1 2 direction.

  • More detritus, oh here's a slightly better close

  • up of those components.

  • One of the interesting things I found out about the facility

  • is way that access is controlled.

  • So instead of having an RFID card or something like that,

  • they've got cameras and operators.

  • So what you see here is a camera.

  • So Stanislaus would scan a badge that would automatically call

  • someone who is an operator.

  • Stanislaus would say, hey, I'm at this door.

  • I want to go into this location.

  • Will you let me in?

  • And then they would look at the camera,

  • determine that yes, that is Stanislaus.

  • He does want to go into this area.

  • And then they would approve it and let him through.

  • Walking through the corridors of the sarcophagus.

  • You can actually see up here those lead sheets

  • I was talking about.

  • I don't know how thick they are on there,

  • or how close they are to falling off, for that matter.

  • But I'm sure several thousand pounds of lead

  • is right there alone.

  • These are main circulating pumps, about one-half

  • of the main circulating pumps for reactor 2.

  • And each one of these things takes

  • something around, something around 40 megawatts

  • to actually operate.

  • These are aligned differently and are

  • of a different type than the ones used in reactor 4

  • because reactors 1 and 2 were of an earlier design.

  • Ironically enough, reactors 1 and 2 actually

  • don't have all of the safety measures

  • that reactor 4 does, which is a bit terrifying to think of.

  • Yet more photos, right, as I said, dog problem at Chernobyl.

  • This is right outside the entrance to a clean facility.

  • And occasionally these dogs would wander in.

  • Unfortunately dogs are large furry piles of easily airborne

  • contamination.

  • So they would walk in.

  • People would go to shoo them out.

  • They would shake their coats or whatever.

  • And then clean up on aisle three,

  • because now there's contamination everywhere.

  • More sad looking puppies.

  • New Safe Confinement, yet again, to give you an idea of scale,

  • let's play find the workers.

  • Those are workers right there.

  • Can you guys see them?

  • AUDIENCE: Barely.

  • JAKE HECLA: Yeah, they're really, really small

  • next to this facility.

  • AUDIENCE: [INAUDIBLE].

  • JAKE HECLA: Yeah, I think I've got a slightly better shot

  • here.

  • That's a guy right there.

  • There's also another dude right here.

  • Yeah, this place is, or this structure

  • is absolutely enormous.

  • It's really hard to wrap your head

  • around exactly how large it is.

  • So this is in an area called the local zone.

  • So it's the immediate several hundred meters

  • surrounding the reactor.

  • As you can see, the hazmat equipment

  • that we're wearing there is significantly

  • different from what we would wear inside the reactor

  • or inside the sarcophagus, mostly

  • because the threat from dust in this area is pretty huge.

  • As you can see, we're walking on fill.

  • It's actually meters and meters of fill

  • because the ground was so contaminated

  • that they scraped it away, put fill in there,

  • put fill on top of that because just the residual contamination

  • was enough to make it hazardous to use as a work site.

  • Though they're not shown in this image,

  • or I believe any images here, there

  • are little concrete and lead structures

  • that these workers take breaks behind

  • because you have a dose limit that is enforced

  • while you're working there.

  • And if you're going to take a smoke

  • break, as a huge fraction of the population of Ukraine

  • smokes, or you're going to take a break of another sort,

  • they don't want you racking up dose during that time.

  • So you basically hide in a little concrete shack

  • for a while with a few inches of lead

  • between you and the reactor.

  • Yet another shot inside the sarcophagus,

  • Ed explaining something about which I'm not sure.

  • As you can see these places are not exactly

  • in the best condition on the inside.

  • And one thing that did concern me a lot

  • was the amount of dust that was very, very

  • easy to kick up in the area.

  • This is inside control room of reactor 4.

  • Selfie, which I didn't mean to have in this album.

  • Control room 4 hasn't changed a whole lot since last year.

  • But there is a dividing wall that

  • actually separates reactors 3 and 4 that's

  • being put together.

  • And it cuts right through the edge of the fourth control

  • room.

  • And for a while, we actually didn't know whether or not

  • we were going to be able to visit it at all because

  • of ongoing construction.

  • I'm very glad that we were able to.

  • Most of the instruments have been removed.

  • It's unclear as to why.

  • We've been told that some of it was because of contamination.

  • But the pattern doesn't really make sense.

  • This is the reactor control room cartogram, excuse me,

  • reactor core cartogram, which, as I said

  • was lit and could display various parameters regarding

  • the various fuel channels.

  • There is only two control rod indicator, well, yeah.

  • There are really only these control rod indicators left.

  • And we believe that actually some of these

  • might not be original.

  • Someone might have stolen the real one

  • and put another one back.

  • I don't have any evidence to support it.

  • But I suspect that there's significant looting that

  • happens in here.

  • This is a rather entertaining photo.

  • That means smoking area.

  • That's in the control room.

  • You shouldn't be smoking.

  • You shouldn't take your mask off for any reason.

  • That's a high gamma radiation warning sign.

  • It was in fact, not that high of a dose rate,

  • somewhere in the range of 30 mR an hour.

  • We also explored a little bit outside of the more formal part

  • of the reactor premises, namely we

  • went to this place called Buriakivka 2, which

  • is a burial facility for waste from the reactor,

  • not waste as in nuclear waste but waste is in chunks of metal

  • and other things that are contaminated and therefore

  • removed when the New Safe Confinement Arch was being

  • built, or when, let's say, they were building the separation

  • wall between reactors 3 and 4.

  • And there were some incredibly hot spots.

  • So I might, I think I have some more photos later.

  • But just under that little triangle,

  • the dose rate was 150 mR an hour, so 0.15 rem an hour.

  • It's extremely high.

  • And that was just in a field basically, not controlled, not

  • patrolled, no warning signs.

  • Getting dressed up, lots of fun.

  • That was the truck we were sent to decontaminate.

  • Honestly it wasn't particularly contaminated

  • in the first place.

  • They weren't going to give us real fun things to play with.

  • That's all of us.

  • And then as you notice, the real workers

  • here are not wearing even a fraction of what we are.

  • More decontamination, yeah, see, barely anything.

  • These are chunks of metal that have come out of the reactor.

  • We're not exactly sure what part, what parts they are.

  • No one was really able to answer our questions about them.

  • But they were also rather contaminated,

  • somewhere in the range of 50 to 75 mR

  • an hour on contact in some spots.

  • More photos of Chernobyl, or of Chernobyl from Pripyat.

  • MICHAEL SHORT: Dr. Jake, I want to take a quick break

  • and ask folks if they have any questions on what

  • the experience was like [INAUDIBLE]..

  • JAKE HECLA: Yes?

  • AUDIENCE: Did you suffer any adverse health

  • effects or anything?

  • JAKE HECLA: Only the cold I picked up on the way back.

  • The total dose that I received on this entire expedition,

  • minus the flights there and back, was 0.6 millisieverts.

  • So effectively, nothing.

  • MICHAEL SHORT: [INAUDIBLE].

  • JAKE HECLA: Well, all of the high radiation areas

  • that we were in, we were encouraged to walk quickly,

  • is basically what it comes down to.

  • The time portion of time, distance, and shielding

  • was emphasized.

  • Further questions?

  • Yeah.

  • AUDIENCE: Are there [INAUDIBLE] radiation area versus

  • [INAUDIBLE].

  • Do they use the same levels [INAUDIBLE]??

  • JAKE HECLA: No, radiological control in Ukraine

  • is a totally different game than it is in the US.

  • There are the same types of controls

  • that exist in the US just don't exist at that site.

  • For areas that are immediately dangerous to your health,

  • you know, 10 rad an hour, something

  • like that, from what I understand that there

  • are locked doors that prevent one from accessing those

  • accidentally.

  • And there are warning signs in a variety of locations.

  • But I don't think that there is a the same standardization

  • of 5 mR an hours is a radiation area, et cetera, et cetera.

  • Yeah.

  • Further?

  • MICHAEL SHORT: And are folks still going

  • to be running these tours pretty continuously?

  • JAKE HECLA: No.

  • You won't be able to see the sarcophagus itself because it

  • will be contained within the New Safe Confinement Arch

  • pretty much now.

  • It's 75, right, let's see.

  • Last I checked, the New Safe Confinement Arch

  • was 75 percent of the way over the reactor itself.

  • Regular tourist visits to Pripyat

  • will continue to happen.

  • This program that I went on is something very special.

  • Carl, Ed, and Erik have done this type of thing once before.

  • That was the trip I went on last year.

  • And they intend on doing it once a year as long as they can.

  • But that's pretty much your only opportunity

  • to get that kind of access to the reactor.

  • It takes a lot of work.

  • MICHAEL SHORT: Anyone else have questions for Jake?

  • It's rare to meet someone that's actually gone to Chernobyl to

  • [INAUDIBLE].

  • Yeah?

  • AUDIENCE: Do you think it's haunted?

  • JAKE HECLA: No.

  • There's a rather haunting location, though,

  • the Khodemchuk Memorial.

  • So when the accident happened there was one guy who was--

  • depending on how you look at it, either lucky or unlucky--

  • in that he wasn't killed by radiation poisoning.

  • He was killed by being flattened in the explosion.

  • And his remains are within the reactor

  • and within the sarcophagus, never really recovered him.

  • Better than dying of radiation poisoning.

  • But nonetheless, not a fantastic way to go.

  • The memorial that is within the sarcophagus

  • is pretty interesting to visit, and rather somber.

  • Makes you reflect a little bit on the enormous human toll

  • that the accident had.

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