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visit MIT OpenCourseWare at ocw.mit.edu. 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.
