Nova (1974–…): Season 42, Episode 22 - Nuclear Meltdown Disaster - full transcript
NARRATOR:
Japan's most powerful
earthquake ever...
(screaming)
...triggers a monster tsunami.
NARRATOR:
Fear washes over the nation.
NARRATOR:
But that's just the beginning.
Ten nuclear reactors
at two power plants
are crippled,
threatening the unimaginable.
(translated):
If Tokyo needed
to be evacuated,
I feared the entire nation
of Japan
would be paralyzed by chaos.
(translated):
It became darker and darker.
A terrifying situation.
We were fighting
an invisible enemy,
out-of-control reactors.
NARRATOR:
What will it take
to save the country
from lethal radiation?
CHUCK CASTO:
Mankind has never faced
the forces of physics
and the forces of nature
those people faced.
NARRATOR:
"Nuclear Meltdown Disaster,"
right now on NOVA.
Major funding for NOVA is
provided by the following...
We love science.
Supporting NOVA and promoting
public understanding of science.
And the Corporation
for Public Broadcasting.
And by PBS viewers like you.
Thank you.
And Millicent Bell,
through the Millicent
and Eugene Bell Foundation.
Additional funding from the
Montgomery Family Foundation.
NARRATOR:
This is the road to nowhere,
a once-thriving place
in one of the most prosperous
countries on Earth...
Japan.
Radioactive Japan.
Time stood still here
on March 11, 2011.
Houses that aren't homes.
Schools that are silent.
Stores shuttered.
Towns without people.
Past the checkpoints,
the scans,
and the meticulous suit-up,
layer upon layer upon layer
of protection
is the place we simply know
as Fukushima...
...site of three
nuclear reactor meltdowns.
(translated):
This is called the Central
Control Room.
All of the equipment
at the power plant
is operated from here.
NARRATOR:
He is a nuclear plant operator.
This is where
he has always worked.
He used to live nearby,
but now he too cannot go home.
He and his co-workers
are ashamed,
scorned by the neighbors
they once had.
OPERATOR (translated):
We've been through so much
in this control room.
It's hard to put into words.
NARRATOR:
He was here when it happened.
Now he is hoping to make amends
by helping clean up
the toxic mess.
OPERATOR (translated):
Four years ago,
this room was completely dark.
We had only small fluorescent
lights and flashlights.
We had given up
on our own survival.
Now, talking to you
with the lights on,
it seems like a lifetime ago.
NARRATOR:
This is the story
of the Fukushima meltdowns.
The infamous events at Fukushima
Daiichi, or number one...
(alarm blaring)
...told by those who were there
and risked everything.
NARRATOR:
And the lesser-known story
of its sister plant
seven miles away:
Fukushima Daini, or number two.
It faced the same onslaught
and challenges,
but thanks to a little luck
and a herculean effort,
it was saved
from ending up like this.
March 11, a bad day for Japan
and the world,
could have been so much worse.
NARRATOR:
The inevitable came
without warning at 2:46 p.m.
Two giant pieces
of the earth's crust,
tectonic plates,
move suddenly and violently.
One pushes down,
causing the plate above it
to spring upward like a catapult
along a 300 mile fault line .
In a nation all too familiar
with earthquakes,
it is the largest ever recorded:
magnitude nine.
Propagating outward
at 9,000 miles an hour,
record-breaking seismic waves
careen toward land
and the ten nuclear reactors
at the two Fukushima plant
all of them designed
by General Electric,
owned and operated by
the largest utility in Japan--
the Tokyo Electric
Power Company--
TEPCO.
They are there to feed
the insatiable energy needs
of Tokyo.
(translated):
Suddenly, I heard
the earth rumble,
like a fierce growl.
It was an extremely
intense earthquake.
But it wasn't only strong,
it was also terribly long.
NARRATOR:
An American nuclear reactor
service technician,
Carl Pillitteri, is there
doing some upgrades.
It was just one big hammer.
(screaming)
The entire building was moving.
Everything was coming down.
The lights were crashing
everywhere.
And it just got worse
from there, actually.
In one nanosecond, just
the entire floor went black.
OPERATOR (translated):
The shaking was like nothing
I had experienced.
The operators either held
onto that bar or crouched down.
That's how we endured
the earthquake.
INAGAKI (translated):
I just wondered,
"How long is this going
to continue?"
NARRATOR:
It lasted six minutes.
Takeyuki Inagaki
is general manager
of the maintenance department
for Units 1 through 4
at Daiichi.
He reports directly to the
superintendent, Masao Yoshida.
Both men have spent
their entire careers at TEPCO.
Inagaki worries about his wife
and two sons.
(translated):
When the earthquake hit,
I think I sent one email
to my wife explaining that
I didn't think I'd be able
to come home for some time.
After sending that email,
we became unable
to contact the outside.
We couldn't even make calls.
(clicking)
NARRATOR:
Seismometers at nuclear plants
are designed to trigger
an automatic emergency response
after an earthquake.
(shouting)
NARRATOR:
Power plant operators
routinely drill for this,
but it is still a risky,
tense event.
Called a SCRAM, it is designed
to put the brakes
on the nuclear chain reaction
of sustained fission.
A nuclear reactor
is fueled by uranium,
an element that naturally
splits apart,
releasing neutrons.
But uranium fission
can induce more fission.
When a loose neutron fires
into a nearby uranium nucleus,
it becomes unstable
and quickly splits.
Each time an atom splits,
it generates heat.
To make fission robust enough
to generate power,
uranium is enriched,
shaped into pellets,
and then stacked in long tubes
called fuel rods.
This ensures
lots of uranium atoms
are close enough to each other
to allow
a healthy chain reaction.
To manage the rate
of the reaction,
control rods
that absorb neutrons
are moved in and out of spaces
among the fuel.
During a SCRAM, the control rods
are pushed all the way in,
terminating the chain reaction.
By 3:02, operators at Daiichi
confirm the three reactors
that were online
have successfully SCRAM-ed.
And at Fukushima Daini,
all four reactors
running full throttle
also automatically shut down
safely.
Even though
the nuclear chain reaction
has now abruptly stopped,
the uranium fuel rods
remain very hot.
It's called decay heat.
DAVE LOCHBAUM:
The nuclear chain reaction
was stopped within seconds,
but the decay heat
continued to be a problem.
It takes approximately
20 to 24 hours
for the systems
to cool the reactor down
to less than 212 degrees
and achieve what's called
"cold shutdown."
NARRATOR:
At its core,
a nuclear power plant
is not unlike a pressure cooker
on a stove.
Water is heated
to the boiling point,
creating steam.
And steam under pressure
turns turbines,
generating electricity.
The complexity and cost
of nuclear energy
is about keeping the radioactive
genie in the bottle.
So the uranium fuel
sits inside rods underwater
in a steel pressure vessel
surrounded by a concrete
and steel containment structure
inside a reactor building.
All those layers of protection
are there
in case the water stops flowing.
If that happens,
it quickly boils away,
exposing the fuel,
and it melts,
turning into radioactive magma.
Unchecked, it will melt right
through the steel reactor vessel
and on to the concrete
and steel containment structure
that surrounds it.
So at the Fukushima plants now,
it is critical
that the electric water pumps
and valves keep running
for the reactor core
to safely cool down.
Power normally comes
from the electric grid,
and the earthquake
has caused a blackout.
But there is a plan B.
(whirring)
The plant is equipped
with diesel electric generators
to provide power
in an emergency.
They start automatically,
as they're designed to do.
LOCHBAUM:
If it had only been
the earthquake,
we wouldn't be here today.
The safety systems
were doing their thing,
the reactor cores
were being cooled,
and things were going
pretty well.
NARRATOR:
When the sea floor
suddenly moves upward
during the earthquake,
it causes the water
near the epicenter
to rise with it.
The giant swell is the start
of a tsunami.
(alarm blaring)
Forecasters issue
a tsunami warning.
They predict ten-foot-high waves
in Fukushima Prefecture.
The main buildings
at Daiichi and Daini
are about 30 feet
above sea level,
so no one worries much
about a tsunami.
NARRATOR:
And then, at 3:27 p.m...
the first of seven
giant waves
crashes over the seawall.
PILLITTERI:
Then I saw the tsunami coming.
I was on top of that hill,
and I wondered
if I was high enough.
This thing was, you know...
It was huge.
NARRATOR:
The tallest surge of water
is nearly 50 feet high,
nearly three times higher
than the seawall.
OPERATOR (translated):
I assumed there would be
a tsunami,
but not one 50 or 55 feet high.
I couldn't even imagine
a tsunami like that.
NARRATOR:
Fukushima Daiichi is inundated.
Two workers drown,
trapped in the basement
of the number four
turbine building.
Six generators,
along with the wiring,
switches, and breakers
connecting them to the plant
are located in the basements
of the turbine buildings
for Units 1 through 4.
The flood waters
destroy them all.
Two additional generators
behind Unit 4 are high and dry,
but their switching gear
is in the basement,
ruined by the seawater.
The generators would be useless.
Meanwhile, seven miles
to the south
at the other Fukushima plant--
Daini, or number two--
the crisis is equally dire.
The big waves roll in,
swamping key motors, wiring,
pumps, and generators.
NAOHIRO MASUDA (translated):
Immediately
after the tsunami hit,
this room lost power.
That's when I realized something
very serious had happened.
NARRATOR:
Naohiro Masuda
is the plant superintendent
on that fateful day.
He began his career here
at Daini,
reporting for duty in 1982
while it was still being built.
He knows it as well as anyone.
MASUDA:
This building is 40 feet
above sea level,
and if there was
a power outage here,
I imagined most of the buildings
near the sea
were damaged by the tsunami.
From that point on,
we knew we were in trouble.
NARRATOR:
Operators in the control rooms
give Masuda very bad news:
Units 1, 2, and 4
no longer have any operative
cooling systems.
(translated):
In nuclear power, we say,
"Stop, cool, and contain."
These are the three
most important functions.
When I realized that
we had lost cooling,
I knew the situation
was extremely serious.
NARRATOR:
But what needs to be fixed?
And how?
He orders a team
of about 40 workers
to go out
and inspect the damage.
(translated):
There were several hundred
aftershocks that day.
I really hesitated
to give the order
to send people out on-site.
NARRATOR:
They arrive in the rooms
housing electric motors
that run the pumps
that draw seawater
to cool the reactors.
(translated):
Cars had been washed
right up to the door,
and there were huge piles
of debris.
"How could you have sent us
to such a place?" they said.
NARRATOR:
Today, they have preserved some
of the evidence of the flood
that wiped out the motors
and their wiring.
MASUDA (translated):
Electrical supply systems
are located in this room.
The tsunami came up to here.
NARRATOR:
Back at Daiichi,
Reactors 1 through 4
are now in total darkness,
and things are quickly spiraling
out of control.
OPERATOR (translated):
We were in the middle
of dealing with the accident.
Then, all at once,
the lamps went out.
All sorts of alarms
were going off.
All of those went out.
Basically, a station blackout.
NARRATOR:
"Station blackout"--
the two most dreaded words
in the world
of nuclear power generation.
At Fukushima Daiichi,
Reactors 1 and 2 not only lose
the alternating current
that powers the pumps
and valves,
but also the direct current
that keep the instruments
working.
(translated):
It became darker and darker,
a terrifying situation.
And the operators weren't sure
what was happening.
We couldn't even tell
if there was water
in the nuclear reactors.
(translated):
We were at the starting line
of a race,
but we didn't know
if we'd need to run 100 yards
or if we'd need to run
a marathon.
NARRATOR:
The oldest reactor at the site
is Unit 1.
It began operation in 1971
and is equipped with outmoded
last-resort cooling systems
called isolation condensers.
LOCHBAUM:
The steam being produced
by the hot reactor core
was routed
into this large tank of water.
The water would cool the steam,
convert it back into water,
and it would drain back
into the reactor core
to be recycled
over and over again.
NARRATOR:
It is a passive system designed
to work on natural circulation
without any electrical power
at all.
So, is it working?
In the darkened control room,
they don't have a clue.
What they did not know
at the time
is valves
for the isolation condensers
are designed to automatically
close during a power failure,
stopping the flow
of steam and water.
When the isolation condensers
failed on Unit 1,
the reactor water level
just started boiling away
because it was no longer
being cooled and maintained
by the isolation condensers.
NARRATOR:
If the isolation condensers
are working properly,
vents on the side
of the reactor building
would be releasing
huge amounts of steam.
CHUCK CASTO:
There was steam coming out
of the discharge of it,
but they didn't realize
it wasn't sufficient.
So they thought they had
more time than they did.
NARRATOR:
Now, there is nothing
to stop the meltdown.
At 3:42 p.m., 15 minutes after
the tsunami waves rolled in,
TEPCO notifies the national
and local governments
that there is a "special event"
at the plant.
Actually, it is an emergency
that has never been envisioned.
FUKURA (translated):
It was a situation
that hadn't been anticipated.
We couldn't use
the procedure manuals.
OPERATOR (translated):
What was happening
was beyond what we trained for
on a daily basis.
Using what little information
we had,
we had to decide immediately,
"What can we do?
What should we do?"
It was a race against time.
NARRATOR:
They desperately need power,
but from where?
TEPCO dispatches
generator trucks,
but they are slowed by
earthquake and tsunami wreckage.
When they finally arrive
late on the 11th,
damage to the plant's
electrical system
makes it all but impossible
to connect them.
So they must improvise,
hoping to jury rig their
dead instruments back to life
by raiding the parking lots,
grabbing as many batteries
as they can from buses and cars.
INAGAKI (translated):
It took several hours
to figure out
how to connect the batteries.
They had the schematic
wiring diagram,
and they were furiously
examining it for several hours.
We ended up wasting
a lot of time.
NARRATOR:
Meanwhile, the water is
boiling away fast in Unit 1.
But how fast?
Six hours after the tsunami,
at 9:19 p.m.,
they finally get the batteries
and some portable
generators rigged
so the instruments
can flicker on.
The gauges show the water level
in Reactor 1,
normally 20 feet above the top
of the uranium fuel,
is now only eight inches
above it.
They pencil in a running record
of the water levels
right beside the gauge.
But the pressure in the vessel
is so high
it causes inaccurate
instrument readings.
They learn later
the uranium fuel
had actually been exposed
for three hours.
LOCHBAUM:
It's becoming more like
a lava flow from a volcano.
So it overheated, melted,
released radioactive contents,
and started falling into the
bottom of the reactor vessel.
NARRATOR:
In Tokyo, Japan's
prime minister, Naoto Kan,
worries that he might have
to order a mass evacuation
from Fukushima
all the way to Tokyo:
50 million people.
(translated):
If Tokyo had to be evacuated,
I feared
the entire nation of Japan
would be paralyzed by chaos
for quite a long time.
NARRATOR:
At 9:23 p.m., he orders everyone
living within two miles of
Daiichi to evacuate immediately
so TEPCO can prepare
to vent some steam--
radioactive steam.
At this stage,
radioactive iodine-131
is the isotope
of greatest concern.
It is linked to thyroid cancer.
Children are most vulnerable.
INAGAKI (translated):
We knew we had to vent,
but the question was, "How?"
There was no electricity,
and the valve was pneumatic.
We needed compressed air
from a compressor to open it,
but we didn't even have that.
NARRATOR:
Kan becomes increasingly
frustrated and impatient.
KAN (translated):
Even though we approved it,
many hours went by
and there was still no venting.
We asked them why.
A specialist from TEPCO told me,
"I don't know the reason."
Much of the information
he was getting
from his government
and the utility
turned out not to be true,
and he had no source
of independent knowledge
of what was going on
in those reactors.
NARRATOR:
Kan decides the only way
to know for sure is to go there,
and so early on the morning
of March 12,
he flies to Fukushima Daiichi.
He passes over mile upon mile
of utter devastation
from the earthquake and tsunami.
Nearly 16,000 are dead.
He lands at Daiichi
just after 7:00,
about 15 hours
after the tsunami.
KAN (translated):
I met with Superintendent
Yoshida for 45 minutes.
While he explained
the situation on-site,
I could see that he was a person
who could be trusted.
NARRATOR:
The prime minister endorses
the superintendent and his plan.
Yoshida vows to begin venting
at 9:00 a.m.
But there is much to do
and much to consider.
INAGAKI (translated):
To go into a pitch-black
reactor building
with high pressure levels,
I don't know if I should say it,
but it felt like we were putting
together a suicide squad.
NARRATOR:
To open the vent, they need
to manually turn two valves:
one in the basement
and another on the second floor.
At 9:04 a.m., a pair of workers
makes their way
through a dark labyrinth
to the second floor
of the Reactor 1 building.
It takes them 11 minutes
to open the valve.
Nine minutes later
a second team heads
for the valve in the basement.
They get to a point about midway
and the radiation is higher
than they thought they'd get.
They basically had drawn up,
"If radiation gets to this
point, we'll go back."
Well, they got to that point
before they got to the valves.
NARRATOR:
They abort their mission.
In the Emergency Response
Center, they realize
they must find a way to open
the vent remotely.
They scramble to find an air
compressor that can be attached
to the pipe that blasts
the valve open.
Finally, at 2:50 p.m.,
steam starts rising
from the exhaust tower
and the pressure starts
dropping.
Could the worst be over?
Actually, it is just
about to begin.
At Daini, where the power
is still out
and the reactors
are getting hotter,
there is a stroke of luck.
There is power inside the
radiation waste building
behind Reactor 1.
But they need it down
by the water.
Naohiro Masuda decides
to lay cables,
hoping to restore cooling
to the reactors.
Each of the four reactors needs
three operative pump motors.
They need to lay five-and-a-half
miles of cable
to connect them all.
He needs supplies urgently--
at least 50 big spools
of heavy-duty cable.
Masuda orders the cable,
but the shipment is delayed.
(translated): The police were
busy redirecting traffic
for evacuations
and when the truck hit those
detours it wound up going
in the completely wrong
direction.
NARRATOR:
While they wait at Daini,
the crisis is getting
much worse at Daiichi.
Uranium fuel rods are encased
in zirconium.
LOCHBAUM:
If it gets too warm,
there's a chemical reaction
between the zirconium
and the water or steam
to produce large amounts
of hydrogen.
NARRATOR:
A containment structure
on a boiling water reactor
is sealed with a dome-shaped top
that is removed for refueling.
The pressure in Reactor 1
is now so high
that it slightly lifts the top.
The hydrogen escapes
through the gap
and into the reactor building,
where it mixes with air.
It would be just a matter of
time before a spark would ignite
the highly flammable gas.
It is 3:36 p.m.
OPERATOR (translated):
Suddenly there was an upward
thrust, an impact that seemed
to push the whole building
upward
and it became completely dark.
(translated): I thought it was
just another aftershock,
but we all sensed something
was very wrong.
(translated): Then I was told
by headquarters
that the top of the reactor
building
was completely destroyed.
When I heard that,
I was shocked.
NARRATOR:
It is a devastating setback.
INAGAKI (translated):
I think that most of us
working at the time
didn't feel like we were going
to make it out alive.
NARRATOR:
At Daini, workers are preparing
to lay the heavy cables
when they get word
of the explosion at Daiichi.
MASUDA (translated):
After the explosion, I had
everyone outside come back
into the Emergency
Response Room.
There were 500 to 600 people
in the room.
I said, "Please trust me.
"I definitely won't do anything
to harm you,
"but Fukushima Daini is still
in trouble
and I need you to do your best."
NARRATOR:
The cables arrive
on the morning of the 13th.
Finally, the heavy lifting
to save Fukushima Daini begins.
(translated): These were
large-capacity motors,
several hundred amperes,
so the cables were fairly thick.
Each person had to walk
while carrying around
35 pounds of cable.
NARRATOR:
It is a race against time
and physics.
(translated): Normally, If you
wanted to lay that much cable,
it would take you about a month.
I didn't actually think
it was possible
in the amount of time
that we had.
YUTAKA (translated):
A total of around 200 workers
were involved.
We swapped people out
when they got exhausted.
NARRATOR:
In the midst of this, Masuda is
running out of fresh water
to cool his crippled reactors.
He asks TEPCO headquarters
for a shipment.
MASUDA (translated):
I asked Tokyo for 4,000
tons of water,
but instead they delivered
4,000 liters
of bottled drinking water.
That made me realize that we
were on our own.
We couldn't count on Tokyo.
So we started looking for water.
NARRATOR:
He remembers a creek
used as a water supply
during construction
of the plant.
Workers repair
the leaky old pipe
with a scavenged bicycle tube.
At Daiichi, events are still
overtaking them.
As the dust settles at Unit 1,
they learn five workers
are injured.
With freshwater reservoirs
exhausted,
they scramble to inject seawater
into the reactors.
By 7:04 p.m., success.
But using corrosive seawater
means the reactors will surely
be destroyed.
TEPCO headquarters tells
Superintendent Yoshida to stop
while they seek
government approval.
LOCHBAUM:
So Yoshida does
this very dramatic thing
where on the video conference,
he orders the people
to stop the seawater injection.
Before that, he called them over
and said,
"I'm going to order you to stop
the seawater injection.
"Ignore that.
"That's just for Tokyo.
You continue seawater
injection."
(translated):
Personally, I think the decision
that Yoshida made
was the right one.
(translated): If we had stopped
the seawater injection
at that point, things would
have been much worse.
(translated): In the meantime,
Unit 3 was becoming unstable.
Now our mission was "Don't let
Unit 3 turn into Unit 1."
NARRATOR:
With no battery power,
they are unable to open the
valves to begin venting Unit 3.
And there are no handles
on these valves.
So they grab car batteries,
hoping to open them
from the control room.
By 9:00 a.m. Sunday, March 13,
the Unit 3 reactor core
is exposed and melting.
The pressure keeps rising.
Fearing another hydrogen
explosion,
Yoshida orders workers
to retreat
to the Emergency Response Center
early on the morning
of March 14.
But the pressure plateaus and he
lifts the order an hour later.
INAGAKI (translated):
We alternated between deploying
and pulling back workers
because we were afraid of
another hydrogen explosion.
Unfortunately, we had close
to 50 people positioned
around Unit 3
when the explosion happened.
NARRATOR:
It is 11:01, March 14.
INAGAKI (translated):
Since there were so many people
out there,
I was really afraid
for their safety.
"It's very possible someone was
killed," I thought to myself.
Then, one by one,
people started to trickle back.
They were all very pale in the
face and some were bleeding.
NARRATOR:
When Unit 3 explodes,
11 workers are injured.
Amazingly, no one is killed.
And when we finally accounted
for everyone,
that's when we noticed the water
level in Unit 2 was dropping.
NARRATOR:
It seems inevitable that Unit 2
will be the next to blow.
At noon on March 14, an hour
after the explosion at Unit 3,
the water covering
the hot radioactive fuel
begins to drop precipitously.
An hour and a half later,
the emergency backup
cooling system fails.
Superintendent Yoshida quietly
tells a few trusted workers
to prepare buses
for an evacuation,
but for now he has no choice
but to order his men
back into harm's way.
INAGAKI:
After the explosion of Unit 3,
he begged us to again go
to the field to save Unit 2.
It was very impressive.
NARRATOR:
But by 6:22 p.m.,
the water is gone.
The uranium fuel is completely
uncovered and melting.
Again they try to use car
batteries to open the vents
and relieve some pressure.
No luck.
(translated): From the 14th
until early in the morning
on the 15th,
it was really...
how can I describe it?
It was like being in hell.
NARRATOR:
As day breaks on the morning
of March 15,
they hear a loud explosion.
(explosion)
But it is not what they dread.
It is a complete surprise.
There has been
an explosion in Unit 4.
But this reactor was shut down
for maintenance
when the tsunami hit.
What could have happened there?
And what saved Unit 2
from blowing up?
The investigation
will have to wait.
Superintendent Yoshida orders
an immediate evacuation
of 650 workers.
He and nearly 70 supervisors
would stay.
In the confusion, they become
known as the "Fukushima 50."
(translated):
We were fighting an invisible
enemy, out-of-control reactors.
From that perspective,
it was like fighting a war.
NARRATOR:
It is midnight on the 13th.
In the Daini control room,
operators are girding
for what seems inevitable:
venting radioactive steam
into the environment.
Then the cables and the motors
finally start falling
into place, and the mood shifts
dramatically.
MASUDA (translated):
When we got word
that they were finished running
the cables, there was applause.
Then they tested the motors
and reported,
"The motors are working!"
and there was more applause.
When the pumps were
finally working
for units one, two, and four,
there were three more bursts
of applause, one for each.
(translated):
It was such a rush!
I can't believe they did it.
What a team they are.
They pulled off
something incredible.
I thought, "They did it!"
(translated):
The pressure in Unit 1 had risen
to just under the containment
vessel's pressure limit.
We had about two hours to spare.
I'd say we made it
by the skin of our teeth.
NARRATOR:
At Daiichi, Superintendent
Yoshida has now lifted
the evacuation order,
and workers that had fled
start to return.
INAGAKI (translated):
Things had bottomed out
and for the first time we were
able to catch our breath.
Then we started to worry
about cooling the fuel pools.
NARRATOR:
Those pools are located
above the reactors
and are used to store both
spent and new uranium fuel.
There are more than 1,800
uranium fuel rods
in the pools
for units one through four.
They are not inside
the containment vessels,
and there is no backup system
to keep them filled with water.
Should the pools go dry,
the rods could overheat
and potentially catch fire
in the open air, releasing
a huge amount of radiation.
This is the worst-case scenario
that has haunted
Prime Minister Kan.
It could force him to order
a mandatory evacuation
of everyone for 150 miles
or more.
Tokyo uninhabitable...
maybe for decades.
It is hard to fathom.
Nuclear plant operator Chuck
Casto, then an NRC executive,
arrives at Fukushima Daiichi
in the midst of this turmoil
and uncertainty.
The biggest challenge
right away,
as soon as I stepped foot
on the ground, was,
"Should people take lethal doses
to stop this accident?"
The situation was desperate...
Concerns we had never faced
before...
And we were trying to work
our way through them
the best we could.
NARRATOR:
It is time for
desperate measures.
On the morning of March 17,
Self Defense Forces helicopters
fly four daring missions,
hoping to dump seawater
onto the Unit 3 spent fuel pool,
which appears
to be boiling away.
Radiation forces them to fly
high above the plant-- too high.
(translated):
In reality, barely any of
the water got into the pool.
And tensions were
still running high.
NARRATOR:
So they turn
to an elite rescue squad
from the Tokyo fire department.
NARRATOR:
They plan to use equipment
designed to fight
high-rise fires.
They arrive at the plant
late the next night.
NARRATOR:
They are led by Deputy Chief
Yukio Takayama,
a 35-year veteran.
TAKAYAMA (translated):
The plan was to get water into
Unit 3 by any means necessary.
It needed to be dead on,
not like when you put out a fire
and spray the water
anywhere you want.
TAKAYAMA:
Two thoughts kept running
through my mind:
"Please be over soon"
and "What will I do
if this place explodes?"
TAKAYAMA (translated):
I had never felt
that kind of fear before.
I thought, "This is
what it feels like
to really be in trouble."
NARRATOR:
They get the job done
in 20 minutes.
Day breaks.
The water is now flowing.
The fuel in storage is never
exposed to the air
and the feared radiation is
not released.
Tokyo is saved.
(translated):
Little by little,
in a small way, we started
to have some hope.
Up until then,
we were spiraling further down
and now we were dangling there.
We weren't falling anymore.
NARRATOR:
For the first time in days,
Takeyuki Inagaki finds the time,
and a working phone,
to call home.
(speaking Japanese)
(translated):
My wife asked me, are you okay?
I could tell she was very
emotional from her voice.
I said, "I'm alive for now
and I have all my limbs.
Please take care."
NARRATOR:
In the days and weeks ahead,
the nightmare does not end,
but at least it gets no worse.
Concrete pump trucks unleash
steady torrents of seawater
onto the fuel pools.
Power is fully restored to the
plant, finally, on March 21.
By June, they install a complex
filtration system
to remove cesium
from the water washing
through the radioactive debris
and flowing into the Pacific.
And slowly the answers start
trickling in.
Why did Unit 4 explode?
It used the same vent stack
as Unit 3.
When hydrogen built up there,
it seeped into Unit 4
via a shared duct.
Why didn't Unit 2 blow up
as they feared?
They realize the explosion at
Unit 1 knocked out a door
near the top of the Unit 2
reactor building.
It allowed hydrogen
and radiation to escape Unit 2.
While it was venting, the wind
shifted toward land,
sending the highest
concentrations of cesium
to the northwest.
The fallout will linger
for decades.
Eight months after
the earthquake and tsunami,
reporters tour
Fukushima Daiichi.
Superintendent Masao Yoshida
tries to downplay the worry.
(translated):
The plant is stable enough
for local residents to have
peace of mind.
However, it's still very
difficult to work
under the current conditions.
NARRATOR:
Yoshida had been reprimanded
by his TEPCO superiors
for disobeying orders
and injecting seawater
during the worst of the crisis.
What about his workers?
Six that ventured
into the reactor buildings
trying to open the vent valves
got the worst doses--
as much as 678 millisieverts
of radiation.
5,000 millisieverts is
considered lethal,
and 250 is the maximum
normally allowed
for nuclear plant workers
in an emergency.
The cancer risk
for those six Daiichi workers
is undoubtedly greater
in the long run.
But during that fateful week,
they all believed there was
no long run for them.
(translated):
To be blunt, there were
a number of times
that I thought I would
probably die.
We couldn't predict anything.
The worst-case scenario
for the meltdown
was that it would get
out of control.
I felt that was possible.
And so I thought,
"Maybe this is the end."
NARRATOR:
One month later,
the hot melted cores
finally drop
below the boiling point
of water.
Cold shutdown.
By then, Yoshida is gone.
He has cancer,
unrelated to his job.
He dies in July of 2013.
Yeah, he was always
keeping his head.
Always encouraging people.
(translated):
He was a good leader.
You might even say
he was superhuman.
Not just because of the quality
of his decisions,
but how quickly he made them.
Without him,
I could not have...
Yeah, I could not be here.
NARRATOR:
Fukushima, four years later.
What was once one of the largest
nuclear power plants
in the world
is now the center of the most
complex, expensive,
expansive cleanup
ever attempted.
It could take
as long as 40 years.
It will rely on technology
not yet invented
and the determination
of people not yet born.
The man in charge of it all is
the hero of Fukushima Daini.
Naohiro Masuda is now TEPCO's
chief decommissioning officer.
It is a very different challenge
than what he faced
in March 2011.
(translated):
This is the first time
anyone has attempted this kind
of decommissioning.
No one in the world
has this experience.
So when we try to set a goal
to work towards,
I can't even give
clear instructions
because we're still figuring out
what it is we're trying to do.
NARRATOR:
This is not Chernobyl,
hastily abandoned,
encased in a tomb
and encircled by a fence.
This is Japan,
where land is precious
and they have a history
of rising from ruin.
Here, they hope to erase
the painful past
and maybe one day
return to their homes.
OPERATOR (translated):
I was born and raised
in this area,
the same area where we are
decommissioning.
It's not possible
to live here now,
but we all have a strong desire
to make it habitable again.
I think that's
what keeps us working.
NARRATOR:
It is a disaster with deep roots
at high levels,
bad design decisions,
technological hubris,
a broken safety culture.
But in Japan,
the sins of the company
are the sins of its workers,
so they are considered culprits
as well as victims.
YUTAKA (translated):
What needed to be done was done.
I strongly regret
the inexcusable situation
that unfolded.
CASTO:
Mankind has never faced
the forces of physics
and the forces of nature
that those people faced.
The system may have failed,
but those operators did the best
they could with what they had.
In my mind,
they were absolute heroes.
INAGAKI (translated):
There's nothing to be proud of.
Most of the plant workers were
born and raised here.
They wanted to protect
their hometown,
protect their families.
The reality is,
tens of thousands of people are
still under evacuation...
and we're the ones
that caused that.
By no means are we heroes.
A This NOVA programed
is available on DVD.
NOVA is also available
for download on iTunes.
Japan's most powerful
earthquake ever...
(screaming)
...triggers a monster tsunami.
NARRATOR:
Fear washes over the nation.
NARRATOR:
But that's just the beginning.
Ten nuclear reactors
at two power plants
are crippled,
threatening the unimaginable.
(translated):
If Tokyo needed
to be evacuated,
I feared the entire nation
of Japan
would be paralyzed by chaos.
(translated):
It became darker and darker.
A terrifying situation.
We were fighting
an invisible enemy,
out-of-control reactors.
NARRATOR:
What will it take
to save the country
from lethal radiation?
CHUCK CASTO:
Mankind has never faced
the forces of physics
and the forces of nature
those people faced.
NARRATOR:
"Nuclear Meltdown Disaster,"
right now on NOVA.
Major funding for NOVA is
provided by the following...
We love science.
Supporting NOVA and promoting
public understanding of science.
And the Corporation
for Public Broadcasting.
And by PBS viewers like you.
Thank you.
And Millicent Bell,
through the Millicent
and Eugene Bell Foundation.
Additional funding from the
Montgomery Family Foundation.
NARRATOR:
This is the road to nowhere,
a once-thriving place
in one of the most prosperous
countries on Earth...
Japan.
Radioactive Japan.
Time stood still here
on March 11, 2011.
Houses that aren't homes.
Schools that are silent.
Stores shuttered.
Towns without people.
Past the checkpoints,
the scans,
and the meticulous suit-up,
layer upon layer upon layer
of protection
is the place we simply know
as Fukushima...
...site of three
nuclear reactor meltdowns.
(translated):
This is called the Central
Control Room.
All of the equipment
at the power plant
is operated from here.
NARRATOR:
He is a nuclear plant operator.
This is where
he has always worked.
He used to live nearby,
but now he too cannot go home.
He and his co-workers
are ashamed,
scorned by the neighbors
they once had.
OPERATOR (translated):
We've been through so much
in this control room.
It's hard to put into words.
NARRATOR:
He was here when it happened.
Now he is hoping to make amends
by helping clean up
the toxic mess.
OPERATOR (translated):
Four years ago,
this room was completely dark.
We had only small fluorescent
lights and flashlights.
We had given up
on our own survival.
Now, talking to you
with the lights on,
it seems like a lifetime ago.
NARRATOR:
This is the story
of the Fukushima meltdowns.
The infamous events at Fukushima
Daiichi, or number one...
(alarm blaring)
...told by those who were there
and risked everything.
NARRATOR:
And the lesser-known story
of its sister plant
seven miles away:
Fukushima Daini, or number two.
It faced the same onslaught
and challenges,
but thanks to a little luck
and a herculean effort,
it was saved
from ending up like this.
March 11, a bad day for Japan
and the world,
could have been so much worse.
NARRATOR:
The inevitable came
without warning at 2:46 p.m.
Two giant pieces
of the earth's crust,
tectonic plates,
move suddenly and violently.
One pushes down,
causing the plate above it
to spring upward like a catapult
along a 300 mile fault line .
In a nation all too familiar
with earthquakes,
it is the largest ever recorded:
magnitude nine.
Propagating outward
at 9,000 miles an hour,
record-breaking seismic waves
careen toward land
and the ten nuclear reactors
at the two Fukushima plant
all of them designed
by General Electric,
owned and operated by
the largest utility in Japan--
the Tokyo Electric
Power Company--
TEPCO.
They are there to feed
the insatiable energy needs
of Tokyo.
(translated):
Suddenly, I heard
the earth rumble,
like a fierce growl.
It was an extremely
intense earthquake.
But it wasn't only strong,
it was also terribly long.
NARRATOR:
An American nuclear reactor
service technician,
Carl Pillitteri, is there
doing some upgrades.
It was just one big hammer.
(screaming)
The entire building was moving.
Everything was coming down.
The lights were crashing
everywhere.
And it just got worse
from there, actually.
In one nanosecond, just
the entire floor went black.
OPERATOR (translated):
The shaking was like nothing
I had experienced.
The operators either held
onto that bar or crouched down.
That's how we endured
the earthquake.
INAGAKI (translated):
I just wondered,
"How long is this going
to continue?"
NARRATOR:
It lasted six minutes.
Takeyuki Inagaki
is general manager
of the maintenance department
for Units 1 through 4
at Daiichi.
He reports directly to the
superintendent, Masao Yoshida.
Both men have spent
their entire careers at TEPCO.
Inagaki worries about his wife
and two sons.
(translated):
When the earthquake hit,
I think I sent one email
to my wife explaining that
I didn't think I'd be able
to come home for some time.
After sending that email,
we became unable
to contact the outside.
We couldn't even make calls.
(clicking)
NARRATOR:
Seismometers at nuclear plants
are designed to trigger
an automatic emergency response
after an earthquake.
(shouting)
NARRATOR:
Power plant operators
routinely drill for this,
but it is still a risky,
tense event.
Called a SCRAM, it is designed
to put the brakes
on the nuclear chain reaction
of sustained fission.
A nuclear reactor
is fueled by uranium,
an element that naturally
splits apart,
releasing neutrons.
But uranium fission
can induce more fission.
When a loose neutron fires
into a nearby uranium nucleus,
it becomes unstable
and quickly splits.
Each time an atom splits,
it generates heat.
To make fission robust enough
to generate power,
uranium is enriched,
shaped into pellets,
and then stacked in long tubes
called fuel rods.
This ensures
lots of uranium atoms
are close enough to each other
to allow
a healthy chain reaction.
To manage the rate
of the reaction,
control rods
that absorb neutrons
are moved in and out of spaces
among the fuel.
During a SCRAM, the control rods
are pushed all the way in,
terminating the chain reaction.
By 3:02, operators at Daiichi
confirm the three reactors
that were online
have successfully SCRAM-ed.
And at Fukushima Daini,
all four reactors
running full throttle
also automatically shut down
safely.
Even though
the nuclear chain reaction
has now abruptly stopped,
the uranium fuel rods
remain very hot.
It's called decay heat.
DAVE LOCHBAUM:
The nuclear chain reaction
was stopped within seconds,
but the decay heat
continued to be a problem.
It takes approximately
20 to 24 hours
for the systems
to cool the reactor down
to less than 212 degrees
and achieve what's called
"cold shutdown."
NARRATOR:
At its core,
a nuclear power plant
is not unlike a pressure cooker
on a stove.
Water is heated
to the boiling point,
creating steam.
And steam under pressure
turns turbines,
generating electricity.
The complexity and cost
of nuclear energy
is about keeping the radioactive
genie in the bottle.
So the uranium fuel
sits inside rods underwater
in a steel pressure vessel
surrounded by a concrete
and steel containment structure
inside a reactor building.
All those layers of protection
are there
in case the water stops flowing.
If that happens,
it quickly boils away,
exposing the fuel,
and it melts,
turning into radioactive magma.
Unchecked, it will melt right
through the steel reactor vessel
and on to the concrete
and steel containment structure
that surrounds it.
So at the Fukushima plants now,
it is critical
that the electric water pumps
and valves keep running
for the reactor core
to safely cool down.
Power normally comes
from the electric grid,
and the earthquake
has caused a blackout.
But there is a plan B.
(whirring)
The plant is equipped
with diesel electric generators
to provide power
in an emergency.
They start automatically,
as they're designed to do.
LOCHBAUM:
If it had only been
the earthquake,
we wouldn't be here today.
The safety systems
were doing their thing,
the reactor cores
were being cooled,
and things were going
pretty well.
NARRATOR:
When the sea floor
suddenly moves upward
during the earthquake,
it causes the water
near the epicenter
to rise with it.
The giant swell is the start
of a tsunami.
(alarm blaring)
Forecasters issue
a tsunami warning.
They predict ten-foot-high waves
in Fukushima Prefecture.
The main buildings
at Daiichi and Daini
are about 30 feet
above sea level,
so no one worries much
about a tsunami.
NARRATOR:
And then, at 3:27 p.m...
the first of seven
giant waves
crashes over the seawall.
PILLITTERI:
Then I saw the tsunami coming.
I was on top of that hill,
and I wondered
if I was high enough.
This thing was, you know...
It was huge.
NARRATOR:
The tallest surge of water
is nearly 50 feet high,
nearly three times higher
than the seawall.
OPERATOR (translated):
I assumed there would be
a tsunami,
but not one 50 or 55 feet high.
I couldn't even imagine
a tsunami like that.
NARRATOR:
Fukushima Daiichi is inundated.
Two workers drown,
trapped in the basement
of the number four
turbine building.
Six generators,
along with the wiring,
switches, and breakers
connecting them to the plant
are located in the basements
of the turbine buildings
for Units 1 through 4.
The flood waters
destroy them all.
Two additional generators
behind Unit 4 are high and dry,
but their switching gear
is in the basement,
ruined by the seawater.
The generators would be useless.
Meanwhile, seven miles
to the south
at the other Fukushima plant--
Daini, or number two--
the crisis is equally dire.
The big waves roll in,
swamping key motors, wiring,
pumps, and generators.
NAOHIRO MASUDA (translated):
Immediately
after the tsunami hit,
this room lost power.
That's when I realized something
very serious had happened.
NARRATOR:
Naohiro Masuda
is the plant superintendent
on that fateful day.
He began his career here
at Daini,
reporting for duty in 1982
while it was still being built.
He knows it as well as anyone.
MASUDA:
This building is 40 feet
above sea level,
and if there was
a power outage here,
I imagined most of the buildings
near the sea
were damaged by the tsunami.
From that point on,
we knew we were in trouble.
NARRATOR:
Operators in the control rooms
give Masuda very bad news:
Units 1, 2, and 4
no longer have any operative
cooling systems.
(translated):
In nuclear power, we say,
"Stop, cool, and contain."
These are the three
most important functions.
When I realized that
we had lost cooling,
I knew the situation
was extremely serious.
NARRATOR:
But what needs to be fixed?
And how?
He orders a team
of about 40 workers
to go out
and inspect the damage.
(translated):
There were several hundred
aftershocks that day.
I really hesitated
to give the order
to send people out on-site.
NARRATOR:
They arrive in the rooms
housing electric motors
that run the pumps
that draw seawater
to cool the reactors.
(translated):
Cars had been washed
right up to the door,
and there were huge piles
of debris.
"How could you have sent us
to such a place?" they said.
NARRATOR:
Today, they have preserved some
of the evidence of the flood
that wiped out the motors
and their wiring.
MASUDA (translated):
Electrical supply systems
are located in this room.
The tsunami came up to here.
NARRATOR:
Back at Daiichi,
Reactors 1 through 4
are now in total darkness,
and things are quickly spiraling
out of control.
OPERATOR (translated):
We were in the middle
of dealing with the accident.
Then, all at once,
the lamps went out.
All sorts of alarms
were going off.
All of those went out.
Basically, a station blackout.
NARRATOR:
"Station blackout"--
the two most dreaded words
in the world
of nuclear power generation.
At Fukushima Daiichi,
Reactors 1 and 2 not only lose
the alternating current
that powers the pumps
and valves,
but also the direct current
that keep the instruments
working.
(translated):
It became darker and darker,
a terrifying situation.
And the operators weren't sure
what was happening.
We couldn't even tell
if there was water
in the nuclear reactors.
(translated):
We were at the starting line
of a race,
but we didn't know
if we'd need to run 100 yards
or if we'd need to run
a marathon.
NARRATOR:
The oldest reactor at the site
is Unit 1.
It began operation in 1971
and is equipped with outmoded
last-resort cooling systems
called isolation condensers.
LOCHBAUM:
The steam being produced
by the hot reactor core
was routed
into this large tank of water.
The water would cool the steam,
convert it back into water,
and it would drain back
into the reactor core
to be recycled
over and over again.
NARRATOR:
It is a passive system designed
to work on natural circulation
without any electrical power
at all.
So, is it working?
In the darkened control room,
they don't have a clue.
What they did not know
at the time
is valves
for the isolation condensers
are designed to automatically
close during a power failure,
stopping the flow
of steam and water.
When the isolation condensers
failed on Unit 1,
the reactor water level
just started boiling away
because it was no longer
being cooled and maintained
by the isolation condensers.
NARRATOR:
If the isolation condensers
are working properly,
vents on the side
of the reactor building
would be releasing
huge amounts of steam.
CHUCK CASTO:
There was steam coming out
of the discharge of it,
but they didn't realize
it wasn't sufficient.
So they thought they had
more time than they did.
NARRATOR:
Now, there is nothing
to stop the meltdown.
At 3:42 p.m., 15 minutes after
the tsunami waves rolled in,
TEPCO notifies the national
and local governments
that there is a "special event"
at the plant.
Actually, it is an emergency
that has never been envisioned.
FUKURA (translated):
It was a situation
that hadn't been anticipated.
We couldn't use
the procedure manuals.
OPERATOR (translated):
What was happening
was beyond what we trained for
on a daily basis.
Using what little information
we had,
we had to decide immediately,
"What can we do?
What should we do?"
It was a race against time.
NARRATOR:
They desperately need power,
but from where?
TEPCO dispatches
generator trucks,
but they are slowed by
earthquake and tsunami wreckage.
When they finally arrive
late on the 11th,
damage to the plant's
electrical system
makes it all but impossible
to connect them.
So they must improvise,
hoping to jury rig their
dead instruments back to life
by raiding the parking lots,
grabbing as many batteries
as they can from buses and cars.
INAGAKI (translated):
It took several hours
to figure out
how to connect the batteries.
They had the schematic
wiring diagram,
and they were furiously
examining it for several hours.
We ended up wasting
a lot of time.
NARRATOR:
Meanwhile, the water is
boiling away fast in Unit 1.
But how fast?
Six hours after the tsunami,
at 9:19 p.m.,
they finally get the batteries
and some portable
generators rigged
so the instruments
can flicker on.
The gauges show the water level
in Reactor 1,
normally 20 feet above the top
of the uranium fuel,
is now only eight inches
above it.
They pencil in a running record
of the water levels
right beside the gauge.
But the pressure in the vessel
is so high
it causes inaccurate
instrument readings.
They learn later
the uranium fuel
had actually been exposed
for three hours.
LOCHBAUM:
It's becoming more like
a lava flow from a volcano.
So it overheated, melted,
released radioactive contents,
and started falling into the
bottom of the reactor vessel.
NARRATOR:
In Tokyo, Japan's
prime minister, Naoto Kan,
worries that he might have
to order a mass evacuation
from Fukushima
all the way to Tokyo:
50 million people.
(translated):
If Tokyo had to be evacuated,
I feared
the entire nation of Japan
would be paralyzed by chaos
for quite a long time.
NARRATOR:
At 9:23 p.m., he orders everyone
living within two miles of
Daiichi to evacuate immediately
so TEPCO can prepare
to vent some steam--
radioactive steam.
At this stage,
radioactive iodine-131
is the isotope
of greatest concern.
It is linked to thyroid cancer.
Children are most vulnerable.
INAGAKI (translated):
We knew we had to vent,
but the question was, "How?"
There was no electricity,
and the valve was pneumatic.
We needed compressed air
from a compressor to open it,
but we didn't even have that.
NARRATOR:
Kan becomes increasingly
frustrated and impatient.
KAN (translated):
Even though we approved it,
many hours went by
and there was still no venting.
We asked them why.
A specialist from TEPCO told me,
"I don't know the reason."
Much of the information
he was getting
from his government
and the utility
turned out not to be true,
and he had no source
of independent knowledge
of what was going on
in those reactors.
NARRATOR:
Kan decides the only way
to know for sure is to go there,
and so early on the morning
of March 12,
he flies to Fukushima Daiichi.
He passes over mile upon mile
of utter devastation
from the earthquake and tsunami.
Nearly 16,000 are dead.
He lands at Daiichi
just after 7:00,
about 15 hours
after the tsunami.
KAN (translated):
I met with Superintendent
Yoshida for 45 minutes.
While he explained
the situation on-site,
I could see that he was a person
who could be trusted.
NARRATOR:
The prime minister endorses
the superintendent and his plan.
Yoshida vows to begin venting
at 9:00 a.m.
But there is much to do
and much to consider.
INAGAKI (translated):
To go into a pitch-black
reactor building
with high pressure levels,
I don't know if I should say it,
but it felt like we were putting
together a suicide squad.
NARRATOR:
To open the vent, they need
to manually turn two valves:
one in the basement
and another on the second floor.
At 9:04 a.m., a pair of workers
makes their way
through a dark labyrinth
to the second floor
of the Reactor 1 building.
It takes them 11 minutes
to open the valve.
Nine minutes later
a second team heads
for the valve in the basement.
They get to a point about midway
and the radiation is higher
than they thought they'd get.
They basically had drawn up,
"If radiation gets to this
point, we'll go back."
Well, they got to that point
before they got to the valves.
NARRATOR:
They abort their mission.
In the Emergency Response
Center, they realize
they must find a way to open
the vent remotely.
They scramble to find an air
compressor that can be attached
to the pipe that blasts
the valve open.
Finally, at 2:50 p.m.,
steam starts rising
from the exhaust tower
and the pressure starts
dropping.
Could the worst be over?
Actually, it is just
about to begin.
At Daini, where the power
is still out
and the reactors
are getting hotter,
there is a stroke of luck.
There is power inside the
radiation waste building
behind Reactor 1.
But they need it down
by the water.
Naohiro Masuda decides
to lay cables,
hoping to restore cooling
to the reactors.
Each of the four reactors needs
three operative pump motors.
They need to lay five-and-a-half
miles of cable
to connect them all.
He needs supplies urgently--
at least 50 big spools
of heavy-duty cable.
Masuda orders the cable,
but the shipment is delayed.
(translated): The police were
busy redirecting traffic
for evacuations
and when the truck hit those
detours it wound up going
in the completely wrong
direction.
NARRATOR:
While they wait at Daini,
the crisis is getting
much worse at Daiichi.
Uranium fuel rods are encased
in zirconium.
LOCHBAUM:
If it gets too warm,
there's a chemical reaction
between the zirconium
and the water or steam
to produce large amounts
of hydrogen.
NARRATOR:
A containment structure
on a boiling water reactor
is sealed with a dome-shaped top
that is removed for refueling.
The pressure in Reactor 1
is now so high
that it slightly lifts the top.
The hydrogen escapes
through the gap
and into the reactor building,
where it mixes with air.
It would be just a matter of
time before a spark would ignite
the highly flammable gas.
It is 3:36 p.m.
OPERATOR (translated):
Suddenly there was an upward
thrust, an impact that seemed
to push the whole building
upward
and it became completely dark.
(translated): I thought it was
just another aftershock,
but we all sensed something
was very wrong.
(translated): Then I was told
by headquarters
that the top of the reactor
building
was completely destroyed.
When I heard that,
I was shocked.
NARRATOR:
It is a devastating setback.
INAGAKI (translated):
I think that most of us
working at the time
didn't feel like we were going
to make it out alive.
NARRATOR:
At Daini, workers are preparing
to lay the heavy cables
when they get word
of the explosion at Daiichi.
MASUDA (translated):
After the explosion, I had
everyone outside come back
into the Emergency
Response Room.
There were 500 to 600 people
in the room.
I said, "Please trust me.
"I definitely won't do anything
to harm you,
"but Fukushima Daini is still
in trouble
and I need you to do your best."
NARRATOR:
The cables arrive
on the morning of the 13th.
Finally, the heavy lifting
to save Fukushima Daini begins.
(translated): These were
large-capacity motors,
several hundred amperes,
so the cables were fairly thick.
Each person had to walk
while carrying around
35 pounds of cable.
NARRATOR:
It is a race against time
and physics.
(translated): Normally, If you
wanted to lay that much cable,
it would take you about a month.
I didn't actually think
it was possible
in the amount of time
that we had.
YUTAKA (translated):
A total of around 200 workers
were involved.
We swapped people out
when they got exhausted.
NARRATOR:
In the midst of this, Masuda is
running out of fresh water
to cool his crippled reactors.
He asks TEPCO headquarters
for a shipment.
MASUDA (translated):
I asked Tokyo for 4,000
tons of water,
but instead they delivered
4,000 liters
of bottled drinking water.
That made me realize that we
were on our own.
We couldn't count on Tokyo.
So we started looking for water.
NARRATOR:
He remembers a creek
used as a water supply
during construction
of the plant.
Workers repair
the leaky old pipe
with a scavenged bicycle tube.
At Daiichi, events are still
overtaking them.
As the dust settles at Unit 1,
they learn five workers
are injured.
With freshwater reservoirs
exhausted,
they scramble to inject seawater
into the reactors.
By 7:04 p.m., success.
But using corrosive seawater
means the reactors will surely
be destroyed.
TEPCO headquarters tells
Superintendent Yoshida to stop
while they seek
government approval.
LOCHBAUM:
So Yoshida does
this very dramatic thing
where on the video conference,
he orders the people
to stop the seawater injection.
Before that, he called them over
and said,
"I'm going to order you to stop
the seawater injection.
"Ignore that.
"That's just for Tokyo.
You continue seawater
injection."
(translated):
Personally, I think the decision
that Yoshida made
was the right one.
(translated): If we had stopped
the seawater injection
at that point, things would
have been much worse.
(translated): In the meantime,
Unit 3 was becoming unstable.
Now our mission was "Don't let
Unit 3 turn into Unit 1."
NARRATOR:
With no battery power,
they are unable to open the
valves to begin venting Unit 3.
And there are no handles
on these valves.
So they grab car batteries,
hoping to open them
from the control room.
By 9:00 a.m. Sunday, March 13,
the Unit 3 reactor core
is exposed and melting.
The pressure keeps rising.
Fearing another hydrogen
explosion,
Yoshida orders workers
to retreat
to the Emergency Response Center
early on the morning
of March 14.
But the pressure plateaus and he
lifts the order an hour later.
INAGAKI (translated):
We alternated between deploying
and pulling back workers
because we were afraid of
another hydrogen explosion.
Unfortunately, we had close
to 50 people positioned
around Unit 3
when the explosion happened.
NARRATOR:
It is 11:01, March 14.
INAGAKI (translated):
Since there were so many people
out there,
I was really afraid
for their safety.
"It's very possible someone was
killed," I thought to myself.
Then, one by one,
people started to trickle back.
They were all very pale in the
face and some were bleeding.
NARRATOR:
When Unit 3 explodes,
11 workers are injured.
Amazingly, no one is killed.
And when we finally accounted
for everyone,
that's when we noticed the water
level in Unit 2 was dropping.
NARRATOR:
It seems inevitable that Unit 2
will be the next to blow.
At noon on March 14, an hour
after the explosion at Unit 3,
the water covering
the hot radioactive fuel
begins to drop precipitously.
An hour and a half later,
the emergency backup
cooling system fails.
Superintendent Yoshida quietly
tells a few trusted workers
to prepare buses
for an evacuation,
but for now he has no choice
but to order his men
back into harm's way.
INAGAKI:
After the explosion of Unit 3,
he begged us to again go
to the field to save Unit 2.
It was very impressive.
NARRATOR:
But by 6:22 p.m.,
the water is gone.
The uranium fuel is completely
uncovered and melting.
Again they try to use car
batteries to open the vents
and relieve some pressure.
No luck.
(translated): From the 14th
until early in the morning
on the 15th,
it was really...
how can I describe it?
It was like being in hell.
NARRATOR:
As day breaks on the morning
of March 15,
they hear a loud explosion.
(explosion)
But it is not what they dread.
It is a complete surprise.
There has been
an explosion in Unit 4.
But this reactor was shut down
for maintenance
when the tsunami hit.
What could have happened there?
And what saved Unit 2
from blowing up?
The investigation
will have to wait.
Superintendent Yoshida orders
an immediate evacuation
of 650 workers.
He and nearly 70 supervisors
would stay.
In the confusion, they become
known as the "Fukushima 50."
(translated):
We were fighting an invisible
enemy, out-of-control reactors.
From that perspective,
it was like fighting a war.
NARRATOR:
It is midnight on the 13th.
In the Daini control room,
operators are girding
for what seems inevitable:
venting radioactive steam
into the environment.
Then the cables and the motors
finally start falling
into place, and the mood shifts
dramatically.
MASUDA (translated):
When we got word
that they were finished running
the cables, there was applause.
Then they tested the motors
and reported,
"The motors are working!"
and there was more applause.
When the pumps were
finally working
for units one, two, and four,
there were three more bursts
of applause, one for each.
(translated):
It was such a rush!
I can't believe they did it.
What a team they are.
They pulled off
something incredible.
I thought, "They did it!"
(translated):
The pressure in Unit 1 had risen
to just under the containment
vessel's pressure limit.
We had about two hours to spare.
I'd say we made it
by the skin of our teeth.
NARRATOR:
At Daiichi, Superintendent
Yoshida has now lifted
the evacuation order,
and workers that had fled
start to return.
INAGAKI (translated):
Things had bottomed out
and for the first time we were
able to catch our breath.
Then we started to worry
about cooling the fuel pools.
NARRATOR:
Those pools are located
above the reactors
and are used to store both
spent and new uranium fuel.
There are more than 1,800
uranium fuel rods
in the pools
for units one through four.
They are not inside
the containment vessels,
and there is no backup system
to keep them filled with water.
Should the pools go dry,
the rods could overheat
and potentially catch fire
in the open air, releasing
a huge amount of radiation.
This is the worst-case scenario
that has haunted
Prime Minister Kan.
It could force him to order
a mandatory evacuation
of everyone for 150 miles
or more.
Tokyo uninhabitable...
maybe for decades.
It is hard to fathom.
Nuclear plant operator Chuck
Casto, then an NRC executive,
arrives at Fukushima Daiichi
in the midst of this turmoil
and uncertainty.
The biggest challenge
right away,
as soon as I stepped foot
on the ground, was,
"Should people take lethal doses
to stop this accident?"
The situation was desperate...
Concerns we had never faced
before...
And we were trying to work
our way through them
the best we could.
NARRATOR:
It is time for
desperate measures.
On the morning of March 17,
Self Defense Forces helicopters
fly four daring missions,
hoping to dump seawater
onto the Unit 3 spent fuel pool,
which appears
to be boiling away.
Radiation forces them to fly
high above the plant-- too high.
(translated):
In reality, barely any of
the water got into the pool.
And tensions were
still running high.
NARRATOR:
So they turn
to an elite rescue squad
from the Tokyo fire department.
NARRATOR:
They plan to use equipment
designed to fight
high-rise fires.
They arrive at the plant
late the next night.
NARRATOR:
They are led by Deputy Chief
Yukio Takayama,
a 35-year veteran.
TAKAYAMA (translated):
The plan was to get water into
Unit 3 by any means necessary.
It needed to be dead on,
not like when you put out a fire
and spray the water
anywhere you want.
TAKAYAMA:
Two thoughts kept running
through my mind:
"Please be over soon"
and "What will I do
if this place explodes?"
TAKAYAMA (translated):
I had never felt
that kind of fear before.
I thought, "This is
what it feels like
to really be in trouble."
NARRATOR:
They get the job done
in 20 minutes.
Day breaks.
The water is now flowing.
The fuel in storage is never
exposed to the air
and the feared radiation is
not released.
Tokyo is saved.
(translated):
Little by little,
in a small way, we started
to have some hope.
Up until then,
we were spiraling further down
and now we were dangling there.
We weren't falling anymore.
NARRATOR:
For the first time in days,
Takeyuki Inagaki finds the time,
and a working phone,
to call home.
(speaking Japanese)
(translated):
My wife asked me, are you okay?
I could tell she was very
emotional from her voice.
I said, "I'm alive for now
and I have all my limbs.
Please take care."
NARRATOR:
In the days and weeks ahead,
the nightmare does not end,
but at least it gets no worse.
Concrete pump trucks unleash
steady torrents of seawater
onto the fuel pools.
Power is fully restored to the
plant, finally, on March 21.
By June, they install a complex
filtration system
to remove cesium
from the water washing
through the radioactive debris
and flowing into the Pacific.
And slowly the answers start
trickling in.
Why did Unit 4 explode?
It used the same vent stack
as Unit 3.
When hydrogen built up there,
it seeped into Unit 4
via a shared duct.
Why didn't Unit 2 blow up
as they feared?
They realize the explosion at
Unit 1 knocked out a door
near the top of the Unit 2
reactor building.
It allowed hydrogen
and radiation to escape Unit 2.
While it was venting, the wind
shifted toward land,
sending the highest
concentrations of cesium
to the northwest.
The fallout will linger
for decades.
Eight months after
the earthquake and tsunami,
reporters tour
Fukushima Daiichi.
Superintendent Masao Yoshida
tries to downplay the worry.
(translated):
The plant is stable enough
for local residents to have
peace of mind.
However, it's still very
difficult to work
under the current conditions.
NARRATOR:
Yoshida had been reprimanded
by his TEPCO superiors
for disobeying orders
and injecting seawater
during the worst of the crisis.
What about his workers?
Six that ventured
into the reactor buildings
trying to open the vent valves
got the worst doses--
as much as 678 millisieverts
of radiation.
5,000 millisieverts is
considered lethal,
and 250 is the maximum
normally allowed
for nuclear plant workers
in an emergency.
The cancer risk
for those six Daiichi workers
is undoubtedly greater
in the long run.
But during that fateful week,
they all believed there was
no long run for them.
(translated):
To be blunt, there were
a number of times
that I thought I would
probably die.
We couldn't predict anything.
The worst-case scenario
for the meltdown
was that it would get
out of control.
I felt that was possible.
And so I thought,
"Maybe this is the end."
NARRATOR:
One month later,
the hot melted cores
finally drop
below the boiling point
of water.
Cold shutdown.
By then, Yoshida is gone.
He has cancer,
unrelated to his job.
He dies in July of 2013.
Yeah, he was always
keeping his head.
Always encouraging people.
(translated):
He was a good leader.
You might even say
he was superhuman.
Not just because of the quality
of his decisions,
but how quickly he made them.
Without him,
I could not have...
Yeah, I could not be here.
NARRATOR:
Fukushima, four years later.
What was once one of the largest
nuclear power plants
in the world
is now the center of the most
complex, expensive,
expansive cleanup
ever attempted.
It could take
as long as 40 years.
It will rely on technology
not yet invented
and the determination
of people not yet born.
The man in charge of it all is
the hero of Fukushima Daini.
Naohiro Masuda is now TEPCO's
chief decommissioning officer.
It is a very different challenge
than what he faced
in March 2011.
(translated):
This is the first time
anyone has attempted this kind
of decommissioning.
No one in the world
has this experience.
So when we try to set a goal
to work towards,
I can't even give
clear instructions
because we're still figuring out
what it is we're trying to do.
NARRATOR:
This is not Chernobyl,
hastily abandoned,
encased in a tomb
and encircled by a fence.
This is Japan,
where land is precious
and they have a history
of rising from ruin.
Here, they hope to erase
the painful past
and maybe one day
return to their homes.
OPERATOR (translated):
I was born and raised
in this area,
the same area where we are
decommissioning.
It's not possible
to live here now,
but we all have a strong desire
to make it habitable again.
I think that's
what keeps us working.
NARRATOR:
It is a disaster with deep roots
at high levels,
bad design decisions,
technological hubris,
a broken safety culture.
But in Japan,
the sins of the company
are the sins of its workers,
so they are considered culprits
as well as victims.
YUTAKA (translated):
What needed to be done was done.
I strongly regret
the inexcusable situation
that unfolded.
CASTO:
Mankind has never faced
the forces of physics
and the forces of nature
that those people faced.
The system may have failed,
but those operators did the best
they could with what they had.
In my mind,
they were absolute heroes.
INAGAKI (translated):
There's nothing to be proud of.
Most of the plant workers were
born and raised here.
They wanted to protect
their hometown,
protect their families.
The reality is,
tens of thousands of people are
still under evacuation...
and we're the ones
that caused that.
By no means are we heroes.
A This NOVA programed
is available on DVD.
NOVA is also available
for download on iTunes.