Thread by @m_older

Later today I'm giving a talk on Fukushima Dai-Ichi as part of @UniLeiden's very cool semester-long study of a crisis, with different sector-area specialists invited to talk. I'm in mainly because of this report I co-wrote years ago for @suretenucleaire
irsn.fr/FR/expertise/r…

so as I prep here are a few details about the unfolding of the crisis you may not be familiar with

The operators, and the rest of the plant, did not know right away that a tsunami had hit. How would they know? They were in windowless rooms and communications were down or jammed because of the earthquake.

The earthquake happened at 14:46. The reactors scrammed correctly and were cooling according to plan. The large waves didn't hit until 15:35. Yes, there had been tsunami warnings, but the seawall was designed to repel tides of up to 5.7 meters, or almost NINETEEN FEET

It wasn't like they were used to looking over and seeing the ocean right there. In fact, later, when they were trying to get seawater INTO the reactors to cool them, it was challenging to get the water up from so far below.

It probably occurred to them that it might be a tsunami; but after an earthquake of that size the sudden loss of power that was the warning of further disaster could have been caused by any number of events.

(apparently the link I posted in the first tweet isn't working, you can get to the report from here instead: irsn.fr/EN/newsroom/Ne…)

The water did not directly damage the reactors. It damaged electricity panels, sea-water pumps for water-cooled emergency diesel generators, and the generators themselves and batteries. Meanwhile grid electricity had been cut off by the earthquake.

As I said, the reactors had scrammed and shut down correctly after the earthquake. They needed outside electricity to be cooled. It only took a few hours for the lack of cooling mechanisms to become disastrous.

Meanwhile, the operators were sitting in a dark room. Their control panel indicators didn't work. Their control panel controls didn't work. They couldn't see outside. They had a hard landline connection to the plant emergency operations center, which wasn't much better off.

Let's go back for a moment (this is why we prep). The reactors had scrammed correctly and were cooling correctly, but that process wasn't totally automatic. The operators were managing the cooling by turning the emergency cooling systems on and off.

There were different emergency cooling systems for reactors 1 and 2, which shared a control room (reactor 3, with a different control room, had the same system as 2). The operators had emergency operating procedures for these systems, but they had never used them before.

So they've just been through a 9.1 earthquake, which is not fun, and they're dealing with emergency systems to manage nuclear reactors very near the town where they and their families live, and suddenly all the lights go out and the controls are unusable.

Meanwhile, the rest of the plant staff has gone to the earthquake resistant emergency operations building. They also don't know what's going on, but the man in charge, Yoshida, knows this is bad and pretty much immediately requests electricity-generating vehicles.

Those set out within an hour or so. Normally it doesn't take very long to get from place to place in Japan, which has very good highways, but there were earthquake damages and on the coast massive tsunami debris blocking the roads.

The emergency operations room normally sees the same reactor indicators as the control room, so they were almost as shocked as the operators when those disappeared, and Yoshida told one of his teams to figure it out.

Meanwhile, the operators were doing their own improvising. They didn't know what had happened, but they knew conditions had changed, and they developed new safety procedures for anyone leaving the control room: pair up, permission, time-limit.

There was no cell service and the PA system didn't work, so if anyone left the room there would be no way to communicate or contact until they came back. That is so unusual for us these days, it's worth emphasizing how disturbing it is.

So the first thing was to determine whether the reactors were being cooled or not. The reactor 1 emergency cooling mechanism *theoretically* could run on a vapor condensation loop without electricity. But the valves needed to be in the right positions and it needed water.

the internal valves were totally inaccessible (as in, IN THE REACTOR) and could not be operated manually. Also they ran on AC, not DC.

A reporter who interviewed the operators for this honestly fucking amazing book (which I laboriously read in Japanese because it hadn't been translated yet) amazon.com/dp/B0833Y1WX9/… wrote that the mantra at this point was to inject water, somehow.

The reactors - the fuel rods - are kept cool by water, and if the water isn't circulating it will evaporate away from the extreme heat and then the rods will melt right through the containment

(experts out there, if I get anything wrong on the engineering please correct me, I learned all this but my focus was on the human/organizational side and this was a long time ago)

so they KNOW they have to get water in there, this is the only thing they can do, and they go through all sorts of efforts and bricolage to try to do it, but also? they really really want to know if it's already happening, even partially. They want to know how much time they have

They're used to knowing everything about the reactor through their instruments! And at that moment they no nothing. There are quotes about them comparing the feeling to being blind or without hands or feet after this connection to the machine is severed.

Wild. But how do you feel when your wifi goes down?

The wifi that is your connection to the world but also is used to spy on you, steal your data, and manipulate you with it?

ANYWAY. The indicator for water level illuminates briefly to show that the level is low, but not yet critical; but it's dropping as they watch, and then it flickers out, and they're left with that sensation of rapidly approaching doom and no information.

But these absolute heroes, instead of running screaming away- which in fairness would not have been a good strategy, and their homes and families were nearby too -figure they can maybe reroute the fire control sprinkler system to pump water into the core. But they need a pump so

the supervisor sends a team to the basement of the turbine building to check on the diesel-driven fire pump there. But to reach it they have to take an underground tunnel, and while they're going there's a tsunami alert, so they retreat, because the tunnel could be swamped.

They put an operator on the roof to watch the ocean and yell a warning if there is a wave coming & send another team. It's 17:19, almost 3h after the earthquake. Dead fish in the tunnel. Pump works, but they need to re-configure the line, so they put it on standby to save fuel.

By the way, if you're finding this interesting, my talk today is part of a closed university course, but @Kennedy_School @BelferCenter has a conference this week on nuclear safety. I'm in a roundtable on Friday but lots of other great events

https://twitter.com/BelferCenter/status/1364987056066342920?s=20

At around this time Yoshida at the emergency response center has thought of using fire engines to try to inject water, something that is not in the procedures but that he learned about during his experience in an earthquake at a different plant, so he requests those.

The operators send a team to the reactor building to look at a gauge there to figure out the water level in the tank for the emergency cooling system, but they stop at the door of the building because their dosimeters are going off and they're not wearing protective suits.

that is a BAD SIGN, but they really hope still that maybe the emergency cooling is working at least partially, and then some of the indicators come back on line (possibly batteries dry out). Nothing on those inaccessible internal valves, but the external valves show as closed so

they mash the (probably not working but who knows?) buttons to try to open the external valves. Then they stick their heads out of the back door to see if there's any steam coming out of the vent to indicate the cooling is working.

They see some steam; but then it dissipates. This is what happens when the incredibly complex systems we have built around us fail: we go back to sketchy, uncertain physical evidence.

The ERC, meanwhile, is hoping to get electricity back up to facilitate GETTING WATER INTO THE REACTOR. So people are going through the debris-strewn parking lot, scrounging batteries from cars, and trying to connect them in series to power the indicators in the control room.

bricolage, comemierdas.

by which I mean: all the sleekness, all the modernity, all the power and intimidation of our most scientific engineering achievements are on a knife-edge from deadly farce and desperate, cobbled-together reappropriative ingenuity.

ok I have to go actually give this lecture now, if there's enough interest I guess I might come back and do the rest later, or you could just read the report: irsn.fr/EN/newsroom/Ne…

Woohoo, 3-hour lecture done! I think it went well, but in MS Teams with no way of seeing people's faces ¯\_(ツ)_/¯
I have lots of other things to do but I hate leaving stories unfinished so I'll go on a bit, maybe sporadically as other things come up. Where were we...?

Right! So at this point it seems pretty clear that the IC emergency cooling for Reactor 1 isn't working, and the operators are trying to go ahead with the idea for connecting the emergency fire pump. They need to reconfigure the line to take the water to the core. Normally

that would mean flicking some switches in the control room, but without electricity they're going to have to go into the reactor building and move the valves by hand. First they had to figure out which valves, since this wasn't a normal thing, so they studied blueprints.

This was an operator-driven mission, not something that they were told to do (and definitely not in the procedures). They knew it would be dangerous; after all, they had no idea how close any of the reactors were to meltdown.

The shift leader offered to go, not wanting to send others, but they told him that consistent leadership in the control room was more important. Also, no one wanted the younger operators to go. Five senior ones were chosen.

They found the building strangely dark & quiet without electricity. Some of the valves were large and hard to turn, and they were hampered by their protective equipment. But they were able to reconfigure the line and got back around 20h/8pm. 50 minutes later the pump was started.

So the water was flowing! But pressure in the reactor was already too high for the water to get in. There was a valve they could use to release pressure into the suppression chamber (don't ask; another part of the reactor complex) but, again, they couldn't activate it remotely.

The ERC is trying to figure out solutions and, in part from experience of a smaller earthquake at a different plant, hit on the idea of using fire engines, connecting them to the reconfigured line and pumping water in from there. They started clearing debris from internal roads.

Around this time someone found a small generator, and they connected it in the control room for lighting, which was good. but what they really wanted was indicators to work & that was more difficult: apparently they sorted through 10k pages of diagrams to find the connections

(all citations and references are in the report, but most of this comes from the major reports, NAIIC, ICANPS, TEPCO reports, and the book by Kadota linked upthread)

So electricity, it turns out, is very complicated, and people who work at an electricity plant wouldn't be likely to know how to connect car batteries to an indicator panel. Similarly, getting electricity back up for the plant wasn't as simple as bringing in a line or a truck:

the plant had power systems w transformers to change voltage to 3 different levels as needed, & those power systems had been damaged by the tsunami. When they had finally cleared the debris and the electricity vehicles arrived, they had the wrong connections and couldn't be used.

Not only were the operators not running away: more and more off-duty operators were showing up and going into the control room. When shift change came the original operators didn't leave, and the same supervisor remained in charge.

MEANWHILE, natch, everyone outside the plant is flipping out, and they're mostly doing it in an uninformed way, because there's no solid information. The operators couldn't "see" the reactor through their indicators; that uncertainty rippled out to the plant, company, government.

At 20:50 Fukushima Prefecture gives an evacuation order even though they have no authority to do so, because they don't have enough information and they're worried. Half an hour later, the Prime Minister does the same (with a slightly larger radius).

They FINALLY manage to connect power to the water level indicator for Reactor 1: 200 ml above fuel level. Not good, but better than they had expected! Relief! Cooling might be working! They disconnect again to save the battery power. What they didn't know was [dun dun DUN]

that indicator was almost certainly already malfunctioning as a result of being in CLOSE PROXIMITY TO A NUCLEAR MELTDOWN. But the indicators were their normal connection to the plant; they trusted them. And, they wanted to believe.

When they reconnected the indicator 30 mins later, water level read even higher. It wasn't until almost 2 hours later, nearly midnight, that they learned the pressure in the containment building was already beyond operating specs. Something was very wrong.

Going to take a break at that ominous juncture, but another plug: if you're into tech and society, I'll be talking to @divyastweets about her fabulous new novel MACHINEHOOD and what it says about AI, Big Data, and ethics at @strandbookstore later tonight: strandbooks.com/events/event18…

Up until this point the general consensus had been that reactor 2 was worse off than reactor 1. Operators hadn't been able to reach the fire pump for reactor 2 at all; its room was flooded. The plant had basically told authorities they were pretty sure reactor 2 was in meltdown.

But around the same time that it became clear reactor 1 was in trouble, they were able to get some measurements for reactor 2 that suggested the cooling there was working. Focus shifted to reactor 1. With pressure building in the containment building & risk of explosion,

they would need to vent some of the radiation from the containment building into the air. This was a serious decision; reports mention frequently that it "had never been done in Japan before" (I 🙄 a little because, my dudes, you are only as good as your latest nuclear disaster)

(I use "dudes" there advisedly. very few women in this story). Venting means releasing radiation into the air, which is not something you want to do, but is better than an uncontrolled explosion, so they had little choice at this point.

It was also not easy to do with no electricity. As usual, what would have been a switch or two on a control panel now meant physically going to the building & turning valves. Fortunately, some of the work of figuring out valves had already been done in the interest of reactor 2

So just after midnight on March 12, some nine hours after the earthquake, Yoshida gave the order to prepare venting for reactor 1 -& for reactor 2, because he figured it would need it sooner or later. They weren't going to do it right away, however; they would wait for evacuation

of the surrounding areas. That meant the radiation levels would rise, but also gave the operators time to prepare. They were ordered to figure out teams, and again excluded young and refused supervisor. 3 teams of 2 were selected, 1 for each valve and 1 backup.

Apparently TEPCO was not legally required to inform govt about venting, but they did, which was good seeing as TEPCO could not order evacuations. The downside was then anxious politicians in Tokyo kept asking them when the venting was going to happen <foreshadowing>

MEANWHILE, I don't know if you remember that pump they were trying to use to get water into the core but it didn't have enough pressure? At almost 2am it stopped working. Operators spent an hour finding fuel, transporting it, and loading it in, but it wouldn't restart.

And it's just like - we've all had those moments with mechanical things that just won't work and we can't figure out why. but wow, in that moment, even though it wasn't even doing what they wanted it to do, that must have just felt devastating.

The ERC, tho, had already given up on the pump and was working on fire engines. They were 3 already on site.
Only 1 still worked.
No one at TEPCO, INCLUDING THE ON-SITE FIREFIGHTERS, was qualified to operate it.

And here we get to the labor dynamics section of the story, because you know who was qualified? sub-contractors. Did you know there were functions of nuclear power plant operations that are subcontracted?

(There's actually a French movie in which I think this is part of the plot, although I never got around to seeing it... oh yeah: en.wikipedia.org/wiki/Grand_Cen…)

They still have to figure out where to connect the fire engine hose on the outside of the building so the reconfigured pipes will get the water to the core. Remember, this is a made-up, cobbled together solution, not planned or prepped for. More blueprints!

so a team including TEPCO and subcontractor heads out to where the port should be, and the wall is covered with tsunami debris and they can't find the port. They went back to the ERC, looked at blueprints some more, and found a person who HAD BEEN TO THE PORT BEFORE and went back

and found the port.
One of the fascinating things to me in this story is all the layers of knowledge, from first-hand, to mediated by instruments and electricity, to pre-stocked in blueprints.

So they hook up the fire-engine to port, pump in its tank of water (in the meantime, the pressure in reactor has dropped some, probably because of radiation leaks). Success! But a fire-engine tank's worth of water is not much to a nuclear reactor in meltdown, so

they drive to 1 of damaged fire engines and transfer the water in its tank to this 1. But before they can inject that, the radiation levels climb and the head of the subcontractor doesn't want his team working in those dangerous conditions, which are not covered by the contract.

TEPCO requests their help, negotiates, and they agree to a TEPCO team running the fire engine with 1 person from the subcontractor to assist. They decide to use the firefighting cisterns, and drive back and forth but that's time-consuming, so they set up a line and by 5:46 am

the fire engines are set up to run continues injection (until the cisterns run out <foreshadowing>). The subcontractor rep keeps changing out to avoid too much exposure.

Because radiation levels at the plant are pretty high at this point. They are even high in the main control room, where some of the operators are crouching on the ground to try to lessen exposure. They're still preparing for venting and waiting for the go. Some are visualizing

the route. The ERC is helping ("helping"?) by calculating the time they should spend in the reactor building for "maximum" exposure: 17 minutes. Maximum is, of course, a subjective and variable value in this context. No one knows exactly how much is too much.

At 3am (nobody is sleeping; I mean, would you?) the politicians in Tokyo hold a press conference about the venting, which they think is about to happen. Meanwhile the ERC is calculating just how much radiation will be released, which they tell the govt around 3:45.

At around 4:45 the ERC delivers protective equipment to the control room. There is not a whole lot of protective equipment available for the number of people and length of the crisis.

Remember how I mentioned that politicians were getting impatient? So around dawn someone lets the station superintendent know he's about to get a visit from the Prime Minister.

The Prime Minister couldn't understand why the venting hadn't happened yet and why he couldn't get the information he wanted. Another theme: people being choked off from information they are used to having and reacting badly, or at least desperately (again, imagine no wifi).

So PM gets into a helicopter and flies out. (lol I just looked it up on Google Maps to check how far it is from Tokyo and "CLOSED". Ya think?)

it's about 250 kilometers. The PM shows up. They have to get him from his helicopter to the ERC, which means more protective equipment (keep in mind each set can only be used once, because radiation, and also they lost some in the tsunami).

PM demands to know why venting hasn't happened yet; the supervisor, Yoshida, manages to calm him down and tells him venting will happen at 9am. He leaves at 8. At 9:02 the ERC gets information that the evacuation is complete.

At 9:04 the 1st of the 3 operator teams leaves the control room.
At 9:15 they opened the valve.
At 9:24 they were back in the control room, and the 2nd team left.
At 9:30 the 2nd team returns. The radiation was too high.

Plan I-don't-even-know-what-letter-we're-on-at-this-point: forget the valve. They'll vent by opening a different valve, on the large suppression chamber, which I guess opens from an outside wall? and is a compressed air valve.

That means they needed an air compressor to open it! Which they didn't have. So they asked around the sub-contractors! And found one, and the adapter. They also got a small generator.

In the meantime they were pushing the button for the valve anyway, just in case there was some leftover air in there. Radiation levels went up and they thought they might have managed it, but then they went down again.

They used a 4-ton truck to transport the air compressor and generator to the valve, arriving around 12:30. It took them until 14h to get it working. The radiation increased and they saw some white steam: success! Not a really happy success, but better-than-explosion success!

MEANWHILE, remember those freshwater cisterns that weren't going to last forever? They ran out a little before 3pm. Fortunately despite lack of sleep and extreme stress the ERC saw this coming.

Seawater was not an ideal solution because salt would eventually corrode the reactor. But nothing about this situation was ideal.
The other problem with seawater was the sea wall was so high the fire engine hoses COULD NOT REACH THE SEA. It was a very big tsunami.

Oh wait I forgot it wasn't just that salt would corrode the reactor: it could cause recriticality (means could restart the nuclear fission cycle). Anyway, they decided it had to be tried.

They started setting up a line to the backwash pit and at 15:18 Yoshida was able to tell the govt that venting had succeeded! Also, they had finally found high voltage cables to connect an electricity vehicle to the power center! [dun dun DUN]

At 15:36, there was an explosion in the reactor 1 building.

I have to take a break, but I appreciate everyone's interest and I'll be back! Don't forget the event at @strandbookstore in a couple of hours for @divyastweets fantastic new book MACHINEHOOD! Very relevant if you're into this thread! strandbooks.com/events/event18…

As with the tsunami, the people at the plant did not know what the explosion was or where it happened. The operators called ERC to ask, but they weren't sure yet either. (Can you IMAGINE? At the plant, in a room with no windows, knowing meltdown is happening, and an explosion??)

ERC called back a few minutes later to say the 5th floor of the Reactor 1 building was gone. A few people were injured by debris (RADIOACTIVE DEBRIS); everyone was pulled back from work. The electricity and water lines they had been working on were damaged.

There was even some damage to the earthquake resistant building where the ERC was, affecting the filters that were supposed to keep them safe from radiation.
Again, just amazing that they didn't all run screaming at this point.
But they didn't. at 17:20 they went back to work.

They were trying to get the seawater line set up again. Politicians were still impatient; at 17:55 a minister "ordered" them to fill the reactor with seawater, like making it an order was going to help anything or have any effect at all.

Meanwhile the PM was a little nervous about the salt and recriticality thing, and the TEPCO liaison at the PM's office assured him he would get the answer to his questions before they went forward with the seawater injection. <.<

At 19:04 - three and a half hours after the explosion - the line was repaired and they started injecting seawater into the core.
19:15 they tell the govt, but PM's in a meeting so it doesn't get to him. When the meeting finishes, TEPCO liaison calls HQ with the PM's questions

about seawater injection and is told IT'S ALREADY HAPPENING.
Loses it. Tells them they have to stop injecting until they get PM's approval.
Yoshida disagrees, but the TEPCO HQ overrides him.

Let me pause a moment to quote from the ICANPS interim report on the subject of TEPCO's emergency policy: "TEPCO’s action plan stipulates that if a nuclear emergency arises at the Fukushima Dai-ichi NPS, decisions regarding individual and specific responses are
entrusted to that

NPS’s site superintendent in his/her capacity as nuclear emergency preparedness
manager. The emergency response center at the headquarters is, when required, to provide
guidance and advice to the NPS, receives and acts upon requests from the NPS,” etc

But everyone's freaked out because the PM had some questions - didn't even tell them not to inject, as I read it, just wasn't sure - and they override the person that their own rules say should be in charge.

I don't have to emphasize here how Yoshida wasn't sure they'd be able to restart if they stopped, or whether they had the time to spare. No fool, he tells the workers to continue the injection, then gives the order to stop so it's audible to TEPCO HQ over the teleconference line.

At 19:27 TEPCO informs authorities that they stopped the injection pending PM approval, but the liaison manages to get at the PM without him hearing that (or such is the story that is told), answer his questions, and get his approval for seawater injection.

At 20:20 Yoshida gave the order to restart the saltwater injection that had never been stopped.
(They ended up adding boric acid to it to prevent recriticality)

That pretty much stabilized reactor 1. It's not the end of the story by any means: AFAIK the decommissioning process continues to this day, not even to mention the unsolved problem of nuclear waste. But it's the end of that part of the crisis for that reactor.

There are more incidents of courage and desperation and near-misses and institutional & political comemierdería in the stories of reactors 2 & 3. I might go through those too but I will start a new thread to do so.

A technical correction!

https://twitter.com/Kythrain/status/1367655029398794241?s=20

Here is the thread for Reactor 2

https://twitter.com/m_older/status/1367083689864265729?s=20

and for reactor 3

https://twitter.com/m_older/status/1367462884226260993?s=20