Talks

The Magnitude 9.1 Meltdown at Fukushima

It was mid-afternoon on Friday, March 11, 2011 when the ground in Tōhoku began to shake. At Fukushima Daiichi nuclear power plant, it seemed like the shaking would never stop. Once it did, the reactors had automatically shut down, backup power had come online, and the operators were well on their way to having everything under control. And then the tsunami struck. They found themselves facing something beyond any worse-case scenario they imagined, and their response is a study in contrasts. We can learn a lot from the extremes they experienced about finding happiness and satisfaction at work.

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00:00:00.000 ready for takeoff
00:00:16.920 thank you so much for being here my name is Nicholas means I am
00:00:23.220 the lead of the engineering team at Sim where we're building tools to create engine for engineering teams to create and orchestrate slack-based access and
00:00:30.180 authorization workflows so if you've got production system access challenges come find me we should talk
00:00:35.520 I also co-host a podcast called managing up if you're into managing stuff management stuff you might be interested in it check it out at managing up dot
00:00:42.360 show today though I'm here to tell you a story dotted along the coast of Japan usually
00:00:49.500 a significant distance from the water are Stones like this one left there by Anonymous members of
00:00:54.719 previous generations and they all say something very similar a home built high is children's relief
00:01:02.340 remember the disastrous giant tsunami do not build homes below here
00:01:07.860 now Japan is one of the most seismically active countries on Earth built on the Pacific Ring of Fire these Stones make
00:01:13.500 it obvious that they are also no stranger to tsunamis massive ocean waves driven by earthquakes under the sea
00:01:19.320 so given the risk of tsunamis you might be surprised by this map of nuclear power plants in Japan
00:01:25.020 every single one of them is right on the coast why is that well when you picture a nuclear power
00:01:31.259 plant what Pops to mind it's probably something like this
00:01:37.920 and credit to The Simpsons this actually is a fairly accurate rendering of a two unit pressurized water nuclear power
00:01:43.380 plant but the thing in this picture that you probably most closely identify with nuclear power is the two hyperboloid
00:01:49.200 cooling towers Standing Tall over the rest of the plant now the funny thing about this is that there's nothing inherently nuclear about
00:01:55.200 them every thermal power plant nuclear fossil fuel needs a source of cooling there are plenty of non-nuclear power
00:02:01.560 plants that use hyperbola towers and plenty of nuclear plants that use other kinds of cooling like these mechanical draft arrays
00:02:08.520 the post-war economic boom in Japan meant that by the 1970s Japan was starving for electricity
00:02:14.760 we need to build a bunch of nuclear power plants in a hurry and on a budget one of the best ways to reduce time and
00:02:20.040 cost is to build them on large bodies of water to use the ocean as a giant heat sink so you don't need cooling towers at
00:02:26.580 all and that's what Japan did over and over again one of those plants on the sea with no
00:02:32.459 cooling towers is Fukushima daichi a six unit boiling water nuclear power plant with a generating capacity of 5.3
00:02:38.520 gigawatts owned and operated by the Tokyo Electric Power Company or tepco it's located right on the Pacific coast
00:02:44.760 in Northeast Japan the reactors at Fukushima daichi went online between 1971 and 1979 all of them
00:02:51.420 boiling water reactors designed by General Electric in the United States unit 1 is a slightly smaller older
00:02:56.879 design than the rest of the fleet unit 6 is a slightly larger newer design March 11 2011 started like any other day
00:03:03.720 at the plant units one two and three were all running as they say in the nuclear industry hot straight and normal running at full power generating
00:03:10.260 electricity unit 4 was offline being refueled units five and six had both just finished being refueled and were
00:03:15.959 undergoing testing in preparation for for restarting but off the coast of Japan and the
00:03:21.959 Earth's crust trouble had been brewing for more than a thousand years as the Pacific Plate continually
00:03:27.840 subducts under the akhotsky plate that tohoku and the rest of Northeastern Japan sit on potential energy is built up like a
00:03:34.260 spring being compressed on March 11 2011 at about 2 46 in the afternoon that potential energy finally
00:03:41.459 overcame the friction between the plates holding it back and became kinetic energy in the form of a magnitude 9.1
00:03:48.360 earthquake the Epson was about 45 miles off the coast but subduction zone Mega thrust
00:03:53.580 Quakes like this one typically involve a rupture along hundreds of miles of fault line in this case the fault line that
00:03:58.920 ruptured roughly parallels the northern coast of Japan the force of this rupture was such that
00:04:04.319 Northern Japan moved about eight feet closer to North America and the tilt of the Earth's axis shifted
00:04:10.739 somewhere between 6 and 10 inches we're not really sure it was the most powerful Quake to ever
00:04:16.500 strike earthquake prone Japan when the shaking started masal Yoshida
00:04:21.660 director of Fukushima daiichi was in his office processing some of the paperwork that was ubiquitous in the tepco bureaucracy
00:04:26.880 Yoshida kept expecting the shaking to taper off but it just got stronger
00:04:31.919 for six long minutes the ground shook
00:04:36.960 when it finally stopped he knew there would be much to be done so he threw on his hard hat ran out of his office he fought his way through this mess right
00:04:42.540 outside his door and headed towards the plant's earthquake proof Emergency Response Center
00:04:47.639 the control room for units one and two was in disarray right after the quake as the shaking stopped The Operators immediately ran to the panels and
00:04:53.580 started figuring out the state of the plant calling out various measurements to akua azawa the shift supervisor in
00:04:58.680 charge of units one and two that day they were able to quickly see that the plant's automated emergency systems had
00:05:03.900 done exactly what they were supposed to do now to understand what happens next you need to know a little bit about how
00:05:09.300 nuclear reactors work so let's do a crash course the heart of any thermal power plant is
00:05:14.400 the heat source in a nuclear reactor it's the uranium fuel rods that create the heat generating nuclear chain
00:05:19.560 reaction the fuel rods are contained in a pressure vessel and surrounded by water that in a Boiling Water Reactor boils to
00:05:25.500 steam at the top of that pressure vessel and there are also Neutron absorbing control rods that can be inserted in the
00:05:30.900 core to slow or stop the chain reaction as water boils to steam at the top of the reactor vessel it expands and the
00:05:36.600 energy from that expansion turns a Turman connected to a generator this is how the plant actually generates electricity
00:05:42.900 as after the steam turns the turbine it's directed into a condenser where it turns back into liquid water and then a
00:05:48.479 circulation pump pumps that liquid water back into the Reactor Core this is crucial because water constantly boiling
00:05:54.479 to steam at the top of the reactor pressure vessel has to be continually replaced to keep the fuel rods from
00:06:00.000 overheating and Fukushima daichi like most nuclear plants there are sensors to detect Earth movement when there's an earthquake the
00:06:06.240 reactor control system automatically scrams the reactor putting the control rods all the way into the core and instantly halting the nuclear chain
00:06:11.759 reaction this happened exactly as it was supposed to in all three active reactors
00:06:17.220 but the fuel in the core of a nuclear reactor gets so hot that cooling circulation must be maintained for days
00:06:23.400 after shutdown to continue carrying this Decay heat away from the fuel so the fuel rods don't melt
00:06:29.039 only once that cooldown has happened has the plant reached a safe state of cold shutdown
00:06:35.699 that means the reactor's circulation pumps must be kept running even though the core is shut down and that's a problem when a giant earthquake has
00:06:42.300 severaged your plant's connection to the electrical grid thankfully the plant had redundant answers to this situation first each
00:06:49.020 reactor has two enormous diesel backup generators just one of which provides adequate energy to maintain circulation
00:06:54.660 through the core these generators had all started automatically as soon as the plant lost its grid Connection in case in case the
00:07:00.600 generators failed each control room also had a bank of lead acid batteries to power instrumentation and control valves
00:07:05.880 for several hours second each reactor had a passive cooling mechanism that would function without any external power at all in
00:07:12.600 unit 1 that took the form of an isolation condenser it was a large tank of water open to the atmosphere Steam
00:07:18.060 from the reactor pressure vessel could be directed through a heat exchanger in the isolation condenser where it would
00:07:23.160 turn back into water and Flow by gravity back into the pressure vessel with the water in the isolation condenser boiling off to steam in the atmosphere to
00:07:28.860 release the Heat the isolation condenser could passively cool unit one for three days before
00:07:33.900 requiring more water to be added without any human intervention at all the slightly newer units two and three
00:07:39.780 because they're larger have a different passive cooling system the Reactor Core isolation cooling system or rixi for
00:07:45.120 short the rixxy is a more complicated system but the basics are that the steam from the reactor pressure vessel drives a
00:07:50.520 pump that replenishes the water in the Reactor Core it can be topped up from an external tank if the water level drops
00:07:56.940 when the backup generators kicked on at Fukushima daichi these passive cooling systems all kicked into gear as well
00:08:02.220 at this point despite being without power from the electric grid the plant was well on its way to a controlled
00:08:07.380 shutdown everything was well in hand when the first tsunami warning went out
00:08:13.680 a few minutes after the Quake the initial prediction for the Fukushima area was just around 50 centimeters 18 inches
00:08:19.620 that would later be revised several times but never beyond the plant's 19-foot tall sea wall
00:08:24.660 they made a precautionary announcement over the plant's PA system that there was a tsunami warning and that workers should move to Higher Ground just in
00:08:29.879 case but that was the extent of their preparations in reality
00:08:35.459 the largest of the three tsunamis heading towards the plant was more than 40 feet high and it was
00:08:41.399 moving at 100 miles an hour when it arrived the operators in the
00:08:47.100 windowless control room had no idea they were shocked when one of the operators announced a new critical alarm at 3 37
00:08:52.860 PM the diesel generators have tripped a few seconds later the overhead lights in the control room
00:08:58.800 went out then slowly randomly panel by panel their instruments all went dark
00:09:06.300 the constant warbling of alarms from the unhappy plant was replaced by an eerie silence a few seconds later izawa broke the
00:09:12.420 Silence by shouting station blackout they had no electricity at all
00:09:17.940 a situation never considered realistically possible in all of their emergency preparations
00:09:23.160 the reactors at Fukushima daiichi are located on the 10 meter level 10 meters above sea level the huge diesel backup generators along
00:09:29.760 with the power switching equipment and lead acid backup batteries were all in the basement of the auxiliary building
00:09:34.920 on the four meter level when the tsunami arrived and inundated their sea wall
00:09:40.320 they were all destroyed The Operators found themselves trying to operate three nuclear reactors that just
00:09:46.500 minutes before had been generating over two gigawatts of power with no instrumentation
00:09:52.260 and no remote valve controls their immediate concern was unit one
00:09:57.540 the operating manual for unit 1 said that to protect the reactor's pressure vessel the reactor's cooldown rate couldn't exceed 55 degrees Celsius per
00:10:04.140 hour about 20 minutes after the Quake The Operators realized that it was cooling too fast and so they'd begun cycling the
00:10:10.140 isolation condenser in and out of service they had just cycled the condenser back off at 3 34 pm
00:10:17.459 three minutes before they lost power the rixi systems in unit two and three would keep them under control for the
00:10:23.279 time being but unit one because of unlucky timing was completely without Cooling
00:10:30.180 without coolant circulating carry heat away all of the water in the core will boil the Steam and this causes a couple
00:10:36.480 of things first without cooling the nuclear fuel rods will eventually get hot enough to melt
00:10:42.060 second because water expands when it turns to steam the pressure in the pressure vessel Rises
00:10:47.760 if pressure gets high enough it will eventually turn into a giant steam bomb and explode
00:10:54.839 spraying radiation into the environment now given fukushima's location that could make Tokyo uninhabitable for
00:11:01.440 decades that fact was in the back of everybody's mind there are a few things they needed to do
00:11:07.260 to get unit 1 back under control and they started working on them all at the same time first they knew the instruments in the control room would
00:11:13.200 work under DC power so while one team began looking at wiring diagrams to figure out how to how to hook up electricity to all their instrumentation
00:11:19.620 another team went out and began harvesting car batteries from the cars parked around the site
00:11:25.380 well they worked on that another team began working on figuring out how to get unit get water into the core of unit one
00:11:30.839 of the first things that plant director Yoshida had done when the tsunami hit was to request fire engines from two nearby Japan self-defense floor spaces
00:11:38.279 now this wasn't in the plant's emergency operations manual but Yoshida predicted correctly that they would need some way
00:11:44.940 to pump water and fire engines were the first thing that came to mind meanwhile katsuaki hirano had just
00:11:50.880 arrived at the unit one control room he was a shift supervisor from a different team he wasn't scheduled to work that day at all but he had made his way to
00:11:57.300 the plant to help as quickly as he could after the earthquake he had the idea of using unit one's firefighting pipe Network to Route water
00:12:04.260 to the Core he led multiple Expeditions into the dark reactor building to manually turn the five valves necessary to Route water
00:12:11.459 from the fire pipes into the core ano and a partner returned from their final Expedition
00:12:17.100 around 9pm by 11 pm radiation levels at the reactor building airlock were so high that
00:12:24.120 further entry was prohibited by Yoshida so it was fortunate that hirano's expedition was one of the first things
00:12:29.279 that the operating crew did the plant had three fire engines on site one of them had been destroyed by the
00:12:35.640 tsunami a second couldn't get to unit one because of tsunami damage to roads the third however was just behind an
00:12:41.279 electronic security gate at unit three but electronic Gates don't work with the power out
00:12:46.380 by around two in the morning they finally broken the lock on the security gate moved the fire truck into place and
00:12:52.079 had begun injecting water into the core of unit 1. unfortunately the water injection they
00:12:58.380 were able to accomplish was very slow because of pressure in the reactor vessel once they worked out how to hook
00:13:03.839 a hook up the scavenged car batteries to the instrumentation and control room they found that pressure in the pressure vessel was significantly elevated around
00:13:10.500 two atmospheres of pressure the only way pressure this high would have been possible was if the fuel had
00:13:16.260 begun melting down so relieving the pressure and getting more water in was absolutely critical
00:13:21.839 thankfully Yoshida had anticipated this as well and was already working on the necessary permissions to conduct event
00:13:27.240 now this is exactly what it sounds like venting likely radioactive Steam from the pressure vessel of the reactor into
00:13:33.120 the open atmosphere it was it was a worst case measure to try to save the plant
00:13:38.399 any atmospheric release of radiation required government permission and that permission needed to come from this man
00:13:43.740 naoto Khan the prime minister of Japan as soon as an emergency had been declared at the plant tepco sent a
00:13:49.320 liaison to Khan's office so he had already been briefed on the rising pressure at unit one he readily gave permission for the vent
00:13:55.680 as soon as the five kilometer evacuation Zone around the plant was evacuated a process that was already underway
00:14:03.180 at the plant izaw and his team had been working feverishly and rapidly deteriorating conditions to figure out how to vent the reactor radiation levels
00:14:09.899 were now high enough in the control room being there required wearing full face masks with charcoal filters if radiation was this bad in the control
00:14:16.380 room it would be terrible and dangerous in the reactor building they needed to
00:14:21.720 figure out a way to vent the plant that would have staff in and out as quickly as possible
00:14:26.820 back in tokyocon had finished his middle of the night emergency press conference to announce the vent and he was livid
00:14:32.519 it was four in the morning he'd given us permission to vent hours ago why the hell hadn't they vented unit
00:14:37.680 one yet did they not know what was at stake the tepco yet liaison in his office had
00:14:42.720 explained the challenges the staff of the plant were facing but Khan decided he needed to find out for himself what was going on
00:14:49.740 so by 5 30 in the morning the day after the earthquake the Prime Minister and his Entourage ran a helicopter on their
00:14:55.740 way to Fukushima daiichi at the Fukushima Emergency Response Center there was panic and frustration
00:15:00.959 over Khan's visit Yoshida and his staff were now working feverishly to vent unit one and now they had this to deal with
00:15:08.579 on top of that they had another problem to solve they were running short of protective equipment and now that the pre the PM and his
00:15:14.339 Entourage were coming they had to outfit them as well with their dwindling stocks every time someone entered the radiation
00:15:20.100 shielded ERC the face mask that they were wearing had to be discarded because as soon as the seal with their face was
00:15:25.260 broken it was contaminated it was decided that Khan would land at a nearby sports field and that he and his
00:15:31.139 Entourage would be brought as close to the door of the ERC as possible in a mini bus so that they wouldn't need to
00:15:36.959 waste Emergency Equipment on them it was a clever solution tepco VP takaimuto was among the party
00:15:43.560 to greet Khan's helicopter when it landed in Fukushima Muto remembers offering kana's standard Japanese greetings very formal along the lines of
00:15:51.120 it's very kind of you to come sir now I'm sure he didn't feel this way but that's what Japanese etiquette dictated
00:15:56.459 that you said to the prime minister in a situation like this Khan quickly responded why the hell
00:16:02.220 haven't you vented yet he proceeded to yell at Muto for the entire bus ride to the Emergency
00:16:08.880 Response Center remembers Khan saying repeatedly that he just wanted to know what the problem was
00:16:14.040 but then not listening at all he seemed to only want to complain that staff weren't doing their jobs
00:16:19.199 when Yoshida and Khan met in the ERC Khan's first words to him what the hell is going on
00:16:24.660 rather than Fight Fire with Fire Yoshida calmly explained the situation in detail and as he talked Khan seemed to settle
00:16:32.220 finally Khan asked well when are you going to get the vent done more than anything else you must get the vent done
00:16:39.480 Yoshida responded calmly again we are of course doing everything we can we have a Suicide Squad preparing to
00:16:45.720 enter the radiation field now hearing that there were people willing to risk their lives to conduct the
00:16:51.600 dangerous event operation seemed to end the discussion the actual meeting had lasted 20 minutes
00:16:58.500 asawa's crew had identified a pathway to venting that would require only require opening two valves the valves were in
00:17:04.199 two different areas of the reactor building so they would send two teams of two into the radiation field under
00:17:09.900 Japanese law workers are allowed a maximum of 100 millisieverts of radiation exposure during an emergency so everyone put on a personal dissimeter
00:17:16.380 alarm like this one and set it to go off at 80 millisieverts agreeing to turn back immediately if it went off
00:17:21.540 the first crew made their way to their valve on the second floor of the reactor building it was huge awkwardly placed at the end of a catwalk hard to turn
00:17:28.500 but they got it done and we're back to the control room in 11 minutes without coming close to the the 80 millisievert
00:17:33.960 alarm the second Cruise valve was in a much more precarious position
00:17:39.120 to help us understand here's a photo of an under construction Mark 1 containment structure the thing represented in this
00:17:44.340 diagram from earlier their valve was in the basement of the reactor building
00:17:50.280 if there had been core damage it was likely that melted fuel would be sitting at the bottom of the pressure vessel
00:17:55.919 creating an intense radiation field at the bottom of primary containment as they made their way into the basement the handheld radiation meter They
00:18:01.919 Carried was bouncing between 900 and 1000 millisieverts per hour roughly enough to give them their Max dose in
00:18:07.140 about 10 minutes when they saw the meter stick at a thousand millisieverts per hour the max that it could read
00:18:12.780 they had to turn back there was no way to know how strong the radiation Fields they were walking into were with their
00:18:17.940 meter maxed out when they got back to the control room they found that they had received a doses of 89 and 95 millisieverts
00:18:25.440 respectively they were the first two workers to dose out and have to be evacuated from the site
00:18:31.980 nearly 10 in the morning and the event still hadn't been carried out the operators had gone from elated at the
00:18:37.020 success of the first crew to despondent at the situation the second crew encountered they didn't give up
00:18:43.140 there had to be a way to vent it one group worked to see if a portable air compressor could remotely operate the
00:18:48.179 pneumatic valve while another tried to find a different route to the valve at two in the afternoon the reactor
00:18:54.000 pressure vessel was up to eight atmospheres of pressure about two times its rated strength
00:19:00.000 things were getting desperate the second crew was just getting ready to make a run for the valve determined to open it no matter what the cost when
00:19:07.080 they got a call from the ERC white smoke was coming out the top of the unit one and two shared event stack
00:19:13.919 slowly pressures in the reactor pressure vessels started to drop they must be venting
00:19:18.960 there was no way they could know for sure without instrumentation but the attempt to open the valve pneumatically must have worked they felt a tremendous
00:19:26.100 sense of relief that relief would last for about an hour
00:19:31.440 this is what an off-site monitoring camera saw at 3 36 pm on Saturday March the 12th
00:19:36.840 workers scrambled upon protective gear to figure out what had happened their initial fear was that venting the reactor was too little too late and the
00:19:43.320 reactor pressure vessel that just exploded but thankfully that wasn't what had happened
00:19:49.740 this is what a fuel bundle looks like for a Boiling Water Reactor a given reactor would have several of these
00:19:54.840 bundles arranged in its core for optimal reactivity most of the tubes you see here are the actual fuel rods made of zirconium alloy
00:20:02.220 and filled with uranium fuel pellets now zirconium is the metal of choice for this because it's very corrosion and
00:20:07.380 heat resistant while also being essentially transparent to the neutrons that sustain the nuclear chain reaction as the core gets hot enough to melt it
00:20:14.160 though it's corrosion resistance runs out and it starts rapidly oxidizing
00:20:19.799 and a reactor pressure vessel filled with steam the sudden oxidization reaction rips the surrounding water molecules apart forming zirconium oxide
00:20:28.140 and hydrogen gas which is very flammable as the smoke and debris settled this is
00:20:33.780 what they saw given the shaking of the earthquake and the significant over pressurization of the reactor's primary containment it's likely there were
00:20:40.200 plenty of places the hydrogen created by the Meltdown could have slipped through it accumulated at the top of unit 1's containment building and all it took was
00:20:46.799 one Spark the explosion blew radioactive debris across the site it also caved in a door
00:20:52.980 and an air conditioning intake at the Emergency Response Center contaminating the one relatively radiation free space
00:20:58.559 remaining on the site the work of keeping units two and three from melting down got that much harder
00:21:05.340 and circular the situation at unit three was getting pretty critical the rixie had been passively cooling the reactor
00:21:10.440 since the power loss but heat was starting to build and they were running out of fresh water on site Yoshida made the call to use fire trucks
00:21:16.740 to begin injecting sea water they've been trying to avoid this because they were still hoping to restart their reactors someday and the
00:21:23.400 salt in the sea water would ruin the reactor meaning it could never generate power again but they had to keep it from exploding
00:21:29.280 that was the priority back in Tokyo prime minister Khan heard that they were considering sea water injection and demanded that they not do
00:21:35.580 it one of his small group of technical advisors had mentioned a non-zero chance that the salt in the seawater might
00:21:41.940 cause the reactor to start reacting again to become critical in reality the chance was minuscule and an
00:21:47.460 exponentially smaller risk than a reactor explosion Masala Yoshida had no intent of
00:21:53.940 complying before a video conference with tepco execs in Tokyo he told his staff if they
00:21:59.159 order me to Halt seawater injection I will relay the order to you so that they can hear me you are not to respond and you were not
00:22:06.720 to stop seawater injection it's our only chance unbeknownst to them core damage at unit
00:22:12.900 3 had already occurred and if they had stopped the seawater injection it might well have exploded
00:22:18.179 the next day unit 3 would experience a hydrogen explosion just like unit one unit four which wasn't even running at
00:22:24.059 the time of the earthquake would go on to explode as well from hydrogen gas suspected to have leaked in from unit 3 via their shared vent stack
00:22:30.960 they later later learned that unit 2 had experienced core damage as well and it likely avoided a hydrogen explosion only
00:22:37.080 because its reactor building was damaged enough from the other two explosions to vent the hydrogen instead of letting it accumulate
00:22:43.320 you can see units one through four in this photo three of the four exploded three of the four in a state of partial
00:22:49.860 meltdown at this point radiation levels at the site were making it hazardous to walk from building to building with staff
00:22:55.380 running everywhere they needed to go wearing heavy protective gear so late in the evening of the 14th
00:23:00.900 Yoshida made the difficult decision to evacuate most of the staff to Fukushima daini daiichi's sibling plan a few miles
00:23:06.600 away and only keep a volunteer Skeleton Crew on site Yoshida didn't allow anyone under 45
00:23:12.240 years old to stay because people under 45 might still have children and radiation poses more danger to them
00:23:18.299 those over 45 were free to leave as well if they wanted nobody was forced to stay everyone who chose to stay knew that
00:23:24.360 there was a significant chance they'd suffer dangerous radiation exposure possibly even die
00:23:30.659 but they felt the responsibility of the rest of Japan to ensure that the plant didn't cause wider contamination
00:23:36.659 in the end there were 68 plus Yoshida left at the plant
00:23:41.940 this group would be referred to by the media as the Fukushima 50. back in Tokyo prime minister Khan heard
00:23:47.940 that conditions of the plant were deteriorating and shockingly the tepco planned to abandon the plant they can't do that it would surely
00:23:54.419 explode furious at the news Khan calls a middle of the night meeting the tepco liaison a Khan's office
00:24:00.960 quickly clarifies the misunderstanding that there's no intention of abandoning the plant just evacuate non-essential personnel
00:24:06.720 but it doesn't matter Khan is finished at this point he uses his authority to create a joint
00:24:11.940 response office with himself as the lead taking over control of the response at Fukushima from tepco
00:24:17.460 despite knowing that there was never any intention to abandon the plant Khan carries on like there was in the internal video conference announcing the
00:24:23.220 change if things go on like this Japan is done for abandoning the plant is Unthinkable
00:24:28.740 you must risk your lives on it if necessary if you abandon the plant tepco will be destroyed you can run but you'll
00:24:36.059 never get away these were his words to a room full of people who had just decided to sacrifice
00:24:42.600 their lives if necessary to save this plant at this point masal Yoshida had had
00:24:49.020 enough at the front of the room video conference cameras still running
00:24:54.419 Yoshida stands up turns his back on the prime minister and lowers his pants
00:25:02.400 he makes it look like he's just tucking his shirt back in but everyone in the room knows what he's really doing in Japan's formal business culture
00:25:08.760 turning your back on a superior is a huge etiquette faux pas but Yoshida took it exponentially
00:25:15.240 further than that now as the plant slowly came further and
00:25:20.940 further under control and danger became less evacuated workers came trickling back in to help it would take the better part of the year but finally on December
00:25:27.480 16th tepco declared cold shutdown at Fukushima all reactors were below 100 degrees Celsius and all radiation leaks
00:25:33.779 had been substantially contained this photo from earlier this year shows the condition of the plant today
00:25:39.000 a tank farm sprang up around the plant to contain all the contaminated water unit 1 and 2's buildings were able to be
00:25:44.100 repaired but new containment structures had to be built around units three and four decommissioning work has begun and will
00:25:49.740 likely take the next 30 to 40 years to complete in the history of new commercial nuclear
00:25:55.200 power generation there have only been five reactor meltdowns three of these were at Fukushima to fully understand
00:26:01.080 the severity of the accident let's put it into context by comparing the amount of radiation it released into the environment
00:26:06.480 the first commercial reactor to partially melt down was at Three Mile Island in Susquehanna Pennsylvania
00:26:11.720 Islands contained Hydro hydrogen explosion and subsequent venting released approximately 626 gigabyte
00:26:18.059 rolls of radiation into the atmosphere Fukushima daichi with its three partial
00:26:24.179 meltdowns and three uncontained hydrogen explosions is estimated to have released 780 petabek rolls of harmful radiation
00:26:30.900 Three Mile Island is represented as a one pixel dot here I promise it's there but the correct side on this slide would
00:26:37.080 actually be a circle 6 10 millionths of a pixel across that's how much larger Fukushima was to through Mile Island
00:26:45.059 but compared to the largest nuclear accident of all time Fukushima looks pretty small
00:26:51.720 Chernobyl a Soviet rbmk reactor designed famously with no containment of any kind
00:26:57.179 had exploded and there was nothing to keep it from going straight up into the atmosphere to the tune of 5.2 exobecerals around seven times as much
00:27:04.919 radiation as Fukushima it was a huge accident but let's say that the operators at Fukushima had
00:27:11.279 failed to establish Cooling and relieve the growing pressure in their containment vessels and all three running units at Fukushima
00:27:17.279 experience steam explosions an uncontained failure at all three Fukushima daiichi units would have
00:27:23.100 released at least 7.5 exabec rules but because fukushima's reactors had
00:27:28.740 pressure vessels it's likely that would have Amplified the explosions compared to what happened at Chernobyl
00:27:35.340 it's almost impossible to guess how bad the accident at Fukushima could have been
00:27:40.559 if not for the heroic actions of Masala Yoshida Iko izawa and all of the other Brave operators who risk their personal
00:27:46.860 safety at Fukushima to mitigate the accident the only way to have prevented this disaster
00:27:52.679 would have been to move the backup generators to Higher Ground something that tepco was studying but hadn't yet
00:27:57.960 committed to do at the time of the accident it's almost impossible to improve upon the actions The Operators took in the
00:28:04.620 minutes hours and days after the accident so there's nothing The Operators could
00:28:09.779 have done differently to get a better outcome what should we learn from the accident at Fukushima let's talk about nautokan
00:28:17.220 Khan resigned on September 2nd 2011. in no small part because of the situation at Fukushima daiichi not just that it
00:28:24.240 happened but his handling of it his distracting visit the morning after the earthquake
00:28:29.760 his attempted delay of seawater injection his demoralizing pep talk insulting the very people Japan was
00:28:35.820 depending on to keep the crisis from escalating in each case there was one man that countered Khan
00:28:41.880 Masala Yoshida both shielded operators from Khan's interference and rallied them past it when it was unavoidable he
00:28:48.600 deftly handled Khan's site visit he ignored Khan's order to pause seawater injection he very tangibly showed the
00:28:53.820 Fukushima 50 that he would not stand for Khan's disrespect
00:28:58.860 and he did all of this in a culture her seniority and hierarchy are sacrosanct
00:29:05.520 how a really interesting paper published by Dr Ruth Ann heising has some insight for us Dr heising interviewed several
00:29:12.659 employees who were participating in business process redesign teams at large companies these teams were working to make fundamental changes about how their
00:29:18.659 organizations worked part of the process each of these teams went through was process mapping
00:29:23.760 documenting the steps conversations tools and other activities required to complete a Core Business activity like
00:29:29.039 processing an insurance claim or launching a new product these Maps were always surprising for
00:29:34.080 the teams that created them and they often raised existential questions about employees roles in the organization
00:29:39.419 the reason was that they revealed the actual structure of the organization the relationships the information Pathways
00:29:45.899 that were responsible for the organization actually being able to get work done they learned the actual structure of the organization was an organic emergent
00:29:52.679 phenomenon constantly shifting and changing based on the work to be done and often bearing little resemblance to
00:29:58.620 the formal hierarchy of the organization observing the organization is
00:30:03.720 continuously in the making gave employees an overwhelming sense of possibility sparking ambition their
00:30:09.539 experience with the mapping exercise shook them out of their well that's just the way things are learned helplessness towards the bureaucracy and the way that
00:30:15.659 their companies worked we've all trained ourselves over the course of our careers to think that the
00:30:21.480 folks at the top of the org chart know more than we do and they often do have helpful holistic
00:30:27.960 perspective about the company and the industry it operates in but all of the actual work of an
00:30:34.320 organization all of its output happens at the bottom of the org chart and the teams at the edge of the organization
00:30:40.500 leaders at the top may have a wide perspective but the edges are where an organization's detailed knowledge lives
00:30:45.779 and because of that the edges are where the majority of an organization's decisions ought to be made this is where
00:30:51.000 the organic emergent structure that lets an organization actually get work done takes shape
00:30:56.760 which brings us back to yoshida-san ryushu kadoda the author of one of the books I read researching this
00:31:01.980 presentation asks several Fukushima workers how the accident would have been different without Yoshida and most of them answered with some variant of we'd
00:31:07.740 have been lost without him several said something like with Yoshida in the lead we were prepared to die together if we had to
00:31:13.679 when asked why it came down to trust Yoshida made it clear over his years of leading Fukushima daichi that he trusted
00:31:20.100 his operators and their decisions they were able to make decisions and work in such Harmony during the accident but
00:31:25.679 because of the trust he placed in them and Yoshida continually re-earned and
00:31:31.620 reinforced their trust by doing things like standing up to the prime minister
00:31:37.200 so what's the takeaway well depends on who you work for
00:31:43.020 if your management resembles naotocon you're going to have to lean into what the participants in Dr heising's
00:31:48.600 business process mapping exercise learned I'm now focused on inventing the board and not just playing the game
00:31:55.500 trying to see what's really out there and not arguing too much for the limitations that maybe aren't so real
00:32:01.919 you can see this in the way that Yoshida responds to Khan the rules of the game especially in Japan are extreme
00:32:08.159 deference to hierarchy and superiors but the possibility Yoshida was fighting for was not blowing up the plant
00:32:15.659 it's not all Rebellion all the time but it might mean knocking your deference for your leaders down a notch or two and
00:32:22.320 trusting yourself a little bit more so that you can get work done but if your management is more like
00:32:28.080 masal Yoshida your job is to lean into the trust that they give you to try things to use the safety that they
00:32:33.720 create and the guidance they offer to learn and to grow and to push the business forward
00:32:38.760 you likely still have some learned helplessness built up from your career and even with high trust leadership you're still going to have to learn how
00:32:45.779 to create the game rather than play it and if you're a leader I hope the lesson
00:32:50.940 here is obvious I can chart my career by the talks that I've given because they're always around
00:32:56.399 what I'm learning in the moment that I write them my focus right now in leading the engineering team at Sim is to see what
00:33:02.880 happens when a company's whole leadership team leans into the idea that everything important happens at the edge
00:33:08.159 of the company and the rest of us are there to support that to really trust Empower support and
00:33:13.620 guide not dictate and lead by Road our engineering team has grown more and taken on more leadership responsibility
00:33:19.679 than I would have ever thought possible and we're moving remarkably fast because of it because of that autonomy
00:33:26.039 it's been one of the biggest privileges of my career to be there for it I hope everyone in this room gets a
00:33:31.320 chance to experience or maybe even create a team like that at some point in your career good things like this