Skepticism

A Conversation with My Dad, a Nuclear Engineer, about the Fukushima Daiichi Nuclear Power Plant Disaster in Japan

My dad and I, circa 1984.

Cross-posted on my geology blog Georneys.

Update: Improved audio soon to be available for all 4 interviews. Please note that in the first interview my voice sounds strange because I used really bad recording software (free off the internet) that sped up my voice slightly and made it sound higher-pitched. I am not sure how to fix this, but please do not judge my voice until you have listened to the follow-up interviews. Yes, I have a high-pitched voice, but it’s not quite as bad as in the first interview. If my voice bothers you, please read the transcripts. Thanks!

Update: Announcing daily updates with my dad, a nuclear engineer

Update:  A third follow-up interview with my dad is now available here:

Third Follow-Up Interview with my Dad

Update: A second follow-up interview with my dad is now available here:

Second Follow-Up Interview with my Dad

Update: A follow-up interview with my dad is now available here:

Follow-Up Interview with my Dad

My dad does not usually swear. He’s usually a reserved man of few words. When my dad starts swearing and talking on and on about something, you know that he’s upset. All day yesterday, my dad kept saying “Ohhhh s&*t” when he heard the news about the Fukushima Daiichi nuclear power plant being hit by an earthquake and then a tsunami.When I interviewed my dad earlier today, he had much to say.

My dad- Commander Mark L. Mervine, US Navy– is a nuclear expert who has worked on both nuclear submarines and nuclear power plants. I wanted to find out why my dad is so concerned about the Fukushima Daiichi power plant, so I called him up just a few minutes ago and recorded the call. I asked my dad all of the questions I had about the nuclear disaster. I hope this phone interview answers some of the questions you have. If you are at all concerned about the Fukushima Daiichi nuclear power plant disaster, you MUST listen to this conversation.

I hope to transcribe this conversation later, but for now here is the audio recording:

Note: I am having trouble getting the Quick Time file to embed or upload onto YouTube. If anyone could help me, I would be most appreciative. I hope the above link works for now.

Update: thanks to Brad Go, the interviews with my dad are now up on YouTube:

Update: Transcription after the jump. Thanks so much to Skepchick readers Ashlyn and JesseW for the transcription.

Q: Are you ready for the interview?

A: I’m ready.

Q: Alright.  I was hoping that we could start out, I know who you are, since you’re my dad, but if you could just introduce yourself quickly and describe some of your background in nuclear power.

A: Sure, my name is Mark Mervine.  I graduated from the US Naval Academy in 1981, and went into the Navy nuclear power program. I was in submarines, and while I was in the Navy I qualified on two different types of Navy nuclear power plants and served as an instructor in the Navy nuclear power program.

Q: OK, and then after you got out of the Navy?

A: After seven years of active duty, I went into the Reserves, and I stayed in the Reserves and I retired as a commander in the Navy Reserves.  I went to work, initially, for Wisconsin Electric, which at that time had a 2-unit Westinghouse pressurized-water reactor in Turbridge, Wisconsin.  While I was there, I completed my SRO certification, which allowed me to do senior review and oversight, as a member of the plant management staff.  And I also qualified and served as a shift technical advisor, which is a position that was added in the nuclear power industry, after Three Mile Island, that is a degreed engineer position, that’s available to the on-shift crew on a 24-hour basis.  Some plants do it on an 8 hour watch, at that time, Wisconsin Electric did it on a 24 hour watch, so I would actually stay at the plant for 24 hours; we had a place where we could sleep, and my job was to advise the crew whenever they needed advice on what was happening with the plant.

After a few years at Wisconsin Electric, I went to work for Vermont Yankee, where I also completed the SRO certification, Senior Reactor Certification, which allowed me to do senior level reviews as a member of the plant management staff, and I also served on the Outside Review Committee, which is a very high-level committee for the main Yankee nuclear plant, until it closed, and also Vermont Yankee.

Q: Excellent. So, you’re qualified to talk a little bit about nuclear power, it sounds like.

A: I can talk a little about nuclear power, yes.

Q: OK, excellent. So, my first question for you is really basic, since maybe people are not familiar with this, but what, can you just describe quickly, what is a nuclear power plant?

A: Yes I can, maybe what I’ll do first is explain what a power plant is.

Q: Sure.

The vast majority of power plants in the world generate steam, by some method, some by burning oil, some by burning coal, and heat up water, and make steam, that steam then powers a turbine, and attached to the turbine, you have a generator, and that generator generates electricity, and through transformers is connected to the electrical power grid.

So, in that respect, a nuclear power plant is a lot like other power plants, in that you have this turbine, that’s steam driven, with a generator, that’s attached to a transformer and then to the grid. The difference is, what a nuclear power plant does, is it generates, depending on the type of the plant, hot water or steam, by the fissioning of uranium.

3:30

Q: Right.  And that’s providing the power, basically.

A: So, there’s two major types of nuclear power plants in the Western world. One is a pressurized water reactor where the water’s kept at high pressure and doesn’t boil; an there’s a heat exchanger, and on the other side of the heat exchanger, that water is allowed to boil which generates the steam. And then you have a boiling water reactor, where the water in the reactor actually boils and generates steam directly, and that steam is used to power the turbine.

4:07

Q: So, another question I have for you, is one of the main problems they’re having in Japan is that they’re not able to cool the power plant. So, can you explain why a nuclear power plant needs to be cooled?

A: Absolutely, so what happens in a nuclear power plant is that the atoms fission or split in half and that generates heat.  There’s also other materials that are created (I don’t want to get into too much detail and confuse people) that continue to decay and that also generates heat. So for some period of time after you shut down a nuclear power plant you have to continue to cool the reactor core. Because you’re still, I mean, to begin with, it was very warm because you were generating hot water under a lot of pressure or steam and it needs to be cooled, obviously, down and because of the decay of these materials in the fuel they also continue to generate heat for some period of time until the decay trails off.

5:13

Q: So they’ve actually shut down the plant in Japan and they’re just trying to cool it?

A: Okay, well if you’re talking specifics, the plant that we’re aware of that is in the most difficulty right now is the Fukushima plant, Unit One.  That plant is a General Electric boiling water reactor, it first achieved criticality in 1970, it’s similar to a couple of other plants that we have here in New England. It’s very similar to Pilgrim, which is down in Massachusetts, and Vermont Yankee, in Vermont.

And, that plant was automatically shut down, when the earthquake occurred, and for about the first hour, they were running on their diesel generator. Once a plant shuts down, it has two ways to get electricity, one is from the grid, and another is from emergency diesel generators that they have on site. In this case, because of the magnitude of the earthquake, the grid basically went dark, so they were operating on their diesel generators and everything was functioning as it should be. But then, based on news reports, about an hour after the earthquake and the shutdown, the tsunami hit, and flooded the plant, where the diesel generators were, and that caused them to lose their diesel generator power and reduced them to their emergency battery backup power only.

6:42

Q: And that wasn’t quite enough to have the cooling capability that they needed?

A: The emergency backup on the batteries gives them, you know, very very limited capabilities, so they were having a very difficult time keeping the plant cool.

6:59

Q: Do they sort of have to go to a smaller cooling system, smaller pumps and that sort of thing, that can be run off of their battery?

A: I don’t know the specifics of that plant and what they might have done in Japan. Obviously, Japan being in an earthquake zone probably had additional requirements for the plant that we wouldn’t have to have in other places around the world. But, in any event, based on news reports, they did have some type of cooling capability using their battery power, the problem of course is, the batteries are only good for a few hours.

7:32

Q: Yeah, the news reports said that the Japanese military was actually trying to get in replacement batteries to cool the plant, I’m sure they’ve continued that effort but I haven’t heard any update on that in the news.

A: So, the reports that I saw on the news said exactly that, they were trying to supply the plant with additional batteries and a portable diesel generator.

7:52

Q: Right, I hope they’re successful soon. So how are nuclear power plants in general built to withstand earthquakes and tsunamis? You may not know about this, since you work on power plants that are in more tectonically stable regions, but are there some specific requirements for natural disasters?

A: There are, and depending on what the worst case scenario would be anticipated for an earthquake, their requirements are different. So probably the best example I could give is, I once participated in an inspection of the Trojan nuclear power plant which was in Oregon.  That plant has been shut down now, but compared to the plants that I had worked in Wisconsin and in Vermont they had a lot more requirements on them for earthquake protection. So the way you do that, there is a lot more supports for all the equipment, all kinds of hydraulic dampeners which allow the equipment to move back and forth without breaking. I know in Japan they have a requirement that all the plants have to be built on bedrock, so, they actually have to go down to bedrock in order to begin to build the supports of the plant. So, yeah, there’s numerous precautions that are taken and, like I said, there were probably additional backup system requirements that were required by the Japanese government, for those plants, being in an earthquake zone.

9:22

Q: Yeah but this was just such an enormous earthquake, I mean, I don’t think they’re released the official report yet, but this is probably in top five biggest earthquakes so even if they prepared for the absolute worst, this is something that really stressed all of their systems and backups, I imagine.

A: Well, I think really the key here was not so much the earthquake. By all reports, the plants functioned exactly as they were supposed to do in the earthquake, they shut down automatically, when the grid was lost their diesel generators started, and everything was fine. What really put us in the situation we’re in now is the tsunami as a result of the earthquake, but not the earthquake itself.

9:58

Q: So, what happened with the explosion that happened earlier today, do you know anything about that?

A: Well I can only comment on what I’ve read in news reports and a little bit of speculation based on my knowledge of how nuclear power plants work.

So again, in this case, this is a boiling water reactor, so when its operating, normally the reactor is full of water to a certain point, and then above that, steam, so the core is kept covered in water, but above that steam is generated, and that steam goes through pipes, normally, turns the turbine, and then is cooled and returned back to the reactor.

Because they’re on a very limited backup capability, only to get, probably, a small percentage of the water that they would normally be able to pump into the reactor to cool it, they were probably allowing the water to boil, which you wouldn’t do normally, during a shut down. But by allowing the water to boil you’re taking heat away from the reactor and thereby cooling it.

Because of the lack of power, they wouldn’t be able to use their normal and back up systems to remove the steam and cool it and return it to the reactor, because there was no power. So they were probably trying to vent this steam into the buildings at the plant. If they could vent a little bit of steam, add a little bit of cool water, they could keep the reactor cool enough to keep it from melting down.

11:34

Q: I see, and I guess the big question that everyone has today is, has the explosion or any of the damage, I guess there hasn’t been a lot of damage to the plant, it’s just overheating, do you think any of this is causing nuclear leakage and if so, is that a big problem?

A: So, I‘ve actually looked at the before and after picture from the explosion that’s available on the news and, in my opinion, they have an extremely serious situation at this nuclear power plant. So, my speculation is they were venting the steam in order to try and cool the reactor, unfortunately, without power they don’t have a lot of their normal instrumentation that they would have.

Q: So they can’t monitor things to the same degree —

A: They don’t even have their backup power, I mean they basically have the bare minimum of instrumentation provided by whatever battery power they have left. My guess is, and it was reported in the news that they had a hydrogen explosion, so they obviously had hydrogen and other gases that were generated, that built up to an explosive level and if you look at the photos the entire building surrounding the reactor, the only thing left of it is the steel frame, the whole building has collapsed. That would normally be called the auxiliary building, and that building actually does house a lot of the emergency systems for the reactor. So I think we have a very very serious situation at this power plant where the entire auxiliary building has been destroyed.

According to reports, the containment is intact, so if there has been any release of radioactivity, it has been very minor, to this point, but they have got to find a way to get some electricity, and cool that reactor. And the last report I saw said that there plan was to use seawater. So obviously, they’re going to get some temporary pumps, they’re going to use seawater, mixed with boron. Boron is a substance that will absorb neutrons, very similar to borax that you could go buy to wash your clothes with, that will keep the reactor from going critical again when they add the cold seawater. Even though the control rods have been fully inserted, when you add cold water, cold water is denser than warm water, and it can cause the neutrons that are still bouncing around the reactor to moderate, to a speed at which, (so moderate means slow down), they could strike the fuel and cause a fission.

We obviously don’t want any more fission because that generates more heat and we certainly don’t want the reactor to go critical because that generates a lot of heat. And, critical is not the bad word that you see in the news, where you say “Oh, reactor’s going critical!”; when it operates, it’s normally critical; all critical means is it has a self sustaining reaction, which is what you need to operate. What we wouldn’t want it to do is to go to a terminology called super-critical, that would be really bad. But in any event, when you add the cold water and you don’t add the boron, then you have the potential of causing the fission level to go up in the reactor and more heat to be generated, which you don’t want to do. This is beyond the last resort, to do this, at a nuclear plant.

Q: To use sea water to cool it —

A: I think they’re basically down to their last option here.

15:10

Q: So what do you think is the best case scenario for this plant, and added to that question, what is the worst case scenario?

A: I think the best case is that the military get the generators on-site with some emergency pumps and they’re able to rig up a cooling system to cool that reactor, to keep it cool, and they’ll have to cool it for several days before it gets to the point where the heat is decayed off. Obviously the plant is destroyed, and I’m sure it will have to be decommissioned. The question is how much additional damage is there at the site, because, there’s actually six nuclear reactors at that same site and two more that were planned or are under construction.

15:56

Q: I see, so this is just one that’s been failing.

A: This is just one of six reactors at that site that were in commercial operation.

16:08

Q: Oh that’s scary, so that there could be trouble with the other ones.

A: The question is, as a result of this explosion – has any damage occurred in any of the other, adjacent, reactors and also what is the situation of the additional reactors?

16:26

Q: Right, if they don’t cool them, it seems like this same thing could happen to them.

A: They would have the same problem, so a couple of the plants were shut down for maintenance so they’re probably less problematic because their cores would have cooled down but the ones that were operating at the time that the earthquake occurred, could all be a concern.

16:51

Q: So I guess a final question I have for you is, do you think nuclear power plants should be built in an earthquake prone area such as Japan?

A: I think it’s important for the nuclear industry, to be unemotional about what has happened here. So, like I said, it does appear that all of the design features that were required for the earthquake, functioned, and the plant was going through a normal shutdown sequence. Obviously, when the tsunami came, that was something that was not designed for, because it flooded the location where the emergency diesel generators were and caused them to lose all power, and we’re now in a scenario that’s well beyond any design contingencies that were designed for that plant.

So, I think the nuclear industry has to take a serious look at what has occurred in Japan. Although nuclear power is an important source of electricity, I think we have to seriously question any plants that are located next to the ocean and the worst case scenario for this type of event, an earthquake followed by a tsunami, as to the impact it would have on that plant, and the emergency backup system.

Clearly, in this case, this was not taken into account and the net result is, we have a nuclear plant that appears to be very very close to a core meltdown.

18:32

Q: And what would a core meltdown lead to? I mean, is this going to be contained? Is there any chance that this is going to be like a Chernobyl type situation? I mean, I know that’s a different scenario, but is there a potential for a large radiation leak here?

A:So, you ask a good question, and probably one that is on the mind of the public. So, the first thing is, this is a different scenario from the one that happened at Chernobyl.  And let me just explain a little bit. Chernobyl reactor was a completely different type of design than those that we typically have in Western society. That was a graphite moderated reactor and probably the big difference between either a pressurized water reactor or a boiling water reactor like we have in the West, is that a water cooled reactor is what we call inherently stable.

In this boiling water reactor, even though, it’s not good that the core would not be cooled, as the water level drops, and you generate steam, the steam is less dense than the water, so that means that there’s less molecules of water to moderate or slow down the neutrons. So, when a steam void forms, it actually causes the power level to drop in that vicinity, or the heat generation to drop in that vicinity.  The problem you have, of course, is you do need to cool the reactor because you have all this residual heat, but a pressurized or boiling water reactor is inherently stable, as opposed to the Chernobyl design which is inherently unstable.

The other big difference is, all Western reactors have to have a containment building. And so, according to the news reports, although the auxiliary building has been destroyed, the containment, or steel liner, has not been destroyed. So that’s still intact, so in theory, as long as they can maintain the pressures in that, and there should be relief valves on that, to maintain the pressure, even if the core was to melt, the vast majority of the radioactivity should be contained within that containment building. At Chernobyl we didn’t have that, so when the core melted and caught on fire, all the radioactivity will spread to the atmosphere and to the countryside. In this case, that should not occur, however, again we’re beyond the worst case scenario here, where the last resort now is to try to rig something up to use seawater to cool the plant and the auxiliary building, with all the safety systems has been destroyed.

21:17

Q: Well, we’ll just keep our fingers crossed and I hope that there are a lot of nuclear engineers and military people really working hard to keep this from being an even worse disaster than it is already.  Thank you very much Dad, for — Er, sorry did you want to say something?

A: Yeah, I was going to say, it’s obviously a very grave situation however, the one good thing is that Japan has many many nuclear power plants and they have a lot of nuclear experts in that country, so in addition to the help and expertise that they can get from the US and other folks that have a lot of nuclear experience they have a lot of their own people who have a lot of expertise. And I’m sure that they’re doing everything they can, but again, I do have to emphasize that I think this is an extremely serious situation.

22:10

Q: OK, thank you so much, Dad, for all of your insights.  I’m so glad I have a nuclear engineer in my family.

A: You’re welcome.

Q: I’ll get this posted, and hopefully this will answer some questions that some people have been having.

Evelyn

Evelyn is a geologist, writer, traveler, and skeptic residing in Cape Town, South Africa with frequent trips back to the US for work. She has two adorable cats; enjoys hiking, rock climbing, and kayaking; and has a very large rock collection. You can follow her on twitter @GeoEvelyn. She also writes a geology blog called Georneys.

Related Articles

34 Comments

  1. I have to say that Evelyn’s dad has no facebook, no blog and avoids the internet unless it’s for work. So for him to agree to speak out on this, means he is really concerned. Also, in the nuke industry people are trained in “safe speak”. Basically it means you use certain words that are to keep people calm, but for someone that has worked in the industry.. when you hear those words, it means AUGHAUGHAUGH!

    Let’s hope that nuke plants in Oregon and California on the coast are now reevluating where they have their diesel generators and battery capacity.

  2. Thanks to you both for the interview. It was very educational. After listenung, I now have a dumb question: if the plant is still generating steam after a shutdown, I assume the steam is still turning the turbines, so why can’t/don’t they use the electricity that they are generating to power the cooling pumps?

  3. @nwkmom: The steam is no longer controlled. It may no longer be reaching the turbines at all (conduits ruptured) or it may be reaching it with insufficient force to move the blades. The turbines themselves may be destroyed by the heat or the earthquake or both. It’s also possible that the steam we see is not part of the power production steam cycle but from the coolant cycle (which is rather scarier).

  4. Thank you to Evelyn and Commander Mervine for the interview. It clarified much that has had me wondering and raised points I had not even considered and it was terrifically informative to hear it directly from an Engineer directly without any spin. My own impression from Cmdr Mervine’s tone was “this man is gravely concerned”.

    @nwkmom: my own guess would be that the protection systems in the plant have locked out much of the control functionality seeing as there is limited power available to run the instrumentation.

  5. You don’t need to upload onto Youtube, since the file is easily accessible through Quick Time here. Someone will soon get off hir ass to provide a textual transcription.

    I’m not concerned about the nuclear power plant: the World can come together to contribute coolant (e.g. seawater) for the plant; not to mention, like your Father said, there are so many experts available in Japan to help solve this problem. Such experts don’t have to even be from Japan or Japanese in descent, considering the possibilities afforded by current technology.

    Not only do experts EXIST, but I trust the set of people concerned about the nuclear power plant coolant and the set of experts and other people who can provide enough coolant to prevent more disaster coincide in more than one individual.

    If not, Japanese radiation cannot affect the entire planet. It just may be a “zannen” situation, as it were.

    The amount of cold seawater IS limited, yes, but that just ties into global warming. Maybe Earth is becoming a hotter planet – life will evolve to accommodate for the climate.

  6. I did my best to transcribe the interview. It’s far from perfect, but I’m pretty sure I at least hit the highlights of what he was trying to get across.

    [Intro, explanation of experience with nuclear power]

    My first question is really basic, but what is a nuclear power plant?

    The vast majority of power plants in the world generate power by making steam, which powers a turbine, which is attached to a generator which generates electricity. Through transformers, attached to the electrical power grid.

    Nuclear power plants are similar but the difference is that it generates hot water or steam by the fissioning of uranium. There’s two major types of nuclear power plants in the western world. One is a pressurized water reactor where the water’s kept at a high pressure and doesn’t boil. there’s a heat exchanger on the other side of the heat exchanger the water is allowed to boil which generates steam. The other kind the water is allowed to boil and that generates steam directly to power the turbine.

    So one of the main problems they’re having in Japan is that they’re not able to cool the power plant. Can you explain why it needs to be cooled?

    Absolutely, what happened to the nuclear power plant is that the atoms fission or split in half and that generates heat, There are also materials that are created that continue to decay and that also generates heat so for some period of time after you shut down the plant you have to continue to cool the reactor core. To begin with it was very warm because you had hot water under a lot of pressure or steam and it needs to be cooled down and because of the decay of these materials and the fuel they continue to generate heat for some period of time until the decay slows down

    So they’ve shut down the plant in Japan and they’re just trying to cool it?

    Okay if you’re talking specifics the plant that we’re aware of that is in the most difficulty right now the fukushima plant unit one, it’s a boiling reactor, it achieved criticality in 1970, similar to plants in New England. That plant was automatically shut down when the earthquake occurred and for the first hour they ran on a diesel generator. Once a plant shuts down it has two ways to get power, one is from the grid and another is from generators they have on site. In this case they were operating on generators and everything was functioning as it should be. Based on news reports about an hour after the eartquake the tsunami hit and flooded the plant where the diesel generators were and caused them to lose that power and reduced them to their battery backup power only .

    And that wasn’t enough to have the cooling capability that they needed?

    The emergency backup on the batteries is very limited so they were Having a difficult time keeping the plant cool

    Did they have to go to a smaller cooling system, smaller pumps that can be run off of the battery?

    I don’t know the specifics of that plant and what they might have done in Japan, Japan being an earthquake zone probably had additional requirements that we wouldn’t have to have in other places in the world. In any event based on news reports they did have some kind of cooling capability based on battery power but they were only good for a few hours

    Yeah and the news reports said that the Japanese military were trying to get in replacement batteries to cool the plant, I’m sure they continued that effort but I haven’t found any reports in the news

    The reports that I found said exactly that, they were trying to supply the plant with batteries and diesel generators

    So how are power plants in general built to withstand earthquakes and tsunamis? You’ve worked on plants that are in more stable regions, are there requirements for natural disasters?

    There are, and depending on what the worst case scenario would be anticipated for an earthquake, the requirements are different so the best example I could give is I once participated in an inspection of the plant in Oregon, it has been shut down now but compared to plants in Wisconsin and Vermont there were a lot more requirements for earthquake protection. So the way you do that is a lot more supports for all the equipment, hydraulic dampeners which allow it to move back and forth without breaking. In Japan all the plants must be built on bedrock, so yeah there are numerous precautions and probably addition backups for the Japanese plants.

    Yeah but this was just such an enormous earthquake, I don’t think they’re released the official report yet but it’s probably in top five biggest earthquakes so even if they prepared for the absolute worst, this probably stressed their systems

    I think they key here is not the earthquake, by all reports the plant functioned exactly as they were supposed to do in the earthquake, it shut down automatically, the grid was locked and their diesel generators started. What really led to the situation was the tsunami.

    What happened with the explosion that happened earlier today, do you know anything about that?

    Well I can only comment on what I’ve read in news reports and a little bit of speculation based on my knowledge. So again this was a boiling water reactor so when its operating normally the reactor is full of water to a certain point and above that, steam, and that steam goes through pipes, turns the turbine, is cooled and returns to the reactor. Because they’re on very limited backup power, able to get only a small percentage of the water that they would normally be able to pump into the reactor to cool it they were probably allowing the water to boil which you wouldn’t normally allow during the shut down but by allowing the water to boil you’re taking heat away from the reactor and allowing it to cool. Because of the lack of power, they wouldn’t be able to use their normal and back up system to remove the steam and cool it and return to the reactor so they were probably trying to vent the steam into the buildings at the plants. Vent the steam add some cool water and keep the reactor cool enough to keep it from melting down.

    I see, and I guess the big question that everyone has is has the explosion or any of the damage, I guess there hasn’t been a lot of damage to the plant it’s just overheating, do you think any of this is causing nuclear leakage and if so is that a big problem?

    I ‘ve actually looked at before and after picture from the explosion that’s available on the news and my opinion they have an extremely serious situation at this nuclear power plant. My speculation is that they were venting the steam to try and cool the reactor, but without power they don’t have a lott of their instrumentation-

    So they can’t monitor things to the same degree

    -they don’t even have their backup power, they have the bare minimum of instrumentation provided by whatever battery power they have left. My guess is, and it was reported in the news that they had a hydrogen explosion, so they obviously had hydrogen and other gases that were generated that built up to an explosive level and if you look at the photos the entire building surrounding the reactor, the only thing left is the steel frame, the whole thing collapsed. That would normally be the auxiliary building ,and that building houses a lot of the emergency systems for the reactor. So I think we have a very serious situation at this power plant where the netire aux building has been destroyed.

    According to reports, containment is intact, if there has been any release of radioactive power it has been very minor to this point but they have got to find a way to get some electricity and cool that reactor and the last report I saw was that their plan was to use seawater, get some temporary pumps and use seawater mixed with boron.

    Boron is a substance that will absorb neutrons, very similar to borax that you wash your clothes with, that will keep the reactor from going critical again when they add the cold seawater. Even though the control rods have been fully inserted, (I think that’s what he said?) cold water is denser than warm water and can cause neutrons that are still bouncing around to moderate (slow down) so that they could strike the fuel and cause fission.

    We don’t want any more fission because that causes heat and we certainly don’ want it to go critical because that generates a lot of heat. Critical is not the bad word you see in the news, when it operates it’s normally critical, it just means it’s a self sustaining reaction. What we wouldn’t want it to do is to go to a terminology called super critical, that would be really bad. In any event, when you add the cold water and you don’t add the boron, you have the potential of causing the fission to go up and causing more heat. This is beyond the last resort to do this at a plant.

    They’re basically down to their last option.

    So what is the best case scenario, and what is the worst case??

    The best case is that he military gets generators onsite with emergency pumps and cools the reactor, they’ll have to cool it for several days. Obviously the plant is destroyed and I’m sure it will have to be decommissioned. The question is how much additional damage is there on the site, there are actually six at the site and two more that were under construction, this is just one of six reactors at that site in commercial operation.

    Oh that’s scary, so there could be trouble with the other ones?

    The question is, has this explosion – has any damage occurred in adjacent reactors and also what is the situation of the additional reactors.

    If they don’t cool them it seems like the same thing would happen to them

    It seems like a couple of them were shut down for maintenance so they’re probably less problematic because their cores would have cooled down but the ones that were operating could all be a concern.

    So do you think nuclear power plants should be built in an earthquake prone region like japan?

    I think it’s important for the nuclear industry to be unemotional about what happened here It seems like all the design features required for the earthquake functioned and the plant was going through a normal shutdown sequence. When the tsunami came that was not designed for it flooded the generators and caused a scenario well beyond any design contingencies for that plant. The nuclear industry has to take a serious look at what has occurred in Japan. Although nuclear power is an important source of electricity we have to seriously question any plants located next to the ocean and worst case scenario for this type of event, the impact it would have on that plant and the emergency backup, In this case that wasn’t taken into account and as a result we have a plant that is very very close to a core meltdown.

    And what would a core meltdown lead to? I mean is this going to contained, is there any chance this could be like Chernobyl? I know this is a different situation but is there any potential for a large radiation leak here?

    The first thing is, this is a different scenario. Chernobyl was a different type of design that was a graphite moderated reactor and probably the big difference between this and the pressurized and boiling water reactor is that a water cooled reactor is what we call inherently safe. It’s not good if the core would not be cooled, but as the water levels drop and you generate steam, the steam is less dense than the water so there’s less molecules to moderate or control the neutrons so the steam causes the power level to drop in that vicinity.

    The problem is that you have to cool because of the heat but it’s inherently stable as opposed to the Chernobyl reactor which is inherently unstable. The other big difference is that all western reactors have to have a containment building, although the auxiliary building has been destroyed, the containment building with steel liner is still intact so in theory as long as they can maintain the pressures and there should be relief valves, even if the core was to melt , the vast majority of the radiation should be contained. At Chernobyl we didn’t have that so when the core melted and caught on fire, all the radioactivity spread into the countryside. In this case that should not occur but again we’re beyond the worst case scenario, the last resort now is to rig something up with sea water to cool the plant and the auxiliary building with all the safety systems have been destroyed

    Well we’ll just keep our fingers crossed and hope there are a lot of nuclear engineers and military people working hard to keep this from being an even worse disaster

    Its obviously a very grave situation but the one good thing is that Japan has many nuclear power plants and a lot of nuclear experts so in addition to the help and expertise that they can get from the US and other folk with a lot of experience they have a lot of their own people with a lot of expertise. I’m sure that they’re doing everything they can but I do want to emphasize that I think this is an extremely serious situation

    [Thanks and goodbyes]

  7. Turbines are quite delicate and must be very precisely balanced. The vibration of the earth quake might have screwed them up enough that they tripped.

    To operate the turbine you need a steam source and a steam sink. Usually turbines are set up with multiple steam sources and different pressures with multiple steam sinks, some of them going back to the boiler to be reheated. Turbines don’t have that big a turn-down range. You can’t run a turbine at 5% power, you have to run it ~50 to 105% power. The ultimate steam sink is the condenser that uses cooling water pumped from the ocean.

    I have heard reports of steam powered coolant pumps being operated. Those probably don’t need a condenser to operate.

    The reports I have seen say the explosion was in the turbine hall. Usually the generators that are run by the turbines are cooled with hydrogen. It may have been that hydrogen that leaked and exploded and not any hydrogen having to do with the reactor.

    If the reactor vessel stays intact, the amount of leaked radiation will be small.

  8. Ashlyn — also, thanks for the transcript! I hope you don’t mind that I’ve gone through the first 8 minutes (I’ll do the rest later, hopefully) and made it match the audio more closely. You got all the substantive points perfectly, though!

    ——–
    Q: So, my first question for you is really basic, since maybe people are not familiar with this, but what, can you just describe quickly, what is a nuclear power plant?

    A: Yes I can, maybe what I’ll do first is explain what a power plant is.

    Q:Sure.

    The vast majority of power plants in the world generate steam, by some method, some by burning oil, some by burning coal, and heat up water, and make steam, that steam then powers a turbine, and attached to the turbine, you have a generator, and that generator generates electricy, and through transformers is connected to the electrical power grid.

    So, in that respect, a nuclear power plant is a lot like other power plants, in that you have this turbine, that’s steam driven, with a generator, that’s attached to a transformer and then to the grid. The difference is, what a nuclear power plant does, is it generates, depending on the type of the plant, hot water or steam, by the fissioning of uranium.

    Q: Right. And that’s providing the power, basically.

    A: So, there’s two major types of nuclear power plants in the Western world. One is a pressurized water reactor where the water’s kept at high pressure and doesn’t boil; an there’s a heat exchanger, and on the other side of the heat exchanger, that water is allowed to boil which generates steam. And then you have a boiling water reactor, where the water in the reactor actually boils and generates steam directly, and that steam is used to power the turbine.

    Q: So, another question I have for you, one of the main problems they’re having in Japan is that they’re not able to cool the power plant. So, can you explain why a nuclear power plant needs to be cooled?

    A: Absolutely, so what happenens in a nuclear power plant is that the atoms fission or split in half and that generates heat. There’s also other materials that are created (I don’t want to get into too much detail and confuse people) that continue to decay and that also generates heat. So for some period of time after you shut down a nuclear power plant you have to continue to cool the reactor core. Because you’re still, to begin with, it was very warm because you were generating hot water under a lot of pressure or steam and it needs to be cooled, obviously, down and because of the decay of these materials in the fuel they continue to generate heat for some period of time until the decay trails off.

    Q: So they’ve actually shut down the plant in Japan and they’re just trying to cool it?

    A: Okay, well if you’re talking specifics, the plant that we’re aware of that is in the most difficulty right now is the Fukushima plant, Unit One. That plant is a GE boiling water reactor, it first achieved criticality in 1970, it’s similar to a couple of other plants that we have here in New England, it’s very similar to Pilgrim, which is down in Massachucets, and Vermont Yankee, in Vermont.

    And, that plant was automatically shut down when the earthquake occurred and for about the first hour they were running on their diesel generator. Once a plant shuts down, it has two ways to get electricty , one is from the grid and another is from emergency diesel generators tgat they have on site. In this case, because of the magnitude of the earthquake, the grid basically went dark, so they were operating on their diesel generators and everything was functioning as it should be. But then, based on news reports, about an hour after the eartquake and the shutdown, the tsunami hit, and flooded the plant, where the diesel generators were, and that caused them to lose their diesel generator power and reduced them to their emergency battery backup power only.

    Q: And that wasn’t quite enough to have the cooling capability they needed?

    A: The emergency backup on the batteries gives them, you know, very very limited capabilities, so they were having a very difficult time keeping the plant cool.

    Q: Do they sort of have to go to a smaller cooling system, smaller pumps and that sort of thing, that can be run off of their battery?

    A: I don’t know the specifics of that plant and what they might have done in Japan. Obviously, Japan being in an earthquake zone probably had additional requirements for the plant that we wouldn’t have to have in other places around the world. In any event, based on news reports, they did have some type of cooling capability using their battery power but the problem of course is, the batteries are only good for a few hours.

    Q: Yeah and the news reports said that the Japanese military was actually trying to get in replacement batteries to cool the plant, I’m sure they’ve continued that effort but I haven’t heard any update on that in the news.

    A: So, the reports that I saw on the news said exactly that, they were trying to supply the plant with additional batteries and a portable diesel generator.

    Up to 7:51

  9. @jessew: Thank you! And thank you to the first transcriber as well.

    I’m a busy grad student (working in lab now), so I don’t have time to transcribe. When you finish the transcript I’ll add it to the post.

  10. Thanks so much to Commander Mervine, Evelyn, Ashlyn, Jessew and all of the skepchicks for providing this amazing information in this outstanding environment. You all rock.

  11. I saw a comment by “US nuclear experts” (AFP), that using sea water is such a departure from SOP that it “is an “act of desperation” that may foreshadow a Chernobyl-like disaster”.

    In a word, NFW!

    In Chernobyl the core was vaporized with no containment building and was not even contained within a reactor. What “exploded” in Chernobyl was the fuel vaporizing (yes, the UO2 fuel). The reactor went “hypercritical”. There are estimates that the power level went to hundreds of times normal maximum (yes, hundreds of times, in a hypercritical state the only thing that limits the power is “disassembly”. What wasn’t promptly vaporized was left in a white-hot mass of burning carbon which vaporized a lot more. Chernobyl wasn’t a “melt-down”, it was a vaporize-up.

    In thinking more about it, sea water might be the best thing to use if there is some fuel damage. Sea water contains calcium sulfate and calcium bicarbonate. When sea water is heated, it forms what is called “scale”. These are deposits of calcium carbonate and calcium sulfate that plate out on the surfaces that are the hottest. In a reactor that is overheating, that would be on the hottest bits of fuel.

    If there is fuel that has been “damaged”, what would be damaged is the outer zirconium cladding. The actual fuel is UO2 ceramic and is much more resistant to damage than is the zirconium. The usual failure mode for zirconium (and what I think happened here) is oxidation. That converts the zirconium to zirconium oxide which causes it to swell and break apart. It is mostly cracks that form and allow the fission products that are trapped inside to leak out. If those cracks could be sealed (with scale from sea water), the leakage of fission products would go down.

    If the reactor was not completely shut down (no fission going on), you would never put sea water in it because the neutrons would activate components of sea water and make it very radioactive.

    Sea water also has anions and cations which can better trap fission products than the super pure water they normally use. That is trap them so they don’t go into the atmosphere. The really bad actor is iodine. Sea water does have iodine in it

    When the reactor is shut down, all the fissioning stops, but the decay heat of the fission products continues as they decay. At shut down, that fission product energy is ~7% of the total reactor power. That decays quite rapidly. After ~100 seconds it is down about half, after 2,000 seconds it is down by half again. We are now at ~1.5 x 10^5 seconds so the power is now down to about 0.5%. That means if it was a 1,000 MW power plant, it is about 3,000 MW thermal and would now be putting out 15 MW of heat. That is still a lot of heat, it is enough to vaporize 23 tonnes of water per hour. If you want to cool it without vaporizing any water you need ~10x more flow.

    If there has been fuel damage, you wouldn’t want to let the water vaporize and release that steam into the atmosphere because that would let iodine vaporize too. But if you have to, it is better to let some iodine release than to let more fuel over heat. If the wind is going out to sea there wouldn’t be much harm.

  12. I think this interview is why Scepticism is so important.

    Fossil fuels have been vilified, and rightly so, but you ask the important questions about nuclear power in this specific instance.

    Whatever the advantages of nuclear power over fossil fuel power there might be, you haven’t shied away from asking questions about how safety should and could be improved.

    Thank you, I’ve learned a lot from your interview.

  13. Hello,

    I’m an American expat living in Tokyo for almost 10 years now. I just joined Skepchick after hearing all about it from the skeptic podcasts that I listen too. I want to thank Evelyn and her father for giving the most information about the reactor that I’ve been able to find in English since Friday. I’m sure that if I had time to scour though the internet I could have found something about it, but this helped learn just how serious the situation is and what is or should be done.

    Friday was some scary shit. However, my neighborhood never lost electricity. We have water, gas and internet coverage. I didn’t have cell phone reception for a few hours after the quake, but it seems fine now.

    I was at home. My dog was freaking out during the quake and I don’t blame him. Skeptic observation: he only freaked out after the the shaking started. I live in a relatively new condo, but I did not know what to do. There was some kind of announcement that was played on the complex’s P.A. system, but I don’t understand Japanese well enough to know if I was supposed to evacuate the building and I wasn’t about to go out to my balcony to see what the other tennets were doing.

    Most quakes that I’ve experienced here in Japan will last a maximum of 2 minutes, most far less. 45 minutes after it started, the floor stopped shaking enough that I could walk across the hall without falling down like a guy on a three day drunk. Another 45 minutes and I was able to take the dog out and let him have his nervous breakdown pee and finally pick up my 6 year old son from daycare.

    He was under the table with all the other kids wearing a special form rubber helmet. The teachers and care-givers were projecting an air of confidence for the kids and I really want to thank them for all that they did during that time.

    Allen, my son, wasn’t scared. He was angry that he couldn’t play and had to stay under the table for most of the afternoon. Nice to be young enough that those would be the only problems.

  14. Comment Part 2

    A Tokyo Fire Department Rescue station is literally next door to my condo. I know that these guys have been working non-stop since the quake occurred and I hope that they have the strength to continue with their important work. Interestingly, I only heard the truck go out, sirens blaring, once on Friday.

    Like I said, my neighborhood remains basically intact. I saw a few broken bricks on the street, a collapsed wall from a building next to Allen’s daycare and some broken ceramic tiles around my condo, but that is all physical damage I’ve seen. I haven’t gone anywhere except for a few blocks in any direction.

    However, I’m getting worried. The trains have stopped, which means freight and cargo can’t make it to warehouses and so there is nothing to load for the delivery trucks. The local supermarket and 7-11 stores haven’t been restocked in days. I hope they can get some stuff in soon because the refrigerator and cupboards are getting pretty sparse.

    I have a request for anyone that has bothered to read this far. I’m busy with a family and trying to find a way to get groceries so I can’t make the time get the information I want/need, in English. If you what you consider reliable information about relief efforts, the trains (which may be running now for all I know) etc. – the kind of information that you would need if the infrastructure in your community broke down – could you post them here as a follow-up. I would greatly appreciate any help with this.

    Thanks,

    Mark

  15. OK, here’s the final, full transcript. I understood the interview better for having gone over it so carefully (and repeatedly…) Thanks again to Ashlyn for the first version, and thanks to Evelyn for the encouragement to finish it. I left out the greetings and goodbyes right at the beginning and end, but included the description of Commander Mervine’s qualifications that wasn’t in Ashlyn’s version.

    ————

    Q: Are you ready for the interview?

    A: I’m ready.

    Q: Alright. I was hoping that we could start out, I know who you are, since you’re my dad, but if you could just introduce yourself quickly and describe some of your background in nuclear power.

    A: Sure, my name is Mark Mervine. I graduated from the US Naval Academy in 1981, and went into the Navy nuclear power program. I was in submarines, and while I was in the Navy I qualified on two different types of Navy nuclear power plants and served as an instructor in the Navy nuclear power program.

    Q: OK, and then after you got out of the Navy?

    A: After seven years of active duty, I went into the Reserves, and I stayed in the Reserves and I retired as a commander in the Navy Reserves. I went to work, initially, for Wisconsin Electric, which at that time had a 2-unit Westinghouse pressurized-water reactor in Turbridge, Wisconsin. While I was there, I completed my SRO certification, which allowed me to do senior review and oversight, as a member of the plant management staff. And I also qualified and served as a shift technical advisor, which is a position that was added in the nuclear power industry, after Three Mile Island, that is a degreed engineer position, that’s available to the on-shift crew on a 24-hour basis. Some plants do it on an 8 hour watch, at that time, Wisconsin Electric did it on a 24 hour watch, so I would actually stay at the plant for 24 hours; we had a place where we could sleep, and my job was to advise the crew whenever they needed advice on what was happening with the plant.

    After a few years at Wisconsin Electric, I went to work for Vermont Yankee, where I also completed the SRO certification, Senior Reactor Certification, which allowed me to do senior level reviews as a member of the plant management staff, and I also served on the Outside Review Committee, which is a very high-level committee for the main Yankee nuclear plant, until it closed, and also Vermont Yankee.

    Q: Excellent. So, you’re qualified to talk a little bit about nuclear power, it sounds like.

    A: I can talk a little about nuclear power, yes.

    Q: OK, excellent. So, my first question for you is really basic, since maybe people are not familiar with this, but what, can you just describe quickly, what is a nuclear power plant?

    A: Yes I can, maybe what I’ll do first is explain what a power plant is.

    Q: Sure.

    The vast majority of power plants in the world generate steam, by some method, some by burning oil, some by burning coal, and heat up water, and make steam, that steam then powers a turbine, and attached to the turbine, you have a generator, and that generator generates electricity, and through transformers is connected to the electrical power grid.

    So, in that respect, a nuclear power plant is a lot like other power plants, in that you have this turbine, that’s steam driven, with a generator, that’s attached to a transformer and then to the grid. The difference is, what a nuclear power plant does, is it generates, depending on the type of the plant, hot water or steam, by the fissioning of uranium.

    3:30

    Q: Right. And that’s providing the power, basically.

    A: So, there’s two major types of nuclear power plants in the Western world. One is a pressurized water reactor where the water’s kept at high pressure and doesn’t boil; an there’s a heat exchanger, and on the other side of the heat exchanger, that water is allowed to boil which generates the steam. And then you have a boiling water reactor, where the water in the reactor actually boils and generates steam directly, and that steam is used to power the turbine.

    4:07

    Q: So, another question I have for you, is one of the main problems they’re having in Japan is that they’re not able to cool the power plant. So, can you explain why a nuclear power plant needs to be cooled?

    A: Absolutely, so what happens in a nuclear power plant is that the atoms fission or split in half and that generates heat. There’s also other materials that are created (I don’t want to get into too much detail and confuse people) that continue to decay and that also generates heat. So for some period of time after you shut down a nuclear power plant you have to continue to cool the reactor core. Because you’re still, I mean, to begin with, it was very warm because you were generating hot water under a lot of pressure or steam and it needs to be cooled, obviously, down and because of the decay of these materials in the fuel they also continue to generate heat for some period of time until the decay trails off.

    5:13

    Q: So they’ve actually shut down the plant in Japan and they’re just trying to cool it?

    A: Okay, well if you’re talking specifics, the plant that we’re aware of that is in the most difficulty right now is the Fukushima plant, Unit One. That plant is a General Electric boiling water reactor, it first achieved criticality in 1970, it’s similar to a couple of other plants that we have here in New England. It’s very similar to Pilgrim, which is down in Massachusetts, and Vermont Yankee, in Vermont.

    And, that plant was automatically shut down, when the earthquake occurred, and for about the first hour, they were running on their diesel generator. Once a plant shuts down, it has two ways to get electricity, one is from the grid, and another is from emergency diesel generators that they have on site. In this case, because of the magnitude of the earthquake, the grid basically went dark, so they were operating on their diesel generators and everything was functioning as it should be. But then, based on news reports, about an hour after the earthquake and the shutdown, the tsunami hit, and flooded the plant, where the diesel generators were, and that caused them to lose their diesel generator power and reduced them to their emergency battery backup power only.

    6:42

    Q: And that wasn’t quite enough to have the cooling capability that they needed?

    A: The emergency backup on the batteries gives them, you know, very very limited capabilities, so they were having a very difficult time keeping the plant cool.

    6:59

    Q: Do they sort of have to go to a smaller cooling system, smaller pumps and that sort of thing, that can be run off of their battery?

    A: I don’t know the specifics of that plant and what they might have done in Japan. Obviously, Japan being in an earthquake zone probably had additional requirements for the plant that we wouldn’t have to have in other places around the world. But, in any event, based on news reports, they did have some type of cooling capability using their battery power, the problem of course is, the batteries are only good for a few hours.

    7:32

    Q: Yeah, the news reports said that the Japanese military was actually trying to get in replacement batteries to cool the plant, I’m sure they’ve continued that effort but I haven’t heard any update on that in the news.

    A: So, the reports that I saw on the news said exactly that, they were trying to supply the plant with additional batteries and a portable diesel generator.

    7:52

    Q: Right, I hope they’re successful soon. So how are nuclear power plants in general built to withstand earthquakes and tsunamis? You may not know about this, since you work on power plants that are in more tectonically stable regions, but are there some specific requirements for natural disasters?

    A: There are, and depending on what the worst case scenario would be anticipated for an earthquake, their requirements are different. So probably the best example I could give is, I once participated in an inspection of the Trojan nuclear power plant which was in Oregon. That plant has been shut down now, but compared to the plants that I had worked in Wisconsin and in Vermont they had a lot more requirements on them for earthquake protection. So the way you do that, there is a lot more supports for all the equipment, all kinds of hydraulic dampeners which allow the equipment to move back and forth without breaking. I know in Japan they have a requirement that all the plants have to be built on bedrock, so, they actually have to go down to bedrock in order to begin to build the supports of the plant. So, yeah, there’s numerous precautions that are taken and, like I said, there were probably additional backup system requirements that were required by the Japanese government, for those plants, being in an earthquake zone.

    9:22

    Q: Yeah but this was just such an enormous earthquake, I mean, I don’t think they’re released the official report yet, but this is probably in top five biggest earthquakes so even if they prepared for the absolute worst, this is something that really stressed all of their systems and backups, I imagine.

    A: Well, I think really the key here was not so much the earthquake. By all reports, the plants functioned exactly as they were supposed to do in the earthquake, they shut down automatically, when the grid was lost their diesel generators started, and everything was fine. What really put us in the situation we’re in now is the tsunami as a result of the earthquake, but not the earthquake itself.

    9:58

    Q: So, what happened with the explosion that happened earlier today, do you know anything about that?

    A: Well I can only comment on what I’ve read in news reports and a little bit of speculation based on my knowledge of how nuclear power plants work.

    So again, in this case, this is a boiling water reactor, so when its operating, normally the reactor is full of water to a certain point, and then above that, steam, so the core is kept covered in water, but above that steam is generated, and that steam goes through pipes, normally, turns the turbine, and then is cooled and returned back to the reactor.

    Because they’re on a very limited backup capability, only to get, probably, a small percentage of the water that they would normally be able to pump into the reactor to cool it, they were probably allowing the water to boil, which you wouldn’t do normally, during a shut down. But by allowing the water to boil you’re taking heat away from the reactor and thereby cooling it.

    Because of the lack of power, they wouldn’t be able to use their normal and back up systems to remove the steam and cool it and return it to the reactor, because there was no power. So they were probably trying to vent this steam into the buildings at the plant. If they could vent a little bit of steam, add a little bit of cool water, they could keep the reactor cool enough to keep it from melting down.

    11:34

    Q: I see, and I guess the big question that everyone has today is, has the explosion or any of the damage, I guess there hasn’t been a lot of damage to the plant, it’s just overheating, do you think any of this is causing nuclear leakage and if so, is that a big problem?

    A: So, I‘ve actually looked at the before and after picture from the explosion that’s available on the news and, in my opinion, they have an extremely serious situation at this nuclear power plant. So, my speculation is they were venting the steam in order to try and cool the reactor, unfortunately, without power they don’t have a lot of their normal instrumentation that they would have.

    Q: So they can’t monitor things to the same degree —

    A: They don’t even have their backup power, I mean they basically have the bare minimum of instrumentation provided by whatever battery power they have left. My guess is, and it was reported in the news that they had a hydrogen explosion, so they obviously had hydrogen and other gases that were generated, that built up to an explosive level and if you look at the photos the entire building surrounding the reactor, the only thing left of it is the steel frame, the whole building has collapsed. That would normally be called the auxiliary building, and that building actually does house a lot of the emergency systems for the reactor. So I think we have a very very serious situation at this power plant where the entire auxiliary building has been destroyed.

    According to reports, the containment is intact, so if there has been any release of radioactivity, it has been very minor, to this point, but they have got to find a way to get some electricity, and cool that reactor. And the last report I saw said that there plan was to use seawater. So obviously, they’re going to get some temporary pumps, they’re going to use seawater, mixed with boron. Boron is a substance that will absorb neutrons, very similar to borax that you could go buy to wash your clothes with, that will keep the reactor from going critical again when they add the cold seawater. Even though the control rods have been fully inserted, when you add cold water, cold water is denser than warm water, and it can cause the neutrons that are still bouncing around the reactor to moderate, to a speed at which, (so moderate means slow down), they could strike the fuel and cause a fission.

    We obviously don’t want any more fission because that generates more heat and we certainly don’t want the reactor to go critical because that generates a lot of heat. And, critical is not the bad word that you see in the news, where you say “Oh, reactor’s going critical!”; when it operates, it’s normally critical; all critical means is it has a self sustaining reaction, which is what you need to operate. What we wouldn’t want it to do is to go to a terminology called super-critical, that would be really bad. But in any event, when you add the cold water and you don’t add the boron, then you have the potential of causing the fission level to go up in the reactor and more heat to be generated, which you don’t want to do. This is beyond the last resort, to do this, at a nuclear plant.

    Q: To use sea water to cool it —

    A: I think they’re basically down to their last option here.

    15:10

    Q: So what do you think is the best case scenario for this plant, and added to that question, what is the worst case scenario?

    A: I think the best case is that the military get the generators on-site with some emergency pumps and they’re able to rig up a cooling system to cool that reactor, to keep it cool, and they’ll have to cool it for several days before it gets to the point where the heat is decayed off. Obviously the plant is destroyed, and I’m sure it will have to be decommissioned. The question is how much additional damage is there at the site, because, there’s actually six nuclear reactors at that same site and two more that were planned or are under construction.

    15:56

    Q: I see, so this is just one that’s been failing.

    A: This is just one of six reactors at that site that were in commercial operation.

    16:08

    Q: Oh that’s scary, so that there could be trouble with the other ones.

    A: The question is, as a result of this explosion – has any damage occurred in any of the other, adjacent, reactors and also what is the situation of the additional reactors?

    16:26

    Q: Right, if they don’t cool them, it seems like this same thing could happen to them.

    A: They would have the same problem, so a couple of the plants were shut down for maintenance so they’re probably less problematic because their cores would have cooled down but the ones that were operating at the time that the earthquake occurred, could all be a concern.

    16:51

    Q: So I guess a final question I have for you is, do you think nuclear power plants should be built in an earthquake prone area such as Japan?

    A: I think it’s important for the nuclear industry, to be unemotional about what has happened here. So, like I said, it does appear that all of the design features that were required for the earthquake, functioned, and the plant was going through a normal shutdown sequence. Obviously, when the tsunami came, that was something that was not designed for, because it flooded the location where the emergency diesel generators were and caused them to lose all power, and we’re now in a scenario that’s well beyond any design contingencies that were designed for that plant.

    So, I think the nuclear industry has to take a serious look at what has occurred in Japan. Although nuclear power is an important source of electricity, I think we have to seriously question any plants that are located next to the ocean and the worst case scenario for this type of event, an earthquake followed by a tsunami, as to the impact it would have on that plant, and the emergency backup system.

    Clearly, in this case, this was not taken into account and the net result is, we have a nuclear plant that appears to be very very close to a core meltdown.

    18:32

    Q: And what would a core meltdown lead to? I mean, is this going to be contained? Is there any chance that this is going to be like a Chernobyl type situation? I mean, I know that’s a different scenario, but is there a potential for a large radiation leak here?

    A:So, you ask a good question, and probably one that is on the mind of the public. So, the first thing is, this is a different scenario from the one that happened at Chernobyl. And let me just explain a little bit. Chernobyl reactor was a completely different type of design than those that we typically have in Western society. That was a graphite moderated reactor and probably the big difference between either a pressurized water reactor or a boiling water reactor like we have in the West, is that a water cooled reactor is what we call inherently stable.

    In this boiling water reactor, even though, it’s not good that the core would not be cooled, as the water level drops, and you generate steam, the steam is less dense than the water, so that means that there’s less molecules of water to moderate or slow down the neutrons. So, when a steam void forms, it actually causes the power level to drop in that vicinity, or the heat generation to drop in that vicinity. The problem you have, of course, is you do need to cool the reactor because you have all this residual heat, but a pressurized or boiling water reactor is inherently stable, as opposed to the Chernobyl design which is inherently unstable.

    The other big difference is, all Western reactors have to have a containment building. And so, according to the news reports, although the auxiliary building has been destroyed, the containment, or steel liner, has not been destroyed. So that’s still intact, so in theory, as long as they can maintain the pressures in that, and there should be relief valves on that, to maintain the pressure, even if the core was to melt, the vast majority of the radioactivity should be contained within that containment building. At Chernobyl we didn’t have that, so when the core melted and caught on fire, all the radioactivity will spread to the atmosphere and to the countryside. In this case, that should not occur, however, again we’re beyond the worst case scenario here, where the last resort now is to try to rig something up to use seawater to cool the plant and the auxiliary building, with all the safety systems has been destroyed.

    21:17

    Q: Well, we’ll just keep our fingers crossed and I hope that there are a lot of nuclear engineers and military people really working hard to keep this from being an even worse disaster than it is already. Thank you very much Dad, for — Er, sorry did you want to say something?

    A: Yeah, I was going to say, it’s obviously a very grave situation however, the one good thing is that Japan has many many nuclear power plants and they have a lot of nuclear experts in that country, so in addition to the help and expertise that they can get from the US and other folks that have a lot of nuclear experience they have a lot of their own people who have a lot of expertise. And I’m sure that they’re doing everything they can, but again, I do have to emphasize that I think this is an extremely serious situation.

    22:10

    Q: OK, thank you so much, Dad, for all of your insights. I’m so glad I have a nuclear engineer in my family.

    A: You’re welcome.

    Q: I’ll get this posted, and hopefully this will answer some questions that some people have been having.

  16. A few people on the internet have mentioned that I have a high-pitched, somewhat annoying voice. Yes, I know. Sorry about that- it’s genetic.

    I hope the information still comes across clearly.

  17. I listened and it answered many things I’ve been wondering. Thank you!

    It is very easy to upload this interview to YouTube. That would make easy access to it. And you could link the video here and at your web site.

    I don’t know if you would want to do that or not. But if you do want it on YouTube and don’t know how to do it I can do it quite easily. It would just take minutes. And I’d be happy to do it. I know many people want to know more, especially more about the comparison to Chernobyl. I could put the photo of you and your dad from your web site on the video if you wanted it done.

  18. I listened and it answered many things I’ve been wondering. Thank you!

    It is very easy to upload this interview to YouTube. That would make easy access to it. And you could link the video here at your web site.

    I don’t know if you would want to do that or not. But if you do want it on YouTube and don’t know how to do it I can do it quite easily. It would just take minutes. And I’d be happy to do it. I know many people want to know more, especially more about the comparison to Chernobyl. I could put the photo of you and your dad from your web site on the video if you wanted it done.

  19. Thank you for your courage in putting your “somewhat annoying” voice out on the ‘net, in such a public situation. Hopefully, the small-minded twits who chose to complain about it will avoid any damage to their delicate sensibilities by simply reading the transcript in the future. ;-)

  20. Yes, I was actually very nervous about my voice. I *know* that it’s annoying.

    But I decided to put the interview up anyway because the information is important.

    If any real reporters with better voices would like to interview my dad, he would probably agree :-).

  21. @amino: Thank you so much, amino! This is great.

    Someone with some professional experience in video editing is currently making YouTubes of the interviews (he’s going to try to cut out some of the pauses and such), so I might upload those ones if they’re better.

    Yours is great, though!

    And all of you are proving that, despite the fact that I go to MIT, you are more technically able than me. It’s a miracle I was able to record the call at all ;-).

  22. The professional will be better. You should upload those too.

    By the way, your voice isn’t irritating.

  23. Evelyn,

    you say:

    “And all of you are proving that, despite the fact that I go to MIT, you are more technically able than me.”

    But it’s very easy to upload at YouTube. I think they’ve made it easy as they could. In fact, you can record video directly onto YouTube with a web cam. There’s an option on the “Upload” page that says “Record from webcam”. I think video is better than audio. It’s easier than you’d think to do it, and more fun than you might think.

  24. No, you’re not lazy.You’re at MIT? Then you must be busy. Not lazy, busy with important stuff.

    Thanks again for the interview with your dad.

    Nite.

  25. BTW, get your professional friend to show you how to use YouTube, will be quicker than self teaching.

  26. Speaking of annoying voices, I think mine is annoying too, but apparently others don’t. In fact, a high school classmate once got me two be the newsreader on a fake news cast he created for a class. He went on to be news director at Boston all-news radio station (maybe he learned from his mistake?) So <deep radio voice> speaking professionally, you sound fine </deep radio voice>.

    P.S. Maybe some day, when the dust has settled, you could repeat your interview live at the Boston Skeptics in the Pub? (Are you back in Cambridge? Only 2 T stops away!)

  27. Responding to kittynh, Oregon’s one plant, Trojan mentioned by Commander Mervine, is indeed decomissioned.. so we are nuke free. And many here will fight to keep it that way. You have to wonder though, if these companies are so smart to have hydraulic dampening for their plants, why site by the ocean where you can’t protect the systems from tsunamis. Yes, fission reactors use lots of water to cool down, but lakes and rivers usually suffice. I worry about the folks south of us by San Onofre. My father in law was a geologist in the Navy and tried hard to warn people they have a plant built RIGHT ON a fault line by the ocean. Perhaps Richard Heinberg is right that we (at least collectively) are a species no brighter than amoebas. Hopefully this tragic example will wake people up a bit.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Back to top button