March 16, 2011
5th Interview with My Dad, a Nuclear Engineer, about the Fukushima Daiichi Nuclear Power Plant Disaster in Japan
|Picture of a Boiling Water Reactor Nuclear Power Plant like the Fukushima Plants. My dad refers to this image in his interview.|
Update: All the interviews are now available on a vimeo channel. Here’s the vimeo channel:
Update: Sorry about the echo starting partway into the recording. Not sure how to fix– I am using Pamela Call Record to record skype-to-landline. Fortunately, my dad does most of the talking and he does not echo.
Here is the 5th interview I have conducted with my dad, a nuclear engineer. Please see the rest of the blog (sidebar) for previous interviews.
In the interview today, we address many questions from listeners. Please keep sending questions and comments to [email protected]. You can also follow me on twitter @GeoEvelyn but please do not send questions via twitter.
Link to vimeo:
EM: Good morning. My name is Evelyn Mervine and I’m going to be interviewing my dad, Mark Mervine, who is a nuclear engineer. This is the 5th in a series of interviews that we’re going to try and do on an almost daily basis, to update people about the Fukushima nuclear power plant disaster. I just want to start out, since there are going to be many interviews, by stating that the time is currently 12:40 PM Eastern Standard Time, and it is the 16th of March. Dad, I just want to start out by asking you to give another update. I know that there have been quite a few developments over the last 24 hours, yet again.
MM: So my first update is it’s actually 12:40 Eastern Daylight time—
EM. Oh. Sorry.
MM: — because we changed last weekend. So, I’ll do my best to give an update. As I spoke about yesterday, it’s extremely difficult to pull all these bits and pieces together from various different sources: from the internet, from news reports. There is still a lack of a comprehensive source that anyone can go to, and I noticed in the news yesterday evening that a lot of the reporters were echoing the same sentiments that I had yesterday, that there just isn’t enough being information provided and
there’s not enough transparency being provided, as to exactly what’s happening at the Fukushima 1 plant. So, let me tell you— to the best of my ability— what I’ve been able to pull together of the current situation.
I’m going to start with two of the Units that we haven’t talked about. So, just as a refresher, there are actually 6 nuclear power plants located at the Fukushima 1 Site. We’ve been most concerned about Units 1 through 4, and we haven’t had a lot of discussion about Units 5 and 6. 5 and 6 are a little bit newer. All of these plants were designed and built in the 60s and 70s. So they’re, by today’s standards, relatively old designs and old technology. But Units 5 and 6 are the newer of the two plants. And they’re also physically separated from Units 1 through 4. 1 through 4 are lined up adjacent to each other. 5 and 6 are adjacent to each other, but separated from 1 through 4.
So, the news report today is actually a little bit of good news. They’ve been able to restore one of the diesel generators to Unit 6, and restore some power to Unit 6. So, hopefully that means that they’ve restored enough power to provide cooling pumps to keep both the reactor and the spent fuel pool in that unit cool. And they’re also attempting to run a cable from the diesel generator of Unit 6 over to Unit 5, to supply power to the pumps in Unit 5. So, based on that report, I would say— at this time—
So, now we’ll turn our attention to Units 1 through 4. And, in particular, Units 3 and 4, which are the ones that have had the most activity and issues in the past 24 hours. So, based on the information that I can pull together, we’ve got serious problems with the spent fuel cooling pools in both Units 3 and 4. We talked about—I think it was just yesterday— the potential of having issues with those pools, if they weren’t covered with water and if they weren’t cooled. And I also talked about the fact that Unit 4 was in a maintenance outage and that there was a potential that the risk in the Unit 4 pool was higher than the others, because they may have offloaded the entire core in order to do more detailed maintenance of the reactor vessel or inspections.
It also looks like yesterday they had the same issue with the spent fuel pool at Unit 3. And for a period of about an hour yesterday, they had to evacuate the entire plant. So, they had already reduced the staff from about 700 to 800 people, to 50. And they had to completely evacuate the entire plant, because the radiation levels had gone quite high. And this is a speculation on my part, but based on photos and news reports, it looked like that was a result of the water in the Unit 3 spent fuel pool boiling off and releasing radioactivity into the atmosphere.
The latest, in terms of what they’re trying to do, is they’ve got to find a way to get water into those pools. They apparently are close to getting electrical power from the grid back to the station. And there’s a report that they’re trying to run basically a long extension cable into Unit 3, which would allow them to start the pumps and pump water into the spent fuel pool. They also have
attempted— and I don’t think they’ve been successful— to drop water from helicopters. And they’re also bringing in a police water cannon— that would be normally used for riot and crowd control— to use that and see if they can shoot water into these two reactor buildings.
EM: May I ask a quick question, Dad? So, are they basically using these strategies—helicopters and the police cannon— because they’re unable to get any personnel close enough to run the pumps, because of high radioactivity levels?
MM: That’s what has been reported and that would be my best guess as well. Because of the radiation levels, it’s extremely difficult, if not impossible, to get people close enough to the pools now to use, say, a normal fire hose or run a regular pump or something like that. So, you’ve got to do something to be able to get enough water in there to get the radiation levels down. As I mentioned yesterday, water does two things: it cools, and it’s also a good shield of radiation. So, if we can get enough water back into those pools, it’ll form enough of a radiation shield to lower the radiation levels, which then hopefully allow people to get close and restore [normal] cooling or use fire hoses or whatever we have available to get those pools completely covered again.
EM: Do you have any other suggestions on how they might get water in there? I know that you used to think about worst-case scenarios at power plants quite often. Is this a scenario that you even thought about in your previous experience?
MM: Well, as I think I’ve indicated in a couple of the first interviews, we’re well beyond the design basis of these plants and the contingencies for which the systems were designed for. And the problem is— which you picked up on, based on your question— is now we’ve reached a point where the radiation levels are so high, we can’tactually get people close enough. I mean, the first thing that you would’ve done, had you noticed the water levels were dropping, was maybe gotten a fire hose up there and just poured water into the pool. Somehow, in the midst of all of the chaos, they apparently were not keeping a close eye on that; they missed that opportunity. Now they’ve got a bigger crisis on their hands and somehow, someway, they’ve got to get enough water there to knock down those radiation levels. And it sounds as if they’re trying to get power, which will allow them to restore pumps, and they’re trying helicopters, water cannons, whatever they can. And the reason why you can’t run up there with a fire hose is, again, the radiation levels. So, hopefully with the water cannons they can be far enough away to be at a safe distance to shoot that water.
EM: I’m going to ask a question that I asked yesterday, and perhaps the answer has changed in the last 24 hours. Many people are concerned if they live in Japan or if they live nearby —- even if they live in the Pacific or the West Coast of the US. Now that the situation has changed and there is clearly more radiation, would you change your earlier statement about [recommendations for] people leaving Japan or Tokyo? Also, do you think they should increase that evacuation perimeter around the nuclear power plants?
MM: So, my first response is: I think people have to follow the direction of the authorities. I don’t have access to any real-time data as to what the radiation levels are. I will say this: I think the risk to people that are outside of this 30 kilometer [evacuation] zone is still probably fairly low. And the reason why is we have the good fortune that the winds are blowing from the east to the west. And whatever radiation is being released, most of it is being carried out over the ocean. So, if the winds change direction, and the radioactivity releases increase, then that could be problematic. But at the current time, it’s not.
EM: I’ll continue to probably ask you that question as we do these updates because I know that it’s something that is at the forefront of people’s minds, [people] who are within a close distance to this nuclear plant.
MM: Okay. Before you get into the questions for me, I wanted to talk about something that I’ve seen in the news, and I think I’ve seen a couple people ask the question and I don’t think they really got an answer. There was some heightened concern about Unit 3 because it used what is called a MOX— M-O-X, or Mixed Oxide Fuel. And I wanted to explain what that was. So, there’s a couple different ways that you come up with a mixed oxide fuel. So first off, in the fuel rods, we have uranium. But it’s really a uranium oxide that’s manufactured into a ceramic-like pellet.
EM: I may have missed this, but can you explain why it would be a bigger concern to have MOX fuel?
MM: Well, my point is I don’t think it’s that much more of a concern because all of the fuel ends up having plutonium in it.
EM: But why is plutonium more radioactive or of more of a concern?
MM: Plutonium is generally more of a concern from a human health perspective. So, the impact to the human body for plutonium exposure is worse than, say, uranium. That’s why.
EM: That answers the question. Do you have anything else that you would like to say before I go on with questions that are sent in by email or in comments?
MM: Only thing I could say is I hope this is helping people. It is definitely very difficult to pull the information together. I wish there was a more comprehensive source [of information]. I wish that the Tokyo Electric Power Company would be a little more forthcoming and, like I said, I hope this is helping people.
EM: Thanks, Dad. So, before I go on with questions, I just want to say that we’ve already answered quite a few questions from listeners, so if you haven’t done so already, check out the previous interviews. We’ve answered questions in interviews 2, 3 and 4. And now, thanks to some listeners, we actually have transcriptions, so if you don’t feel like listening to the interviews, you can read through the transcriptions to see if you question has already been answered. And I didn’t say at the beginning, but I just want to say that if you want to get more information on these interviews and the transcripts, you can find them on my geology blog, which is Georneys (georneys.blogspot.com; now at blogs.agu.org/georneys).
So, I’m going to go on now, to a question that has been sent it to me, and if we don’t answer your question, sorry. These questions are coming in and many of them. I’m doing my best to compile them, and if it’s your question and it’s not answered please send it in again.
MM: Okay. Well, I’m going to assume that this is in reference to the Unit 1, 2 and 3 reactors, which shut down automatically at the time of the earthquake. All the control rods were inserted, and they went sub-critical. And the problems that we’ve been dealing with have been due to the residual or decay heat that continues to be generated from the nuclear reactor, due to the fact that, initially, right at the time of the shutdown, the fuel was probably at about 1100 degrees. So, like your car— if you drive your car on a warm day, you can go out an hour later and the engine’s still warm. So, it takes a while, just to cool off because of that. And then also because of the continuing decay of radioactive particles in that fuel, that will generate heat as they decay, so it takes a matter of days, weeks, and months for a fuel bundle from a nuclear reactor to cool off to the point where it doesn’t need any
EM: And I know that we did explain this in our previous interviews, but can you just explain what it means for something to be critical?
MM: So, what it means for a reactor to be critical is you have to have a self-sustaining chain reaction. So, in the reactors that we’re talking about, that means that we have to generate as many neutrons as are being absorbed, because the uranium or plutonium has to absorb the neutrons in order to fission. And some of these neutrons will be lost. They’ll actually exit the reactor core. Some we know will be absorbed by uranium-238 and form plutonium, but it’s not fissioning, and some will be slowed down and fission. And so you have to generate- for every neutron that causes the fission, you have to generate about 2 ½ neutrons, because of the losses, to sustain a critical reaction, so that reactor power will remain constant.
Now, to answer this question, why can they say that the possibility of re-criticality is not zero with the reactor’s already shut down? Well, the problem is, we know that— it’s been confirmed by the company that they definitely had some fuel damage in Units 1 and 2, and by all indications, given the data that’s out there, I think that any engineer or scientist out there will tell you that also [there’s fuel damage in] Unit 3. We don’t know the extent of that damage. They’ve said that as much as 70% of the fuel may be damaged in Unit 1. But we don’t know the extent of that damage— is it [the fuel] blistered, is it warped? Has it melted? If it melts, it loses its form.
EM: So, what would happen if it did go critical? Since there have been reports that containment has been damaged?
EM: Do you know if— now that they’re having to use helicopters and police water cannons— they’re just using regular water? Do you think they’re putting boron in that water or are they so desperate that they’re not even putting in boron? Do you know?
MM: The reports that I saw said that they were using a mixture of water and boron.
EM: All right, I think we’ve answered that question. I’m going to move on to a second question. And I think we’ve answered this question already, but it still might be unclear for people, so perhaps you can briefly address it again. The question is: “I have a question about the hydrogen explosion. Why didn’t they let the hydrogen out before it exploded?”
MM: Well, the answer to that is: they were letting it out. They were letting it out of the reactor, and they were letting it out of the primary containment, to keep the reactor vessel and the primary containment from exploding. The secondary containment is not a completely air-tight, sealed concrete enclosure. It’s, as you can see from some of the pictures, it’s kind of a typical industrial building with a metal skeleton and it can be either concrete or, in some cases, they’ll use metal for the walls. Not much different from a typical factory building.
EM: Okay, that answers the question. We’ll move on to another question. And this is one we addressed a little bit earlier. We’ll talk a little bit more about it specifically. It’s from a reader on the West Coast of the United States— many of these listeners and readers are— and this person is concerned about radiation, like many people, and wants to know is there any reasonable scenario where we [here in the US] might be exposed to a significant amount of radiation from the current crisis. And are there any unreasonable scenarios? Because there’s a lot of hype about this in the mainstream media. And they also want to know: if there is going to be a possibility of major radiation exposure, how much of advance warning are they likely going to get, so they can prepare for this? The reports I’ve read, there have been frantic runs of pharmacies for potassium iodine and things like that. Can you maybe say, in your opinion, what would be a rational response, if you’re living on the West Coast of the United States?
MM: My response to that would be that I would sincerely hope that our scientists and our government and our engineers would be a lot more transparent with the American public than [they] have been in Japan. Because we’re talking about if there was a more significant release of radiation, thousands of miles that it would have to travel. A lot of it will be dispersed, because as you expand the cloud geometrically, you obviously lose the radioactivity on a volume basis. But we would have time before it would reach us. A lot of it depends on how much and which way the winds are blowing. At this point in time, there’s no concern. So, there should be no reason to panic and for people to go out and buy potassium iodine at this time. And I think that we can count on our society to be a little more transparent and open. And if a scenario developed that was a concern, we would have a day or two— because of the time it [the radiation] would take to travel— to make preparations.
EM: Okay, I think we should basically reassure people that at this station. They should remain calm, and they shouldn’t do anything. They should just pay attention to any announcements.
MM: Exactly, I don’t think there’s any reason for concern, but if something dramatically changed, I think that people would be told what they need to do, and we would have the luxury of time that the people in the island of Japan don’t, because they’re so close.
EM: Thank you, Dad. Moving on to another question— I actually really like this question: “So, imagine if your dad were to interview the top TEPCO officials or could be a reporter at a TEPCO press conference. What would his top 10 questions be? Or, to put it another way, what significant data would most clarify the reactors and the extent of the damage?”
MM: Well, first off, I would have more than 10 questions. But I think the important thing that I would ask to receive is that they need to assume that the general public is intelligent and they need to provide them with as much information as possible. I think sometimes there’s a tendency when things happen, whether it be nuclear or some other event, to filter the information, because we’re afraid of the reaction, or we’re afraid of panic. But in this case they’re at the opposite end of the spectrum— where they’re providing not enough information, very little information—that people are starting to get very upset and panic, because they feel like they’re not being provided with enough information. And I would agree with those people – not enough information is being provided. I’d need more than 10 questions for them, but the main question I would have would be: “Please tell us exactly what is happening and treat us as if we’re intelligent and give us as much information as possible.”
EM: I want to echo that very strong statement.
MM: So, you know, it’s really a hypothetical question. What I can tell you is that, again, these plants were designed and built in the 60s and 70s. The newer designed plants that are in the process of being certified or being designed have a lot more passive capability, such that you don’t need pumps, you don’t need operators. You know, this isn’t necessarily a bad idea here, but unfortunately, it doesn’t help the current situation. In fact, these plants don’t have it. They need electricity; they were designed with a defense in depth. There are multiple pumping systems—low-pressure, high-pressure, there were ones that were steam-driven and didn’t require electricity. Because of the magnitude of what occurred, the beyond-design-basis earthquake and the beyond-design-basis twosami
—tsunami, excuse me—I know a couple people have chuckled at my pronunciation. Unfortunately, all of these different layers of defense have failed and some way. They need to get water, and, some way, they need to get electricity. And at least from news reports, it sounds like they may be on the verge of getting some electricity back, which would be a huge, huge help.
EM: We’ll move to another question. Someone was wondering why the plant can’t be monitored remotely? These days, with the internet and things, you can do a lot of things remotely, and it seems like at this plant, they actually are mechanically doing everything, and this person thinks that it’d obviously be a lot safer if you could monitor a situation like this from further away rather than leave a skeleton crew. And perhaps it’s related to the fact that the plants are old and were built a long time ago. Do you think that that is why? Is this a capability that a modern plant might have?
MM: Well, it’s a good question. So, normally, there would be several hundred people that would work at these plants, and they had to reduce the staff to the bare minimum because of the concern for the radiation. So, a lot of it is being done by a skeleton crew. Relative to what remote monitoring capabilities they have, the answer is even though the plants are older— and again I can’t speak for these specific plants— but older plants were retrofitted with more modern remote monitoring capabilities. Clearly, in the 60s and 70s, the kind of computers that we have today didn’t exist. But plants do get upgraded and improved. And we have computers, called Plant Process Computers, that monitor a number of different parameters within the power plant, and those can be fed to other computers.
With that being said, there’s a lot of parameters still where technology didn’t exist at the time to do that, and so there’s probably a lot of parameters in these plants which are not available. And, often times, those would be on systems that are not needed to operate the reactor normally, so it may turn out in this case that a lot of the systems that you would need, that are secondary systems, cooling systems, that type of thing, wouldn’t have that level of monitoring associated with them anyway.
EM: Okay. So, a question that I actually thought of is: are there any concerns with remote monitoring about security? I mean clearly you don’t want someone to hack in there and be able to control a nuclear power plant. Are the securities where they do this [remote monitoring] pretty robust?
MM: So again, I can’t answer the specifics of what Tokyo Electric Power Company would have, but obviously that would be a big concern. But not just to a company that runs nuclear power plants— that would be a concern to a company that runs any kind of power plant. And it’s a concern to every company that has a network. So, everybody takes efforts in terms of firewalls and security and passwords and those types of things to protect their data.
EM: Okay. The last question that I’m going to ask today is: there have been many concerned about the spent fuel rods. I’m wondering why they couldn’t just move the rods to somewhere safer?
MM: Okay. Well, that’s also a good question. And if we had the luxury of time that would probably be a possibility. But unfortunately now, we’ve had the reactor buildings— of at least 3 of these 4 reactors that are of the most concern— significantly damaged. The up-close photos reveal even more damage than it appears from the long-distance television shots that we’ve all seen. And if you refer back to that drawing that I sent you yesterday, of the Mark 1 boiling water reactor containment, you will see in that what looks like a big crane— it’s orange in color— and attached to that is a long, black arm and then a yellow container. That crane is the crane that would be used to move the fuel from the reactor to the spent fuel pool and out of the building. With all that equipment damaged, it’s really, at this point, probably impossible to move any of that fuel.
spent fuel pool anymore for all of the fuel, so they take it out— really old ones that have already cooled down— and they put them in what’s called dry cast storage, which is a big concrete container where the rods don’t need—or, I’m sorry, the fuel bundles— don’t need any other cooling, except what they can get from air. And they’ll take those, and they’ll fill a big concrete pad with a big fence, and they’ll put these casts, and they’ll take the really old rods that have cooled for years and put them in there to create more space in the pool.
EM: Okay. Thank you very much, Dad. Those are all the questions that we’re going to answer today. We’ve tried really hard to answer as many questions as possible, and again, please do keep sending in question and comments. We’ll try and improve these interviews. Again, we’re not professional journalists, but we’re doing as best as we can with other obligations. And if for some reason I missed your question, please send it to me by email, and you can find my email ([email protected]) on my website (georneys.blogspot.com; now at blogs.agu.org/georneys). Okay, thank you very much, Dad.
MM: You’re welcome. I hope this is really helping people. I think we’ve been a little bit more aggressive today— probably, like all of you, showing a little bit more frustration towards the lack of information. There are no bad questions, so we’ll try to answer as many as we can. Keep them coming and we’ll do this as often as we can to try to keep people up to date.
EM: Okay, so I’m going go ahead and post this audio as soon as I can.