March 24, 2011
11th Interview with My Dad, a Nuclear Engineer, about the Fukushima Daiichi Nuclear Power Plant Disaster in Japan
Posted by Evelyn Mervine
Update: Gerald has kindly hosted all of the new audio files. I am still updating all the audio links (some of which are broken). I’ll try to finish this up tonight– been busy! Meanwhile, you can listen to all the audio files on the new vimeo channel Brandon and I created. You can also listen to most of the interviews on Brad Go’s YouTube channel.
Here’s the vimeo channel:
Brad Go’s YouTube channel:
This evening my dad and I recorded our 11th interview on the Fukushima nuclear power plant disaster. Please see the rest of the blog (sidebar) for previous interviews. 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.
In today’s interview:
1. My dad gives his usual update
2. We discuss:
a) radiation in Tokyo tap water
b) preparing for emergencies
c) can older nuclear power plants be retrofitted with passive cooling systems?
d) should some nuclear power plants in disaster-prone areas be shut down?
e) what happens to spent fuel rods (in the US) at decommissioned nuclear power
Here are some websites we refer to in today’s interview:
Here is a link to the audio:
Here is the interview on vimeo:
Please see the announcement page for more information about these interviews:
If you have time and interest, please transcribe this interview. Our next interview will be on Friday, March 25th. Thanks to Michelle and Dave, there is now a transcript after the jump.
Transcript for Interview 11:
Q: Hello, Dad.
Q: Are you ready for our interview?
A: I am.
Q: Can you hear me OK?
A: I can hear you.
Q: All right, let’s get started, then. My name is Evelyn Mervine and I’m going to be doing an interview with my dad, Mark Mervine, who is a nuclear engineer. This is the 11th in a series of interviews that I’ve been doing with my father about the Fukushima nuclear power plant disaster in Japan. If you wanna listen to any of the previous interviews, you can find them on my geology blog, Georneys. Which is G-E-O-R-N-E-Y-S. Georneys.blogspot.com. And because we’re doing so many of these interviews, I just wanna quickly state that the day and the time. It is currently the 24th of March and it is 8 PM, Eastern Daylight Time.
And in today’s interview, my dad is going to give his usual update about the situation in Fukushima and the last interview we did was 48 hours ago, so there will be a 48-hour update. And then I’m gonna ask my dad a few questions. So with that said, Dad, do you want to get started on your update?
A: OK, so there wasn’t a lot of information in the last couple of days, so again, it is very difficult to piece together an exact situation, but let me start with a reminder that there’s actually 6 reactors at Fukushima 1 site. And the two that have been the least damaged and the least concern are Units 5 and 6, which if you look at the photographs of the site, they’re physically separated by some distance from Units 1 through 4. And they have been able to get power back to those units. First, the diesel generators and subsequently from the grid. And both of those reactors, they’ve been able to restore normal shutdown cooling and both of those reactors are in cold shutdown.
Q: So those reactors should be safe at this point?
A: Relatively safe, but keep in mind that they’re going to continue to need power and cooling.
Q: But there is relatively little damage from the explosions or form the earthquake at those plants. Now that they have power back up, they’re pretty much functioning about normally?
A: Well, y’know, it’s not clear what the extent of the damage was, but they were the least impacted and they are in normal shutdown, cold shutdown. And I did read where when they restored the electrical power from the grid, they did have a problem with one of the pumps at one of those units, but it wasn’t clear if they had been able to fix that problem or not. But for the most part, I think they’re not of too much concern. I also read – and we’ve covered this a couple times – is that there’s actually 7 spent fuel pools. There’s one in each reactor and then a common one. And I read that they were able to get electrical power back to the cooling systems at the common one and it wasn’t clear what the status is, as to whether they were able to go and restore cooling, but they’re obviously getting close, if they haven’t. And the common pool, because it has fuel rods that are much older, that hadn’t most recently been in the reactors, hasn’t been too much of a concern, during this incident, being that it didn’t heat up as much as the other pools.
Q: What does “cold shutdown” mean exactly?
A: Cold shutdown would be cooled all the way down to less than 200 degrees. The exact definition is going to vary by the design of the plant, but you’d be depressurized, cooled down and on a residual heat removal system. So they would have water circulating through the reactor, going through a pump and heat exchanger. And then that- on the other side of the heat exchanger, the water would be cooled by seawater. And so they’d be down in a stable state, low temperature, low pressure. Like I said, the exact definition depends a little bit by the design of the plant, but relatively low temperature and pressure.
Q: Thanks. I just wasn’t sure what that meant, so I just wanted you to define it. OK, sorry to interrupt. Go ahead.
A: OK. So we turn our attentions to Unit 1 through 4. And we know that in each of those units, we had an explosion, more significant in Units 1, 3 and 4. We also know that we have partial core damage in Units 1, 2 and 3 and potentially spent fuel damage in Unit 3 and probably very significant spent fuel damage in Unit 4. And they’ve been working to restore electrical power to these units, they actually have power from the grid to these units, but in varying stages of restoration. As of the last updates I saw today, they still haven’t been able to restore any cooling systems in any of these plants. They did start to get some electrical power back to some of the control rooms. And there were some pictures posted today, some of the first pictures we’re getting from inside these plants. Now that they’ve been able to get some electricity and some lights. And there’s quite a bit of damage and apparently in the tsunami, a good portion of these plants were flooded. And so that’s- we suspected that there was probably a lot of damage to the electrical switch gear, which is why, in addition to the diesel generators, why it was so difficult to restore electrical power. So it’s going to take them some time and they said that originally, they were starting to restore systems in Unit 2, because they thought it was the least damaged, but as they’ve worked on it, it’s more damaged than they thought it was. So it’s taking them longer.
Q: And they’ve not only had the flooding, they’ve had all the explosions as well, right?
A: Correct. But relatively-speaking, the conditions of the three units haven’t changed much in the last 48 hours, so they continue to pump seawater in and maintain the pressure under control, they continue to pump seawater into some of the spent fuel pools. And in particular, for Unit 4, they brought in a concrete pump truck and if anybody’s ever seen a concrete pumper, it’s got a very long boom that you can manipulate and it’s used to pour concrete at construction sites where you can’t actually drive the concrete truck right up to where you need to put the concrete and you can pump it with this long boom. And what they’re able to do with that is get a little more precise in getting the water into the spent fuel pool at Reactor 4.
The other thing I noticed in the pictures that were posted today is that it appeared that they were able to get the vehicles a little bit closer to these reactors than they had in the past, which indicates that – to me anyway – that they have been effective in getting water into these pools, which is reducing the radiation levels and allowing them to get a little bit closer. So I think that’s, y’know, we’re looking for positives, that’s definitely positive. The other positive would be that the radiation levels at the site boundary continue to be in the 1 to 3 millirem per hour range, so that’s a good sign, in that the radiation levels at the site boundary now have relatively stable.
On a negative, a couple of times in the past couple of days, they’ve partially evacuated the site because of gray smoke coming from Reactor 3 building. Somewhere in the vicinity of the spent fuel pool. But they haven’t really been able to determine what the cause of that is. And it comes and it goes. So given the amount of water that they’ve been putting on these pools, I don’t know that you would say that it would necessarily be coming from the spent fuel pool, but it’s not clear exactly where it’s coming from, but they haven’t noticed any increased radiation levels associated with this.
Q: Could that just be an electrical problem? Would that create smoke? Because they’ve had so much damage of the electrical systems?
A: Well, since they’re- since they haven’t reenergized the electrical systems, and they’ve been very carefully going through and testing things one at a time. I don’t know what that would be coming from. And it- y’know, like everybody else, we could only speculate, but generally-speaking, if it was coming from the water that they put on the spent fuel pool, it would be more a white steam, like we saw from some of the other units. Because it would be the boiling of the water. So we’re not quite sure what that is and until we can get farther into the recovery and actually get somebody up there, or get a camera up there, nobody’s quite sure what’s going on up there. But the radiation levels have not (inaudible) spiked, which is a good sign.
The other negative news was a couple of workers had to be taken to the hospital, because they got contaminated and an excess dose of radiation. These were a couple of workers that were trying to restore electrical power and somehow managed to step into some very radioactive water.
So that’s my update. Slow progress, but again, it’s been several days now where we really haven’t had any worsening of the condition of the plants.
Q: Which is good, because we said at the beginning, the reason why we felt like at the beginning, we had to do these updates everyday, is that every 24 hours, for the first few days, the situation was dramatically worse. And it seems like now, things are not good, but it seems like they’re not gonna [get] worse than they already were. So allright.
A: You have some questions for me?
Q: Sure I do. I think- as you said this, this situation in Japan with the nuclear power plant is starting to drop off the front page of the news a little bit, as is to be expected, but the main thing that I’ve seen in the news are concerns about radiation in the tap water in Tokyo, in particular, and the one article I read – and you can confirm this with what you know – is that the levels were actually at a point where they were harmful, particularly to infants. And so you wouldn’t want to be drinking that water. Can you talk a little bit about that?
A: So I did see in the news that yesterday, the iodine levels in particular were above the limit for infants and children. And they were recommending people not to drink the tap water. Today, the levels dropped down below, but they were still recommending for children not to drink the tap water. Honestly, given the distance, about 150 miles, I think it is. Or maybe it’s kilometers, I really- I can’t remember from the news report now, to be honest with you, but it’s a fair distance from the plant. It was a little surprising to see as much elevated levels, because I think when we talked about this a few days ago, they were able to detect a little bit of Caesium and Iodine in the water, but the levels were extremely low. And so it is a little surprising that the levels have spiked and gotten above the recommended levels for children. So the only, I guess, good news – if you can say – about Iodine is it has a fairly short half-life. A half-life means half of it will have decayed in a certain amount of time. And if I remember correctly, it’s about 7 to 8 days. So if you don’t have any more being released into the environment, then iodine will not be a problem after a relatively short period of time, compared to some radionuclides that have half-lives of years or much longer. So it’s- I think it’s also good – and we talked about this early on in these interviews – that it was important for the Japanese government to be transparent and it’s very clear that they are doing a lot of sampling. They’re obviously getting the word out and the only real advise I can give people is just to follow the advice that the government is giving you. So if they’re telling you that you should be drinking bottled water, you should do it. When they give you the all-clear, then that means that the levels have dropped back down to safe levels. And our hope, obviously, is we continue to get the situation at Fukushima under control, we significantly slow down or stop any additional radiation from being released and begin to clean up and address the problem.
Q: And bottled water is OK because that bottle is basically like your clothing or your skin, providing a barrier from that radiation that can be harmful, right? So that water isn’t going to be contaminated, because it’s been sealed up properly.
A: Well, as long as it was bottled somewhere with water that didn’t have any contamination or-
Q: Right, presumably, it was bottled before the nuclear disaster or from a location further away.
A: In Tokyo, the concern is not that there’s contamination in the air or in people’s houses or in the streets, it’s gotten into the water because probably rivers closer to the plant have flowed into other rivers where they use as a source of the water.
Q: OK, well, I think that answered my question.
A: I wish I knew Japan geography a little bit better.
Q: Me too.
A: But I only have been there once, so…
Q: I’ve never been there, but we’re doing the best with what we have, so… I think that answers that question and again, it sounds like the Japanese government is being very straightforward with people and giving them clear directions.
A: From what I’ve heard, there’s a lot of sampling going on, they’re getting assisted by the IE- boy, I can never say those 4 letters.
A: International Atomic Energy Agency, with monitoring teams. They have help, obviously, from United States and they’ve identified several vegetables that- and milk that they’re not allowing to be consumed from that area. And obviously, they’ve been transparent in respect to the situation with the water in Tokyo.
Q: That’s excellent. So people need to just listen to the advice of the government, it sounds like they’re doing a good job.
A: And obviously, Tokyo’s the one that makes the news here, but my hope is they’re also being transparent about other cities that are maybe closer and may also be of concern.
Q: All right. Well, let’s move on to the next question. So this is an article that actually I saw in the news and I’ll post a link. I saw this on CNN, actually, and it was just a short article, but it was talking about there are some companies that make bomb shelters and these were very popular during the cold war, when there was fears about nuclear war. And I guess they normally sell a certain number of these shelters per year, but in the last couple o f weeks, since there was a situation in Japan and presumably other current events, like the situation in the Middle East going on. There’s just been a huge, I guess, increase in the number of requests that they’ve had to build these shelters. And I was just wondering if you could comment a little bit about bomb shelters and about being prepared for disasters, and I guess in particular, a nuclear disaster.
A: Well, I actually haven’t seen the article, so I’m not exactly sure of what these bomb shelters consist of, but I think I can speak to being prepared, so… I live in New Hampshire and we obviously have very severe storms during the winter. And it doesn’t happen very often, but every once in a while, we will get a snow and an ice storm that will cause extensive power outages. A couple years ago, we had one and the power where we live was out for 4 days. So you do, I think, have to be prepared for natural and other disasters. And one of the things that we did at our house was we normally have oil heat here, which is very common in New England, it requires electricity to run your furnace. So we installed a couple of propane heaters that don’t require any electricity and we can use those when the power’s out to keep the house warm. We also have a- I keep in the basement – a kit with radio, flashlights, batteries, candles, bottled water, so that in addition to what food you should keep on hand that doesn’t require a lot of preparation work, or cooking, or electricity, that you basically have enough food and water on hand to last 2 or 3 or 4 days. And I think that’s good advice for most people to follow, and then depending on where you live, if you’re in an area along the coast, where you might be subject to hurricanes or typhoons or if you live somewhere where you might be subject to flooding and maybe be cut off. Or if you maybe live in the north, where you have severe winter storms and you might have a loss of power for a few days, I think it’s always good to be prepared. I’m not so sure about the bomb shelters. Certainly in the Mid-West of the US, we have a lot of threats with tornadoes and people often have tornado shelters, which are typically underground. So I can’t really comment on these shelters because I haven’t seen it, maybe if you send me the link, I’ll take a look at it.
Q: Well, they seemed very extensive and it sort of seems a little bit extreme, like preparing for apocalypse, and so they sell you these things- I’ll put the link up on the website, but so you know, it’s 200 thousand dollars or a million dollars for the shelter, and that seems a bit extreme to me.
A: I think common sense. But I think most people probably don’t prepare for the fact that they might be without heat or power for a few days. Now, clearly, in parts of Japan, it’s a more significant problem because if your house wasn’t damaged from the earthquake and the tsunami, there’s going to be areas where it’s going to take them months to restore the electrical grid and get power back to everybody, I don’t think you can ever prepare for that. And that’s why you need to have the relief agencies and the government, but for the average person, it’s probably not far-fetched to have enough batteries, have enough food that doesn’t need preparation, have some bottled water, so that you can go at least a couple-3 days. That would be my advice.
Q: Sounds like that’s an easy thing to do and would be useful in many situations, many natural disasters. OK, I hope there’s not too much background noise, I’m in my office late at night and they’re actually vacuuming outside, so I hope that’s not getting picked up, but if it is, I’m sorry, hopefully it’s quiet. So let’s move on, are we done with the shelter question?
A: That’s all I can answer.
Q: OK, so this question, maybe you can speak to, I know we talked yesterday about Vermont Yankee and renewing the license, but one thing that we didn’t address is people are obviously very concerned about having some of these passive cooling systems. In the case, Vermont Yankee presumably has- is attached to the grid and has generators and has batteries. But in Japan, we’ve shown that even if you have all that, there can still be problems. So you had talked a little bit – though not in detail – about these passive cooling and I guess the question is do they have any of that at Vermont Yankee, are you aware of that? And is it possible to take an older plant, like Vermont Yankee or Fukushima, and actually retrofit it with some passive cooling systems that would work if there was no electricity, basically, or no power?
A: All right, let me try to answer the question in a couple ways. And I’ll go back, I think, gosh, maybe in the first interview, we talked about needing to take a lessons learned from this and take a look at the design basis of these plants and make sure that given what’s transpired, that in fact, what we’re assuming of the design basis, or the worst-case scenarios is in fact still accurate. And I did see that the Nuclear Regulatory Commission in the US is going to kick off an investigation and take a look at the safety of the plants in the US. And other countries around the world are announcing similar type initiatives. I think the European Union is going to try to get together and come up with a common process, but I think that’s very important. And I think it’s important in the context of this question because whether or not a plant should have more or additional safety systems depends, I think, on the design basis. And the current state of the safety system of the plant. So, y’know, what got us here was two events that were obviously related, that were beyond the design basis of the plant. The earthquake, which was beyond what was designed for, and then the tsunami, which was – as we talked about, I think, two days ago – double the height of what the plant was designed for. And that’s what got them in the situation where they had a loss of power and a lot of damage. If there’s plants that we look at and we find out that what we took into account for the design basis is no longer correct, then there’s gonna have to be remediation at those plants to either add or modify safety systems to make sure that the plant is safe.
So the second – to answer the second part, about the passive safety systems, I think it would be very difficult to modify these older plants with some of these newer design features. And it’s because- it really almost has to be taken into account with the plant design to begin with. So with the passive cooling, they have to accomplish a couple of things. First, the- one of the bigger design requirements for a nuclear power plant is for what we call, loss of cooling accident. And that would be where you would have a major pipe break. So we know we have to pump water out the reactor and back in. If one of those big pipes was to break and water would be coming out of the reactor at quite a fast rate, we have to have enough pumps and water to keep up with that and keep the reactor vessel filled. In the passively-designed plants, they have systems with tanks where that water would flow without the aid of pumps. The second thing that they have to be able to do is cool the reactor. And again, in the older designs, like Fukushima or you mentioned Vermont Yankee, that would be done with needing electricity and pumps and heat exchangers and those types of things. In the newer designed plants, they take advantage of natural convection, where warm water, or warm air will rise and cold water or cold air will fall. So in the design of the plant, the piping systems and the interconnections to where the natural cooling system would be, you have to make sure that you wouldn’t have too much flow resistance, so too many turns in the pipes, the connections where these would tie in would have to be at the right places, so that you would get the natural convection flow. And so it’s something really, for both of the cases, the systems that would allow the reactor vessel to be refilled in the event that you were losing water, and the cooling systems that would take advantage of natural convection, have to really be designed as part of the plant because to go in a retrofit that would be very difficult because for sure, the piping and the penetrations are not probably going to all be where they need to be in order to have this unassisted flow.
Q: But there must be some things they can look at, I mean, I’m sure they are doing this and it sounds like they’ve formed a committee in the US, the NRC, to take a look at this. And we talked at the very beginning about the generators being flooded at Fukushima. And it sounds like, I don’t know how possible it is, I know that these are very large generators, but if you can somehow put them a little higher up? I don’t know if you can put them on the roof, if they’re too heavy, but it seems like there might be some modifications that you could do, so that even in the case of the tsunami, or a Nor’easter for Vermont Yankee, there could be some things you could do – extra batteries – something so that you could make it so that a loss of power from the grid wouldn’t be such a huge problem.
A: Exactly, but it would probably be unrealistic to – from a design perspective – to be able to retrofit passive systems into these plants. I know it’s kinda hard to understand without any graphics or pictures of what I try to explain, but if you’re counting on warm water to rise, go up to a heat exchanger and cool and then come back down… if you have too much flow resistance, so if the pipes have too many turns in them, or too much of an elevation change with a turn and the water won’t be able to overcome that flow resistance, so even if the water’s warmer, if there’s too much resistance, it still won’t flow. It would be very, very hard to retrofit that, that’s something that’d be in the design of the plant and all the pipes and everything have to be in the right places to make that work to begin with.
But you’re absolutely correct, if it turns out that some power plants, based on looking at it, are more vulnerable or the assumptions or the design basis earthquake, or the design basis flood are not valid, or conservative enough, then that will have to be looked at and modifications need to be made. And there maybe, in some cases around the world, where it’s determined that there’s nothing that can be done and this plant is really is not safe to operate. And what we thought- what we’re starting to find out in the past couple of days is that it wasn’t just the generators and some of the electrical that was flooded, but apparently, the tsunami was such that a good portion of these plants themselves actually got flooded. So that’s why it’s taking so long, because not only was the generators and some of the electrical systems associated with the diesel generators flooded, but apparently water was actually in some of these reactor building from the ocean and pumps and valves and those types of things were also flooded and damaged.
Q: Well, that’s a pretty significant observation and I agree with you, there probably are some nuclear power plants that they will determine are unsafe to operate and that becomes a pretty big deal, because nuclear power plants generate quite a lot of electricity, so to remove one would be a big stress on the grid, I would imagine, but if it comes down to having another Fukushima, better to have some stress on the grid and try to come up with a solution than trying to operate a plant that’s not safe, in my opinion.
A: Absolutely. And I would think that, that’s something that everyone would agree on, whether you’re a nuclear engineer making your living or whether you’re a concerned citizen of the public. If it’s determined that we’re beyond the design basis, then either we come up with a plan to remediate the plant or if we’re not able to do that, then we do need to shut it down. But what I think we’re gonna find, at least in the US, is that’s probably not the case, that my guess is we’ll find out that we’re in pretty good shape. And probably the biggest concern, based on what we have, are the plants that are located closer to the ocean and you mentioned – and you know a lot more about geology than I do – that relatively speaking, the East Coast of the US is not really subject to the kind of event that we saw in Japan.
Q: No, again, the East Coast, it’s- again, I posted a link to this, but it’s what’s called a passive margin. So the reason that there was an earthquake in Japan is because you have, actually not just 2, but 3 tectonic plates that are interacting and sliding under each other. And that’s what generated the large earthquake and tsunami. In the United States, it’s not that we can’t get a tsunami, but because we don’t have what’s called an active plate margin, where you have either plates that are sliding past each other or going under each other, there isn’t really a good mechanism right on the East Coast of the states, to generate a large earthquake or a large tsunami. It would be much more difficult.
On the other hand, on the West Coast, you have the San Andreas Fault, where you have two plates that are moving past each other, and further north, that actually changes from sliding past each other, to actually what’s called a subduction zone, where you have one plate going under another and that’s why, for instance, you get Mount St. Helens and volcanoes there and again, look at the link, if you want to understand the geology a little bit better. But there is a potential on the West Coast, to have large earthquakes and to have tsunami-generating earthquakes and so those are the plants that we should look at most closely. And I’m not a geophysicist, I’m not an expert on earthquakes, I have many friends who are and there is a potential for large earthquakes on the West Coast and I think people who know more about that – I’m a geochemist, not a geophysicist – should really look at that hazards assessment, I’m sure that United States Geological Survey has good estimates, good hazard estimates, but they should look at those and they should check each plant and, as we’ve said, the design basis for that plant to make sure that it can endure- y’know, we thought Japan – we didn’t think we’d get such a large tsunami there. That wasn’t in the design basis, but they should check and make sure they really know the worst-case possibility is. I guess they do this with probabilities. And that design basis for nuclear power plants on the West Coast is within that design basis for both an earthquake and an associated tsunami.
A: So a couple days ago, somebody asked what the viability of the reactors were at Fukushima. And we said, well, 5 and 6 were physically separated and they were not as badly damaged. And they didn’t have any core melting, so it might be possible that those plants can be repaired and restarted. 1 through 4, because of the extensive damage, because of the core melting, those plants will never operate again. So we also mentioned that would it be safe? Given what we now know is the design basis of these plants, is it possible to protect Units 5 and 6 with a construction of a seawall or some other barrier that, assuming that they could repair and decontaminate those plants, that it would be safe to restart them. And that’s a question I don’t think anybody’s looking at yet, but that would be an example where unless we could do something like that, that it would not be safe to restart those two units.
Q: And those two units, they were less-damaged. Do you know, where they less-flooded, I mean, because of where they were, did they get hit less by the tsunami, was that just luck of geometry? I mean, they’re right on the coast like the other ones, right?
A: I really don’t know. From the pictures, which are mainly satellite views, it’s hard to- it doesn’t appear that there was any significant difference in elevation, but again, I imagine if you were at the site, it’ll look a lot different than it does in the satellite, so…
But again, that would be a case where that has to be looked at. And we also mentioned that the Fukushima 2 plant, which is 7 miles away and has 4 reactors, fortunately, they were able to recover those plants a little bit quicker and get them all into cold shutdown. But that site needs to be looked at as well and it may turn out that Japan, for instance, might have several reactors that either they’re gonna have to do some significant seawall building or remediation before it would be safe to continue to operate those plants. And although we have quite a few nuclear power plants in the US, if you actually look at them, the vast majority of them are inland, at least some distance, but again I don’t think we stop at the earthquake/tsunami scenario, we have to go back and look at the actual design basis for all these plants. So what’s the worst-case tornado? What’s the worst-case flood? What’s the worst-case earthquake? All that design basis has to be looked at and we have to validate that our assumptions are correct. And if they’re not and we need to be more conservative, will the plant still meet that design basis criteria or not.
Q: And flooding is a very important one, because that’s what did much of the damage at Fukushima. And also because nuclear power plants require cooling, they’re often on a river or a lake or a body of water that could be in a flood situation.
A: But again, so I don’t think we can just focus on flooding, we have to look at the design basis, because if you have a plant that was designed for, say, a worst-case earthquake of 3.0 and we find out in fact, that the worst-case earthquake now, we might say, is a 3 and a half or 4, then that could be a problem in that, that plant and its piping wouldn’t have enough extra supports and hydraulics…dampers and those type of things. And what would you do in that case? Well, what would happen in that case is we would have to shut the plant down, we would have to make those modifications and….before we would be allowed to start it back up. Or if we determine that it was cost-prohibited to do that, we would just have to shut the plant down and retire it. So again, I want to emphasize that – and I’m confident that the NRC and industry will do this – is to go look at the complete design basis, and not just worry about a tsunami or an earthquake or whatever. We’ve gotta look at all of the criteria for these plants.
Q: Just to say one last thing about Japan, from a geological perspective, I mean, the way that Japan is, there can be large earthquakes and earthquakes are different and large earthquakes are different. There are some aspects of them, but they can happen and slightly different geographical places, they can be slightly more deep or shallow, and the tsunamis that are generated by these earthquakes can sort of take different forms and can reach different places. I mean, had the earthquake and tsunami been slightly different in a very similar, also geologically-plausible situation, Fukushima 2 could’ve had the problems that Fukushima 1 is having. Just based on, coastal morphology and the way that the tsunami was generated, but really any power plant that’s close along the coast of Japan is susceptible to this sort of event and I think Fukushima 1 just got unlucky with this particular earthquake and tsunami.
A: And the last thing I would add is my guess is when we do go look in the US, I would be surprised if we came up with too many issues. And one of the – one of our advantages, I think, is that a lot of our plants are older, because we haven’t built- after Three Mile Island, we haven’t built many plants. And so what’s happened is the original license for these plants – and we discussed this in one of the interviews – was for 40 years.
A: And then the plants had to apply for a license extension and they had to do a lot of engineering work. They had to do a lot of work in the plants, replace components, which they do a lot anyway, for maintenance. But they also had to do a lot of design work to prove that the plant was still safe to operate for another 20 years. So for most of these plants, where they’ve already done this, they’ve already gone through a very extensive study to show that the plant is still safe to work at, so unless, y’know, some new information comes to light – such as we determine there’s a new fault line or something more severe than we currently know – because the plants are older, then it had to go through this relicensing process. A lot of this stuff relatively been recently looked at for a lot of these plants.
Q: Because so many of them have – for instance, Vermont Yankee just was renewed at 40 years, so they just looked at Vermont Yankee.
A: They literally just got the green light from the NRC a few days ago. And- like I said, they’ve had to have gone through an exhaustive review and study of the plant against the design basis, to prove that it was safe to operate for another 20 years. And so, like I said, I would be surprised if we uncover a lot of problems. But again, I think it’s incumbent to imply new lessons learned and go back and do some review. So I don’t think anybody that lives near a plant should be in panic mode, because, like I said a lot of this stuff has been looked at very recently. And there’s other places in the world where all their plants are relatively new and so-
Q: Is France, for instance? I don’t know where that would be.
A: Well, France has a good combination, they have a lot of older plants, they have a lot of newer plants, but what I’m saying is the plants that probably might show up as having a concern, maybe, are the ones that are kind of in that mid-range. Maybe they’re 10, 15 years old and we go back and look at it and say, oh, you know what? We originally assumed this and now we could expect that event, whenever it is, when- flood whatever – maybe to be a little bit more severe, because it hadn’t been looked at in the last 10 or 15 years. But like I said, a lot of cases in the plants in the US, they’ve just recently gone through this exhaustive process where they’ve had to leave no stone unturned to justify the right to continue operation, to get that license extension.
(stopped at 45:05)
Q: And there are some plants where they turned down that license renewal, isn’t that correct? There are some plants that reached that 40 years and they found a problem and they, or, I – It could have been political, so, I don’t know, but they found some problem and didn’t renew it because of that extensive review.
A: Yea, I honestly, you know, because I haven’t worked in the industry in a number of years, I haven’t really kept up. Ah, I’m not aware of any plant that applied for a license extension that didn’t get it.
A: But, there are plenty of plants where the decision was made that they would just shut down because the, the cost of continuing operation or the cost of modifying them to bring them up to current safety standards wasn’t worth it. And I know there are a couple of plants in the country where there’s a concern about environment impact. These are older plants that were build before, ah, there were as many requirements for cooling towers, and, I know that in the case of a couple of those plants, that they are considering shutting them down because the cost of building cooling towers is not economical.
Q: Ok, well I’ve got one last question for you related to this actually, and then we’ll be done. Um…So…When they do decomission the plants, they do have all this spent fuel.
Do they leave it in the spent fuel pools at the plant? Right now, in the US, there isn’t any other place to bring it, right?
A: So…because there isn’t any other place to bring it, initially it would be in the spent fuel pool. But, it…it takes quite a period of time to decomission a nuclear power plant. The goal, in most cases, is to return it to a “green field” condition. In other words, you’re actually gonna tear it down so, ah, thats gonna take quite a bit of planning and work in order to accomplish that. So, while the pool…the fuel would initially be in the spent fuel pool, over time, obviously, it’s gonna cool down to the point where you could move it to the dry cap storage we talked about
Q: Um hum.
A: And so there’s a plant, ah, not too far from where I live, maybe 40 minutes away, with the Yankee Row Power plant. And, that was decided to shut down quite a few years ago, and they decomissioned the plant and removed the plant, but the fuel is sitting still, in a guarded area, a concrete pad in, in the dry cap storage area. So, that’s, until there’s a solution in the US, ah, for the government to take these , ah, fuel assemblies or fuel rods, then it’s gonna have to be something like that.
Q: Does the power plant pay for that storage? And, how does that work?
A: Well, we haven’t really talked about it, but, believe it or not, everyone in America pays for that storage. It’s actually a law that the Federal Government had to take possession of the fuel, and, there’s a charge that’s made, ah, you know, to the nuclear utility, which is passed on to the people that buy the electricity for the government to take the fuel and the government never has. So, ah….
Q: So we pay for something we don’t get? Wait! (laughs)
A: Yep. ah….
Q: Hum…We’ll discuss this more, maybe later.
A: but, in any event, the Federal Government is supposed to take possession of the fuel and it was supposed to go to Yucca Mountain, and we talked about that on one of your interviews. …Decided not to do Yucca Mountain and the government has not come up with what they are gonna to do, so, in the interim, it’s gonna have to be stored in these dry cask units. See, when the plant is shut down, the fuel will be too warm,and it will be in the spent fuel pool but, after a few months, or a year or so, it will cool enough that it can be put in dry cask storage. So, they would…if they didn’t already have one, they would build a dry cask storage unit, and that’s where it would stay, and, they would go ahead and dismantel the rest of the plant.
Q: Well, I was just thinking; and, obviously, this becomes less of a concern the longer the fuel has been out of the reactor, but, at Fukushima, we learned that just because a reactor is shut down it doesn’t mean there can’t be a problem. We’ve had significant problems with the spent fuel pool, so, you know, after these plants are decomissioned, they’re still going to be in a hazardous area, and the fuel, which has been spent, but, is still hot, is still gonna be, you know, subject to those same environment hazards, so if you determine that a plant, there’s just too many natural hazards for it to operate, you have to not only shut down the plant, but, you actually…to me it seems you have to move the spent fuel somewhere else, away from that hazard as well, cause that can have just as much of a problem as the reactor, potentially.
A: Or…Or take some other compensating measure.
Q: It seems that would not be as much of an issue as an operating reactor, but could still be a problem.
A: It, It…could be a problem, but, you know, clearly you can’t move the fuel right away. You have to come up with a plan on how to compensate it. So, let’s say that the concern was risk of loss of electrical power, because maybe the generator, or switch might get flooded. Then we’d have to come up with another plan where we’d, maybe have a generator or something or, ah, some kind of temporary system that could be brought up quickly, to provide cooling for the spent fuel pool that wouldn’t rely on the components that would be at risk.
Q: Maybe something you could bring in by ship, that you could set up quickly
A: Well, again, most of…if you look at it a lot of the plants in the US are not near the ocean
Q: I was thinking for Fukushima. Ok. Sorry to keep asking you questions! You keep giving me a hard time because I ask too many questions! I’m curious.
A: OK (Laughs)
Q: And I think other people are curious too, so… (laughs). Alright…
A: So…yes…if you were in a situation you know, where we determined there was danger and we had to shut it down, and the reason was lack of some kind of power, or whatever, then, yea, it would be very prudent so have some kind of fall-back system, ah, that, ah, would not be subject to the same risks until you’ve reached a point where that fuel has cooled off enough that it would…it wouldn’t need it.
Q: Ok. Do you have anything else to say before we end?
A: I don’t!
Q: And, I guess my other question for you is when would you like to next do an interview?
A: It would have to be tomorrow evening.
Q: Sounds good. I will talk to you tomorrow evening!
Q: Ok…Bye, Dad!
Accidentally linked to Interview 10. Fixing now…
I've transcribed up to 45:05. If someone could take over and transcribe the last 10 minutes, that'd be awesome! Thanks!
The Fukushima reactors have been cooled by being sprayed with seawater. The seawater contains salt that will remain behind after the heat has evaporated the water. What are the risks of salt to the reactor's system of valves and pumps? Is there a risk that the cooling systems will be damaged even more by this? Thanks,Marc
Great question, Marc!My dad and I actually discussed this in Interview 12, which I just posted.
Still screeched to a halt with the transcription? Let me know at x m u n d t (at) gmail.com and I will be happy to finish it off.