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
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.
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.
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.
Q: So, another question I have for you, is one of the main problems they’re having in
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.
Q: So they’ve actually shut down the plant in
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
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.
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
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.
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
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.
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.
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.
Q: To use sea water to cool it –
A: I think they’re basically down to their last option here.
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?
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.
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?
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.
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
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.
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
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
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.
Q: OK, thank you so much, Dad, for all of your insights. I’m so glad I have a nuclear engineer in my family.