KPBS Radio is undergoing scheduled upgrade work which may result in temporary signal outages.
Nuclear Expert Reacts To Latest At Fukushima
Wednesday, March 30, 2011
Japanese officials remain convinced that the nuclear crisis at the Fukushima Daiichi plant will be brought under control. But 20 days after the devastating earthquake and tsunami, efforts continue to contain radiation from badly damaged nuclear reactors.
Japanese officials remain convinced that the nuclear crisis at the Fukishima Daiichi plant will be brought under control. But 20 days after the devastating earthquake and tsunami, efforts continue to contain radiation from badly damaged nuclear reactors.
Yesterday, Japan's prime minister said the situation at the nuclear site remains unpredictable and the country remains in a state of maximum alert."
Dr. Murray Jennex, associate professor at San Diego State University. Professor Jennex is an expert on nuclear reactors.
Transcript DisclaimerThis is a rush transcript created by a contractor for KPBS to improve accessibility for the deaf and hard-of-hearing. Please refer to the media file as the formal record of this interview. Opinions expressed by guests during interviews reflect the guest’s individual views and do not necessarily represent those of KPBS staff, members or its sponsors.
CAVANAUGH: I'm Maureen Cavanaugh, and you're listening to These Days on KPBS. It's been 20 days since the devastating earthquake and tsunami hit northern Japan, and the latest news about the damaged Fukushima Daiichi nuclear power plant is not good. Officials say radiation detected in the sea water near the plant is at its highest radiation level yet, more than 3300 times normal. Yesterday Japan's prime minister said the situation at the nuclear site is unpredictable, and the country remains in a state of maximum alert. I'd like it welcome my guest, doctor Murray Jennex, associate professor at San Diego state University. Doctor Jennex is an expert on nuclear reactors. And doctor Jennex, welcome.
JENNEX: Good morning, Maureen.
CAVANAUGH: Now, first of all, I know that you've been doing your own checking on background radiation here in San Diego. And in following your twitter feed, there doesn't seem to have been much of a change; is that right?
JENNEX: That's correct. It's actually the background stayed very level.
CAVANAUGH: And is that what you expected?
JENNEX: Yes, it is.
CAVANAUGH: So let's move if we can to the situation in Japan, which is very different. And what is the latest that you've heard from your contacts in Japan?
JENNEX: Well, you know, they have been finding a little bit of plutonium outside of the plant, but not in any levels that indicate any kind of leakage from the containment structure. What they're finding is almost like back ground there. However, other contamination is pretty heavy. It's around the plant, it's in the plant, of course you mentioned it's in the sea water. So from that standpoint, that's been an ongoing issue. They're gotten the power lines to the plant, but they haven't been able to restart any pumps, although they got the lights on in a significant improvement, it does take a few days to put the pumps in order. They have to dry them out otherwise they tend to have an ark and cause another explosion which they don't need. There hasn't been any fires really, so it's been kind of stable, stable in an unstable situation.
CAVANAUGH: Right. Now, talk to us a little bit more about the plutonium that was discovered in the soil near the Fukushima plant. You don't seem to think that that's a very bad sign.
JENNEX: Well, it was a very conflicting report. What they said is they found levels that were -- that did not affect your health, and from analysis, it seems to be levels that they would have expected given from regular fallout from the World War II bombs. But then you had a Japanese official say, well, it seems that we had a leak in our unit three containment structure. And I wasn't -- when I read that, I was very perplexed, and when I've talked to people, people don't understand what they're trying to say, because that level of plutonium would not indicate a leak in the containment structure. You would have actually very, very significant level was plutonium. And that would be hutch higher of that's why it's kind of of a confusing situation in Japan there. Information they have been putting out has been slow and not real accurate.
CAVANAUGH: And doctor Jennex, can you speculate as to why that is? Is it because it's just so terribly difficult getting information from that site?
JENNEX: Well, I think part of it's -- they're tied up doing all the work they need to do getting their reactors under control. So they don't have people who really know things available to talk. So that's part of it. I think the other part of it is they don't want to say anything until they're absolutely certain. Otherwise it doesn't look good, like a couple of days ago, they said they have radiation levels at 30 times normal. Well, it turns out that was a mistake in reading. That probably somebody messed up the rain switch, and it was actually a couple hundred times less than that. So that's what happens when I think they try to rush out information. The same thing, I think happened with this report that oh, a little bit of plutonium means that they have a containment structure leak.
DEFENDANT: It doesn't mean that at all, but I think that person was trying to be open because they received a lot of criticism about not putting out information. And as a result put out bad information.
CAVANAUGH: Now, from what I understand, doctor Jennex, people -- some officials or workers in Japan, perhaps colleagues have been contacting you because you are something of an expert on this type nuclear containment facility. Is that fair to say?
JENNEX: Well, I tested nuclear containments for 17 years, so I tested for leak tightness. And I've been getting questions from people in Japan, primarily because a lot of the information's been done on TV, it's been looking at a very simplified version of what their containment structure looks like. And as a result, they're making some -- I couldn't say terrible conclusions, but misleading conclusions, and so I've been guiding them into what I would expect to be really happening.
CAVANAUGH: Can you -- I know much of this is probably extremely technical. But is there anything that you can tell us that would compare what perhaps the simple explanation is as opposed to what the actual explanation is.
JENNEX: Well, one of the things that -- CNN in particular keeps pointing out and other media is that they're always worried about a containment structure breech or a tear in the containment structure. Actually, the containment has about 60 different pipe penetrations through it. And it's these penetrations that are the weak points. Weaker than the actual six inches of steal. So if they're speculating on an actual containment break, it's more likely gonna be a pipe breaking or valve failing in one of these penetrations than it is the seal itself tearing.
CAVANAUGH: I see. Okay. And that kind of simplification actually is not helpful, is it and.
JENNEX: No, because that raises fears that if this structure tears, you cannot fix it. That's also not true either. But it also raised fears it's gonna have an uncontrollable release of information, and these containment structures are actually doing what they're designed to do, they're holding the nuclear material in. And to be quite honest, I think a lot of the radiation that's out there now is coming from the contamination that's come from the equipment that was above the reactor vessels and outside the containment structure. And also from the fuel pools which caught fire.
CAVANAUGH: I see. I'm speaking with doctor Murray Jennex, he's an associate professor at San Diego State University and an expert on nuclear reactors. We're taking your calls if you would like to join the conversation, if you have a question about what might be going on or something that c Jennex can address, give us a call at 1-888-895-5727. That's 1-888-895-KPBS. I think that what you might have been referring to, and what was the announcement that was issued yesterday was Japanese officials saying that finding plutonium in the soil, and a high density of radiated water at the plant meant that some of the nuclear fuel has melted. Now, do you think that that is an over reaction to what has actually been found?
JENNEX: Given that the levels I saw reported were incredibly low, yes, it is. For that melted fuel to get out would have required a leak somewhere. And it would have been a much higher level. And now, they do have melted fuel. They caught fire in their fuel pool, and that burned some of the fuel, and that exposed the atmosphere, but none was that was plutonium fuel. That was just uranium fuel, and that's where the vast majority of contamination is coming from.
CAVANAUGH: Now, if indeed, let's say that what we're saying is the level of contamination that there's been. It's been sort of a burn off contamination rather than a melt down. Tell us what kind of danger will exist around that plant and for how long.
JENNEX: Well, how long is gonna be many years at the minimum. What level of contamination, primarily get the contamination being carried off by smoke and steam, and relatively smaller explosions there on the site. And by small, I'm comparing them to what was at Chernobyl which had a very large steam explosion and which shot things way high into the air. And that actually is a key factor, that they haven't pushed stuff real high into the atmosphere. So what you're getting in is fallout in a pattern away from the plant. But it decreases fairly quickly. Now, how far out it goes, we won't know until they're able to do surveys. They are already finding contaminated milk, they are already finding contaminated spinach and other vegetables, and I do imagine it's gonna be at least contaminated for some 20 kilometers outside the plant.
CAVANAUGH: My guest is doctor Murray Jennex, we're taking your calls at 1-888-895-5727. Justin is calling, he's driving on the freeway. And good morning, Justin. Welcome to These Days.
JUSTIN: Hi. Thank enforce taking my call. I had a question regarding the electricity that was being used to power the coolant pumps and other systems around the power plant. I would like to know why they wouldn't be able to bring in diesel generators from outside sources like air lift them in, or why couldn't they use electricity generated from the facility itself to power their own systems.
JENNEX: Well, the main reason is these pumps run off of very high levels of power. They're like 480-volt pumps. So the type of generator you need to generate that level of power is pretty massive. And you don't really have these generators sitting around. So that's why they really couldn't just air lift one in. They probably didn't have any sitting around. Of and you couldn't unhook them from the other nuclear the sites in Japan because they needed their back up power in case something happens at one of these other plants. And even if you do air lift them in, where would you set it? These are fairly massive generators. 20, 30 feet long, 10, 15 feet wide, many, many tons, they're very heavy. So you just can't set them down were any. So there's a lot of reasons why they couldn't air lift a diesel generator in.
CAVANAUGH: We have another caller on the line. Dan is calling from Point Loma. Good morning, Dan, welcome to These Days.
DAN: Thank you. I have a question about this radiation that's leaking into the ocean. What kind of danger does that cause to -- I realize it's dangerous to Japan, but what kind of danger or problems is that gonna cause to the rest of the world, even here to San Diego and to the ocean, and the ecosystem that you know? Thanks, that's my question.
CAVANAUGH: Thanks Dan.
JENNEX: Well, probably minimal outside of the Japanese home waters. I do anticipate that anything that deposits near the plant will settle down to the bottom right here the plant, ask your gonna have contaminated ocean around that plant for many, many years. And from the standpoint of harvesting fish and shrimp and lobster and stuff, it's not gonna be usable. They're gonna have to avoid fishing there until they can clean that up, and it's possible to clean up. Anything that gets caught into the current and taken out into the middle of the ocean, the vast majority of that is going to fall to the bottom as it flows. And since we really don't fish the middle of the ocean, and it's very deep, a lot of that's gonna drop down to the ocean where it's really gonna have no impact on us. And I know that sounds like we're saying hey, don't worry. But in a way it is, because these particles are very heavy. They probably won't carry long distances, and at some time we'll detect some ions around different parts of the world, but the vast majority of it is going to fall down to the bottom of the ocean.
CAVANAUGH: I have a question about that, pause you said that the last time you were on our show, doctor Jennex, and won't that work its way into our food chain though? Even though it goes way way down into the bottom of the ocean? Isn't this some way this it's gonna eventually get up to the kinds of things that we eat?
JENNEX: Well, not if it's out in the middle where it's really deep. We do most of our fishing and harvesting from coastal waters and shallow waters. So anything right this next to Japan in the shallow waters, that is gonna be contaminated we won't be able to eat. They won't be able to use that. I agree with you there. But the stuff that carries out deep, we don't really harvest.
CAVANAUGH: Okay. We have a caller on the line, Dr. John Hood, Physicist Doctor John hood, welcome to These Days.
DR. JOHN HOOD: Yes. Doctor Jennex, I'm an old guy, I'm a retired physicist, optics was my field, not nuclear physics. But I had two questions. The first one is, I'm listening to newscasts and no one ever talks about the possibility of using vast neutron reactors or other things that could actually burn up waste. And we always talk about waste when it's actually really a fuel, and the other thing is, can water actually be con -- or can it become radioactive? The news people say the water is radioactive. It's really something in the water. Is that not true?
JENNEX: You're right for the most part on the water. You can activate the nitrogen, you can activate hydrogen and oxygen in the water. So it does get radioactive, but it's only for a few seconds. I think the half life on the oxygen in the water is about 15 to 20 seconds. So it cycles out, it's radioactive for a brief period of time.
CAVANAUGH: And workers actually at the plant have been burned by that water in that very short period of time; is that right?
JENNEX: But not that radiation.
CAVANAUGH: Oh, all right.
JENNEX: The caller is right. The vast majority of the radiation in the water is actually contamination that's been captured there by the water dissolving it, as it flows down the sides of the buildings, and as it flushes out of the fuel pool. That's where most of the radiation is coming from is actual physical contamination. And that's why it's not really a surprise that it's very radioactive down at the bottom of that plant, because that's where everything is flowing to.
CAVANAUGH: I see. You want to address the neutron reactors at all?
JENNEX: Well, the vast readers, they've been a concept, they've been around for a long time. The problem is that to run them, you really have to rely on computers, and most regulators in the public are not ready to totally rely on the reactor run by computers and not by humans. So that's why we haven't really built them. It's been more of a psychological licensing issue than something we couldn't do. And now probably right now it's probably good that we haven't got any.
CAVANAUGH: I see. How about if people are traveling to -- not necessarily Japan, but in the area of southeast Asia. Is there any special concern that one might have in that area of the world?
JENNEX: Well, probably not. You'd have to rely on local readings to see if there's been any real increase in contamination or background radiation. I haven't seen anything that's said that any other location is having any kind of significant radiation, so I wouldn't be too concerned about contamination in the atmosphere. In the food chain, again, they're gonna be having to test. And it really depends on where you're headed to. In fact, a local country has good testing programs and monitoring program, they'll probably be okay. If they don't, I'd be a little bit concern body you not overly concerned.
CAVANAUGH: Doctor Jennex, finally, what do you know about what actual plans there are for stabilizing the Fukushima plant?
JENNEX: Well, it is stabilizing as we speak. Part of the problem, what caused the massive heat in the first couple days, is when you shut a reactor down, you have a build up -- there's already a build up of poisons in the reactor, which actually have to decay away. And these generate huge amounts of heat. So after initial shut down, you have a couple days when you're generating lots of heat, and then that starts to slow down. And now that they're, well, what? 20 days into this event, a lot of that heat has dissipated away, they're still generating heat. But at a much lower level. So that's helping them get control of the plant. And also to get total control of the plant itself, we're gonna get cooling reinstated into the systems, if the pumps are working. If not, they're gonna bring in other pumps, they're gonna start rigging systems to help circulate water throughout the reactor course. Now, to me, the real issue, the hard part to get under control is gonna be these spent fuel pools where they have had exposed fuel, and some of them catch fire of that's gonna be very contaminated, very difficult to control. They're gonna have to cover it up with water, let it cool down, and then they're gonna have to try to clean up you will the contamination which is generated in the fuel pool, which is now open to the environment.
CAVANAUGH: I see. And how long would you estimate that might take?
JENNEX: Well, this cleanup is gonna take years of once they get the reactor vessels themselves controlled and stabilized, they'll probably let them sit for 5 to 10 years until they really go in and start doing lots of cleanup. They'll send robots in to go in and see what's wrong. But they're not gonna be able to do a lot until it really -- a lot of the radiation decays away. On the spent fuel pools, they're gonna -- I would say in the next year -- in the next several months generate a plan to try to seal the loose contamination around or into the pool. And you've heard talk of the Chernobyl solution of pureeing concrete or sand into it. That's the only place where that makes sense, is in the spent fuel pools when you're trying to seal in that contamination in those particles. So we may see them do something like that.
CAVANAUGH: Doctor Murray Jennex, thank you so much for speaking with us again.
JENNEX: No problem. I enjoyed it.
CAVANAUGH: Doctor Murray Jennex, associate professor at SDSU. If you'd like to comment, please go on-line, KPBS.org/These Days. If up next, we have more on the Fukushima earthquake as it affects the culture of Japan. That's next as These Days continues here on KPBS.
To view PDF documents, Download Acrobat Reader.