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UNION OF CONCERNED SCIENTISTS UPDATE ON JAPAN'S NUCLEAR POWER CRISIS

UCS MEMBER PHONE CONFERENCE
MARCH 18, 2011, 3:30 P.M.


OPERATOR: Ladies and gentlemen, welcome to the Union of Concerned Scientists conference call. At this time, all participants are in listen-only mode. Later, we will conduct a question-and-answer session, and instructions will be given at that time. If you should require assistance in today's conference, please press star, then zero, on your touchtone telephone. As a reminder, the conference call is being recorded. I would like to introduce your cohost for today, Ms. Lisbeth Gronlund. Ma'am, you may begin.

DR. GRONLUND: Thank you, and thanks to all of you for joining our call this afternoon. We know there has been a great deal of interest in the unfolding events in Japan, and I am pleased that we are able to talk to you today about the technical and safety issues and potential impacts of the damage to the reactors.

USC has been a nuclear power safety and security watchdog for over 40 years, and we have been called on this week to provide reporters and members of the public information about the ongoing events in Japan. Frankly, we have been drinking out of a fire hose. We are now doing daily press briefings at which we have about 100 reporters each day. Our experts have made numerous appearances on news shows and radio shows. We're updating our website as fast as we can and providing background information and materials for people to understand what is happening and what it might mean. On our call today, we have our two nuclear power experts who are going to be available. They will make a statement and then they will be available for Q&A. I am very pleased to introduce Dave Lochbaum, who is Director of our Nuclear Safety Project. Dave is one of the nation's top independent experts on nuclear power. He spent 17 years working in the nuclear power industry, and he actually has worked at three reactors similar to the ones in Japan. At UCS, he monitors safety issues; he raises concerns with the Nuclear Regulatory Commission, or the NRC; and he responds to breaking events, such as this one. He recently spent a year at the NRC training nuclear engineers on safety issues. Also on the line is Ed Lyman, Senior Scientist in our Global Security Program. His research focuses on the prevention of nuclear proliferation and nuclear terrorism. He's an expert on nuclear plant design and environmental and health effects of nuclear radiation. Ed has a Ph.D. in physics from Cornell University. He has testified before Congress and the Nuclear Regulatory Commission; served as an expert witness for interveners in several NRC licensing proceedings; and on Wednesday, he briefed the Senate Committee on Environmental and Public Works on the situation in Japan and its implications for U.S. nuclear power. Dave and Ed -- actually, Ed and Dave -- Ed is going to start by giving you an overview of the situation in Japan, and then Dave will discuss the implications for nuclear power in the United States. Ed, go ahead.

DR. LYMAN: Thank you, Lisbeth. I'll just give a brief overview of how things got to where they are and where we are right now as far as we know it, and I'll be happy to take your questions. This accident was precipitated by an earthquake, followed by a tsunami, that led to the complete loss of power to a nuclear power station, the Fukushima Dai-Ichi Station in Northern Japan. When nuclear power plants lose all their power, which means access to off-site power and also the failure of on-site emergency power, that is a very serious situation, because nuclear power plants, even though they generate electricity, actually need to take electricity from somewhere else to operate their cooling systems.

This resulted in the plant's being dependent on a single remaining cooling system that operated on battery power, which had life of eight hours, and at least -- well, it wasn't clear even if that cooling system was functioning well even on batteries, but certainly as time went on, those systems were lost, and then the cores of each of the three reactors, 1 through 3, started to lose cooling. This is a very serious situation, because in a nuclear reactor, even after it's shut down, it continues to generate heat for quite some time, several weeks or longer, at which it requires a considerable effort to remove the decay heat from radioactive fission products, and if you don't take that heat away fast enough, the fuel can overheat, get damaged, and eventually melt, releasing much of its radiation.

Now, these reactors have several barriers between the core and the environment. The first barrier is the fuel itself. Undamaged fuel is in the form of rods, and they are surrounded by metal tubes made out of zirconium. The entire nuclear core is then in a reactor vessel, which is several inches of steel, and that whole assembly is then put within a primary containment structure, which is a thin metal, leak-resistant structure surrounded by concrete. Then all of that is then in a concrete reactor building.

So, in order for a large radiological release to occur to the environment, several things have to happen: Fuel has to get damaged so the zirconium cladding gets ruptured; the reactor vessel needs to be significantly breached; and the containment also needs to be breached.

The status of these three reactors is that it is now believed that the containment is breached in Number 2 and possibly also Number 3; there's fuel damage in all three reactors to varying extents, which are not fully clear; and in all three of those reactors, hydrogen explosions took place. Hydrogen is generated when that zirconium cladding I talked about starts reacting with water vapor and produces hydrogen gas, which is potentially explosive, and in two of the cases, the hydrogen explosions destroyed the external reactor building, which is not the most robust part of the structure in any event. So, it's not a surprise that that could be actually destroyed by a hydrogen explosion, but nonetheless, it's a serious event that occurred. And number two, there may have been an explosion within the containment that caused a breach of that containment.

Now, there are three other reactors on-site, 4 through 6. They were all shut down at the time of the accident; however, that doesn't mean that we're out of danger, because the spent fuel from those reactors was in the spent fuel pools, which in this type of reactor design, sit on top of the -- actually above where the reactor is. So, there are actually six spent fuel pools, each reactor has one, and those also require active cooling to prevent the potential for an overheating of the fuel and possible release of radiation from that fuel as well.

The current status is that at least two of the spent fuel pools are known to be in some difficulty, Numbers 3 and 4, where there have been reports that they have had significant loss of water. Those reports are very sketchy, contradictory. On Wednesday, the Chairman of the U.S. Nuclear Regulatory Commission, Greg Jaczko, said that the pool in Unit 4 had boiled dry, but the Japanese contradicted him and then subsequently said they actually saw water in the pool from the helicopter.

But this just underscores the fact that there's really a complete lack of information. Even the authorities there are unable to really know what's going on because of the conditions. They've had to repeatedly vent radiation from the Reactors 1, 2, and 3 themselves to relieve pressure so that they can continue to get coolant in. I should say that right now, those reactors are being kept from getting any worse through the constant injection of seawater, which is a last-ditch measure to try to keep the cores cool enough so that they don't melt down any more than they are.

The Japanese are also engaged in an attempt to keep the spent fuel pools from boiling dry. They have been trying to drop water out of helicopters, trying to pour it in using a police water canon. All of the reports indicate that none of those efforts are successful. In fact, just looking at the numbers, it's hard to imagine that they could keep the water level from decreasing through the amount of water they're able to put in through those methods, even if they were fully successful.

So, there are a couple of other measures that have been attempted. They finally were able to connect off-site power again to the site and to at least one reactor. I haven't heard the latest status, but there's some question whether, even if they do that, if the original pumps are still functional, given the fact that there were hydrogen explosions and they may have been damaged by the previous earthquake. So, the status is still not clear, whether the situation can be stabilized, and in the meantime, radiation continues to be released from the site.

The French safety authority, called IRSN, just put out a statement saying that the releases already equal 10 percent of the release that came from Chernobyl. My own assessment is I think that's reasonable, and that's typical of the release before there's actually extensive damage to the fuel. So, what they're signaling is that there hasn't been extensive fuel damage that's already gotten out into the environment yet, meaning from the actual solid part of the fuel itself, and if there were to be further damage and melting of the fuel, that the
releases could still increase probably by a factor of ten or more.

There has been radiation detected now in San Francisco, but one has to understand that the radiation monitors are extremely sensitive, and they're detecting very, very low levels of radiation, and in our judgment, this accident is not going to pose a major health threat to Americans. It will likely pose a severe health threat to the Japanese. And I guess I'll stop there.

Do you think I skipped anything important, Lisbeth?

MS. GRONLUND: No, and I think anything else will come up in questions and answers.

DR. LYMAN: Okay.

MS. GRONLUND: Dave?

MR. LOCHBAUM: Good afternoon. Thank you for taking time out of your day to participate in this call. I want to touch upon two things to supplement the fine summary that Ed just provided, and that's dealing with how the events that occurred in Japan happen in the United States.

The reactors in Japan, three of the reactors are General Electric designs. They're American technology, similar designs, under similar regulations. So, if faced with a similar situation in the United States, it's reasonable to assume that a similar outcome might occur.

The real problem that was faced in Japan or the primary problem that was faced in Japan, as Ed explained, was the extended loss of power. The earthquake knocked out the normal supply of power from the electrical grid, and then the tsunami took away the backup supply of power, which was the emergency diesel generators, and that left the plant with just a minimal, bare-bones set of equipment that got power from the batteries.

As Ed indicated, Japan's batteries at that reactor, they were designed to last for eight hours. If you look at the United States, with the 104 reactors that we have, 93 of those reactors only have four hours of battery backup; 11 of the reactors have eight hours of battery backup. When events don't follow the scripts and last longer than we think they will last, we could be in the same kind of situation that Japan faces right now. So, that is a problem, and I think one of the lessons learned from this accident will be to revisit those power backups and see if we need to make adjustments so that our plants will be less vulnerable in that kind of a situation.

In addition, even though our plants -- some, like the plant in Kansas, isn't really susceptible to an earthquake/tsunami, a one-two punch, our plants are designed in places where we can have station blackout loss of power. The West Coast has earthquakes; the Gulf Coast and Florida has hurricanes; the Midwest has tornados; and the Northeast has ice storms and northeasters.

In addition, one of our plants in Georgia has already had a station blackout event. That plant was in a refuelling outage when one of the company trucks backed into a transmission line in a switch yard and knocked out the electrical power from the grid, and the emergency diesel generators started up but failed due to a faulty switch. So, the only power they had was batteries. Fortunately, they were able to restore or fix the emergency diesel generator before the batteries were depleted. In 1999, the Indian Point plant outside of New York City faced a situation where they were disconnected from the electrical grid due to a breaker fault. The emergency diesel generators were started up. Some of them were working; some of them were not. The batteries were eight-hour battery capacity, but they didn't get the problem fixed in less than eight hours. They lost about half of the power to the plant, but fortunately, the remaining half was able to prevent the meltdown. But they took many steps down that road and fortunately found a detour before the bad destination. The other half is from the dire problem they're facing right now, and that's the spent fuel pools. Spent fuel pool problems at this type of reactor is the reason I'm at UCS. When I was working at the Susquehanna plant in Upstate Northeastern Pennsylvania back in 1992, a colleague and I found a problem with how the cooling for these plants were done. The spent fuel pools, the only source of power for the systems that cool the spent fuel pools is that that's provided from the electrical grid. If the electrical grid is not available, they are not supplied power from the emergency diesel generators, and they're not supplied power from the batteries. So, we said, well, what happens if you have a -- you lose the electrical grid and power lasts -- is out for quite a while? You have no way to cool the pool. As Japan has shown, that pool is located in a reactor building that's not four feet thick of concrete. It's in a relatively less robust building. In that case, the hydrogen explosion destroyed the building. I've worked at a plant in Browns Ferry where high winds ripped the metal siding off the building. It's a lot of material. Often, the spent fuel pools have much more fuel than is in the reactor core, and it's located in a place that doesn't have all the elaborate safety and backup systems that the core is provided with. And further, it's located in a building that's not as effective a barrier should fuel damage occur, as is provided for the reactor core. So, it's an equally or greater hazard without the benefits or without the protective devices that the reactor core is provided. So, it's really not a surprise that Japan's biggest problem is its greatest hazard, the spent fuel pools. When the colleague and I raised that issue, the company didn't want to fix it. We ended up going to the Nuclear Regulatory Commission thinking that we were calling in the cavalry, but instead, Laurel & Hardy showed up.

So, that led me down a path, when the UCS job came open, I was fortunate enough to be selected for that job and work on safety issues from that platform. Unfortunately, we weren't able to fix that problem before it manifested itself in Japan, but hopefully, we'll be able to translate the fixes from that to our U.S. plants. The easiest fix and one that can be accomplished relatively quickly -- if my voice holds out -- is to lessen the amount of fuel that's stored in the spent fuel pools. We can accelerate the transfer of spent fuel from the pools into dry casks, which are still stored on-site, but they're in more robust containers. By doing that, the remaining fuel in the spent fuel pools can be spread out, kind of like spreading out logs on a campfire, reducing the heat load, the combined heat load, and that will give workers more time to deal with a loss of water or loss of cooling, which greatly increases their likelihood of being successful in those endeavors.

And if they fail for whatever reason, because you have less spent fuel in the spent fuel pools, the size of the radioactive cloud that's emitted is much, much less. So, from both a security standpoint and a safety standpoint, that's a no-brainer. But so far, those are measures we haven't yet taken. Thanks.

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