Friday, September 30, 2011

Safety Problems in all Reactors Designed Like Fukushima

Fairewinds Introduces a Japanese Language Edition and Identifies Safety Problems in all Reactors Designed Like Fukushima

Fairewinds Introduces a Japanese Language Edition and Identifies Safety Problems in all Reactors Designed Like Fukushima from Fairewinds Associates on Vimeo.

Gundersen expresses concerns that the nuclear industry and the Nuclear Regulatory Commission are not addressing major safety issues that have become evident since Fukushima. These issues include serious design flaws in the BWR Mark 1 containment, fundamental flaws in the Boiling Water Reactor vessel design, and problems with detonation shockwaves. The NRC and the nuclear industry are using a flawed cost benefit computer code that underestimates the value of human life and minimize property damages after an accident, which has the effect of justifying continued operation of reactors without safety modifications.

Also, Fairewinds announces the launch of the Japanese language version of its site,


Hi. I'm Arnie Gundersen from Fairewinds.

It's been about three weeks since we posted a video, although there have been a couple radio interviews posted. That doesn't mean we haven't been busy here at Fairewinds. I have been doing expert witness testimony but more importantly Maggie and Kevin Hurley have been busy converting to which will be a Japanese translation of our website. I’d like to thank a large number of dedicated Japanese speakers who have worked with us in translating all these videos into Japanese. Today is the first day that and will be broadcasting the same material. Thank you very much to those volunteers.

In the last several months the Nuclear Regulatory Commission (NRC) issued a review of safety as a result of the Fukushima accident. They just published their report in several key areas that they wanted to look at in more depth. That report is on our website but more importantly the Union of Concerned Scientists, acting as a watchdog over the NRC, has issued a critique of that initial nuclear regulatory report. We posted that Union of Concerned Scientists critique as well, and there are important lessons that the NRC has identified but more importantly there are issues that the Union of Concerned Scientists have recognized where the NRC needs to really put their money where their mouth is and not just study safety issues but actually implement safety changes.

Well today what I would like to talk about are four things that are not in the NRC 's report that I really think should be in the NRC's report. They are the containment, the reactor, the explosion and the last thing called Severe Accident Mitigation Analysis. The first thing is the containment on this boiling water reactor and the 35 other boiling water nuclear reactors that are exactly like that. Back in February, about three weeks before the accident, Maggie and I were walking and Maggie said, “You know we are doing a lot of expert reports and we are finding a lot of problems,” and she asked me, “Where do you think the next accident will occur?” I said I don't know where but I know for sure it will be in a Mark 1 boiling water containment. Well that's what the Fukushima reactors were: Mark 1 containments. This picture of a boiling water container was taken in the 70's. This is identical to the Fukushima reactors. Let me walk you through this.

There's two pieces to the containment, the top looks like an upside down light bulb and that's called a drywell. Inside there is where the nuclear reactor is. Down below is a doughnut looking thing called a torus and that's filled almost all the way with water. The theory is that if the reactor breaks steam will shoot out through the light bulb into the doughnut creating lots of bubbles which will reduce the pressure. This thing is called the pressure suppression containment. At the bottom of that picture is the lid to the containment. When it's fully assembled that lid sits on top.
The containment is about 1 inch thick. Inside it is the nuclear reactor that is about 8 inches thick. We will get to that in a minute. This type of containment was designed in the early 70's, late 60's, and by 1972 a lot of people had concerns with the containment. I want to read to you a NRC memo from 1972 that talks about the problems of this pressure suppression containment:

"Steve's idea to ban the pressure suppression containment scheme is an attractive one. However, the acceptance of the pressure suppression containment system by all elements of the nuclear field including regulatory and the advisory committees on reactor safeguards is firmly embedded in conventional wisdom. Reversal of this hallowed policy, especially in this time could well lead to the end of nuclear power. It would throw into question the operation of licensed plants and it would generally create more turmoil than I can stand."

So in the early 70's the NRC recognized this containment system was flawed. In the mid-70's they realized the forces were in the wrong direction: instead of down they were up, and large straps were put into place. Well then in the 80's there was another problem that developed. After the Three Mile Island [accident], they realized this containment could explode from a hydrogen build up. That had not been factored into the design in the 70's, either. What they came up for this containment was a vent in the side of it. The vent is designed to let the pressure out and a containment is designed to keep the pressure in.
So, rather than contain this radioactivity engineers realized if the containment were to survive an explosion, they'd have to open a hole in the side of it called a containment vent. These vents were added in the late 1980's and they were not added because the NRC demanded it, what the industry did to avoid that [demand] was to create an initiative. They put them in voluntarily. That sounds really in fact very proactive, but in fact it wasn't. If the NRC [had] required it, it would have opened up the license on these plants to citizens and scientists that had concerns. By having the industry voluntarily put these vents in it did two things. One, it did not allow any public participation in the process to see if they were safe and the second thing is it did not allow the NRC to look at these vents and say that they were safety related, in fact, it sidetracked the process entirely.

These vents were never tested until Fukushima. This containment was never tested until Fukushima. In fact it failed three times out of three tries. In retrospect, we shouldn’t be surprised.

Looking at the procedures for opening these vents in the event electricity fails requires someone fully clad in radiation gear to go down to an enormous valve in the bowels of plant and turn the crank two hundred (200) times to open it. Now, can you imagine: in the middle of a nuclear accident, with steam, and explosions, and radiation, expecting an employee to go into the plant and turn a valve two hundred times to open it? So, that was the second band-aid fix that failed on a containment that, forty years earlier, was designed too small.

Well, with all this in mind, I think we really need to ask the question: should the Mark 1 containment even be allowed to continue to operate? The NRC’s position is, “Well, we can make the vents stronger.” I don’t think that’s a good idea.

Now, all those issues that I just talked about are related to the Mark 1 containment. The next thing I’d like to talk about is the reactor that sits inside that containment. So, that light bulb and that doughnut are the containment structure. Inside that is where the nuclear reactor is. On a boiling water reactor, the nuclear control rods come in at the bottom. On a pressurized water reactor they come in from the top. All of the reactors at Fukushima, and 35 in the world with this design, come in from the bottom. That poses a unique problem and an important difference that the NRC is not looking at right now. If the core melts in a pressurized water reactor there are no holes in the bottom of the nuclear reactor. It’s a very thick eight to ten inch (8-10 Inch) piece of metal that the nuclear reactor core would have to melt through. But that didn’t happen at Fukushima. Fukushima was a boiling water reactor. It’s got holes in the bottom. When the nuclear core lies on the bottom of a boiling water reactor like Fukushima, or the ones in the U.S., or others in Japan, it’s easier for the core to melt through because of those sixty (60) holes in the bottom of the reactor. It doesn’t have to melt through eight inches of steel. It just has to melt through a very thin-walled pipe and scoot out the hole in the bottom of the nuclear reactor.

I’m not the only one to recognize that holes at the bottom of a boiling water reactor are a problem. Last week an email came out that was written by the Nuclear Regulatory Commission right after the Fukushima accident where they recognized that, if there’s a core meltdown and it’s now lying as a blob on the bottom of the nuclear reactor, these holes in the bottom of the reactor form channels through which the hot molted fuel can get out a lot easier and a lot quicker than a thick pressurized water reactor design. This is a flaw in any boiling water reactor, and the Nuclear Regulatory is not recognizing that the likelihood of melting through a boiling water reactor like Fukushima is a lot more significant than the likelihood of melting through a pressurized water reactor.

The third area is an area we’ve discussed in depth in a previous video. That area is that the explosion at Unit 3 was a detonation, not a deflagration. It has to do with the speed of the shockwave. The shockwave at Unit 3 traveled faster than the speed of sound, and that’s an important distinction that the Nuclear Regulatory Commission, and the entire nuclear industry is not looking at. A containment can’t withstand a shockwave that travels faster than the speed of sound, yet all containments are designed assuming that doesn’t happen. At Fukushima [Unit] 3, it happened. We need to understand how it happened and mitigate against it in the future on all reactors. Now, I measured that. A scale the size of the building against the speed at which the explosion occurred, and determined that that shockwave traveled at around a thousand miles per hour. The speed of sound is around six hundred feet per second (600 ft/sec) so, if this is what I think it is, it could cause enormous damage to a containment. They are not designed to handle it. Yet, the NRC is not looking at that.

So, we’ve got three key areas where the NRC and the nuclear industry don’t want people to look, and [those are, one]: should this Mark 1 containment even be allowed to operate? Two: are boiling water reactors more prone to a melt-through than a pressurized water reactor? And the third is: can containments withstand a detonation shockwave?

If the nuclear industry wants to implement a safety change, they have to do something called a cost-benefit analysis. What that means is the cost to implement the change has to be exceeded by the benefits to society if the change is made. This brings me to the last point today which is called “SAMA,” S, A, M, A. It stands for Severe Accident Mitigation Analysis. It uses a really fancy computer code that calculates exactly what the costs are to society in the event of a big accident. Those costs are in terms of human life, and they’re in terms of damages to property. The computer code is wrong. It’s been known to have been wrong for a long time, but it continues to be in use. The Nuclear Regulatory Commission puts the lowest possible value on a human life of any of the agencies in Washington. And, the cleanup after an accident is also artificially low. The net effect is that when a cost to make a modification is compared against the benefits to society, this computer code distorts the benefits and lowers them. So, it appears that there’s no need to make the change because the costs are too high and the benefits to you and I, and society, are too low. Fukushima has taught us that that’s just not true. The costs to clean up Fukushima are going to be in the hundreds of billions of dollars U.S. [The costs will be] at least two hundred billion dollars U.S. And yet, this computer code that the Nuclear Regulatory Commission uses never, ever, calculates a high number like that. Unless we adjust the cost/benefit analysis, what will happen is: as the Nuclear Regulatory Commission identifies problems that should be corrected, their own computer code will show that it’s not justified, that the risks to society are really too low, that we don’t need to spend that money. The problem is in the computer code, and until we upwardly adjust the cost of a human life, and the cost of damage to property we won’t be able to come up with an effective way of judging the costs and the benefits of these safety modifications.

Well, that about sums it up. There are at least three key areas that the Nuclear Regulatory Commission and the nuclear industry, both in Japan and the United States, are not looking at: containment design, boiling water reactor vessels, and detonation shockwaves. But, no matter what they look at, if they don’t do the cost/benefit analysis right and properly evaluate the cost to society, none of these changes will be implemented.

Again, I’d like to thank our Japanese viewers and welcome them to, and also to thank all of our viewers over the last one hundred and seventy days, and thank them for watching

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