FUKUSHIMA DAIICHI NUCLEAR POWER PLANT UPDATE
The following presentation was delivered at the 81st General Meeting on May 14, 2012, by Kenneth R. Balkey. It has been edited for content and phrasing. Mr. Balkey’s accompanying slide presentation can be viewed here.
On March 11, 2011, the world watched in horror as events unfolded at the Fukushima Daiichi Nuclear Power Plant in Japan. Much has happened since. Kenneth R. Balkey, member of the ASME Presidential Task Force on response to Japan’s nuclear power plant event, provides insight on both the events and aftermath of Fukushima.
Mr. Balkey is senior vice president for ASME Standards and Certification and chair of the ASME Council on Standards and Certification. As an ASME fellow, there is probably no one in this room who has a better grasp on both the events and aftermath of Fukushima.
Mr. Balkey is a consulting engineer with Westinghouse Electric Company in Pittsburgh, who has accumulated nearly 40 years in the nuclear power industry. As a senior consulting engineer, he provides consultation and advises on developments and technology related to codes and standards and risk management initiatives. A professional engineer, Mr. Balkey earned both his B.S. and M.S. degrees in mechanical engineering from the University of Pittsburgh where he currently serves as an adjunct faculty member.
Mr. Balkey has more than 140 publications and documents to his name. Additionally, he holds two patents related to reactor pressure vessel integrity and risk-informed inspection of heat exchangers. Mr. Balkey is the recipient of numerous honors, including ASME's Dedicated Service Award, the Bernard F. Langer Nuclear Codes and Standards Award, and the Melvin R. Green Codes and Standards Medal.
Thank you very much. I'm honored to speak here at the 81st National Board/ASME General Meeting on a very challenging topic. I listened with great interest to Mr. Toler on the events that occurred in Texas in 1937. I almost feel as though here we are 75 years later, a different type of event, but we are facing some very difficult decisions as a result of the event that occurred, and it is going to determine what we do and how we go forward from here, and what other advances have to be made, just as was done with putting odorant in gas to save lives.
Today I will share an update on Fukushima and what ASME has done since March 11, 2011, in working with our colleagues in Japan and many other people from around the world dealing with this very challenging event.
(Slide 3) First I’ll give an overview of what happened back in March of 2011. And I’ll share two of ASME’s efforts. One started immediately after the event and deals with how our nuclear codes and standards could be impacted and how we respond to severe accidents that occur. And second, shortly after the event, ASME President Victoria Rockwell formed a Presidential Task Force over the summer led by two distinguished individuals, Dr. Nils Diaz, past chairman of the Nuclear Regulatory Commission, and Dr. Regis Matzie, who is prior senior vice president and chief technology officer for Westinghouse. Both of these gentlemen are world recognized in the nuclear field.
When I was asked to give this talk, I didn’t think we would be at a point to release our report, but we are just about ready to release it. You are the first public audience to hear our recommendations.
(Slide 4) There is a lot of focus on Fukushima Daiichi, but on that very difficult day on March 11, 2011, four nuclear power stations were greatly challenged. The Onagawa plant was actually closer to the epicenter than Fukushima Daiichi. Daiichi is about ten kilometers (or six miles) north of Fukushima Daini. Daiichi means Station 1 and Daini means 2. So you have six reactors at Daiichi, four reactors at Daini, and three reactors at Onagawa. And south of Fukushima is Tokai, where more reactors were operating.
As this event occurred – this is the fourth largest earthquake ever to strike the earth – it was followed up shortly after by enormous tsunami waves. All 14 reactors had to respond to that event, and Fukushima was the reactor site that was overwhelmed with the tsunamis, more so than the other reactor sites.
(Slide 5) At Fukushima Daiichi, Unit 1 went into operation in 1971. Unit 4 went in around 1976 or '77. Units 5 and 6 are a little bit higher above the ocean than Units 1-4, and they came into operation in the late 1970s. The reactors run from north to south, from Unit 1 down to Unit 4.
(Slide 6) As I talk about the events, I will be talking about the different reactors and the state of what happened. This is a picture of one of the first tsunami waves to come in. The earthquake struck around 2:45 on a Friday afternoon, and within 45 or 50 minutes, these enormous waves started striking at the Japan coast for over 400 miles. So it was more than just a local effort. This was an entire nation being struck by massive waves. And the waves didn’t come like a surfer's wave. It's as if the water rose out of the ocean onto the site.
(Slide 7) These are actual pictures from the Fukushima site. The buildings are three or four stories tall and were struck by waves of that height. And they didn't just come in once. The waves came in as many as six or seven times; the water kept rushing up against the site.
The waves did strike the station a number of times. The tall buildings were the reactor buildings and the turbine generator buildings were the closest to the ocean. And you can see how high the water came up around that turbine generator building.
(Slide 8) In fact, you can see a sport utility vehicle sitting vertically next to the building, to give you a sense of how significant the water level was. This is an unprecedented natural event that has never been seen anywhere.
The earthquake struck first and took out the power grid. All electrical lines were lost into the site. The top engineer from Tohoku Electric, who operates the Onagawa station, spoke at the University of Pittsburgh and said out of five power lines running into the site, they lost four. But fortunately they kept one, because they still had external power to keep some of the emergency equipment. But at Daiichi, they lost all power.
(Slide 9) The water level came up several times surrounding the turbine building and the diesel generators, which kicked on at all 14 sites when the earthquake struck. All reactors were scrammed. Those that were operating scrammed appropriately, and the diesel generators came on to provide backup power to keep the emergency equipment running and the core cool.
When you shut down a reactor, there is a tremendous amount of decayed heat that has to be removed in order to keep fuel from melting. And if you lose the delivery of emergency water to the reactor, the fuel will start to melt. That's what happened at the Daiichi site on Units 1, 2, and 4 that were operating. Unit 5 was shut down for a major component change out, but there was still damage to that reactor.
So they had a loss of power from the earthquake. The tsunami wave comes up, wipes out all the diesel generators, floods out, and even floods out the batteries. As backup at nuclear power plants, in addition to the diesel generators, there are batteries in place to keep the emergency equipment running for at least eight hours.
The diesel generators became inoperable due to the tsunami floods. When you lose your power lines and diesel generators, you are in a very difficult situation called a station blackout. All motor-operated pumps, including the emergency core cooling system, became inoperable.
There were batteries on site, but the challenge was that this event lasted for many hours; in fact, it went on for a few days, and they couldn't get any external power to the site because there was so much damage to the roads and other infrastructure.
(Slide 10) Here is a picture of the reactor building at Fukushima Daiichi. The fuel rods are inserted from the bottom into the vessel. There is a primary containment structure. When they lost the diesel generators and didn't have the batteries (and the batteries they did have finally ran out) the core was sitting there, and at these three reactors (Units 1, 2, and 3 that had been operating and were shut down), the fuel began to melt.
And then, as steam was produced with the zircaloy tubes, it ended up generating a hydrogen gas. The gas seeped out of the reactor vessel probably through overpressure. Then it seeped out of primary containment, and the gas then leaked into these reactor buildings. And similar to Mr. Toler's discussion, a small spark is all it took to blow the reactor building at Units 1 and 3. And because of cross tide, gas had leaked into Unit 4 and blew that building as well.
Regarding Unit 2, Tokyo Electric Power was able to vent the gas out of the reactor building on Unit 2 and the Unit 2 reactor building did not blow, although the reactor itself did have fuel melt within it. With regards to the National Board of Pressure Vessel Inspectors, the state of the vessels is unknown at this point. They know that fuel has leaked out through the bottom of the three vessels and there is fuel on the bottom of the primary containment building. But in terms of the state of the vessels, it's unknown, and it's going to be some time (it could be several years), until we will know the state of the three vessels because of the radiation fields around the three reactors.
(Slide 11) There are ongoing recovery efforts. Of course, they ended up bringing in sea water once they could get equipment on the site and it has been keeping the reactors cool. They got the plants into cool shutdown back in December of 2011. It took almost nine months to get these three reactors in shape. In addition, cooling water has been used. There is a lot of spent fuel storage that's been at these sites. Unit 1 has been operating for over 40 years, so there is a lot of spent fuel stored on that station, and therefore they had to bring in measures to keep that fuel cool as well. And they have had to process radioactive water, because if they poured water into the vessel, it was an open system, so they had to bring in massive shipping containers that keep the radioactive fluid going from that case.
(Slide 12) These are pictures from Tokyo Electric's website. You can see looking south of Unit 4 as of April 16th. There is now a major effort to build a building over these buildings. The first step is to actually move spent fuel out of the Unit 4 reactor. And this view on the right side is looking north at the plant. So you can see there is enormous construction to get the spent fuel and then start getting equipment to dealing with the damaged fuel itself.
There have been estimates that the cleanup of this site is going to take anywhere from 30 to 40 years. That's a pretty significant time frame. And to put it in perspective, Three Mile Island (TMI) did not have any releases. There was fuel damage, but it was all kept within the reactor pressure vessel, and it took 14 years to clean up Three Mile Island. So this is a much bigger situation.
(Slide 13) What's been the impact? Four reactors are destroyed. One of the biggest impacts is that 100,000 people who lived within a 20-mile radius of the plant have been evacuated for over a year, and they don't know when and if they will be able to go back. There has been extensive land contamination. As of May 5th, every reactor in Japan is shut down. That hasn't happened since they started their industry more than 40 years ago. It's had a tremendous economic impact on Japan, and it has a huge impact on nuclear programs throughout the world.
(Slide 14) Japan has had to rely on a lot of fossil fuels to make up for some of the power. But they have had rolling blackouts in Tokyo and in other major cities last year, and the country is being braced for other energy curtailments going forward.
This has been a very difficult event, but you have to put it in context. Keep in mind 400 miles of coastline were struck, almost 16,000 people have lost their lives, another 3,000 are still missing, and there were over 26,000 people injured.
(Slide 15) And more than just nuclear power was impacted. It took out their thermal plants, their hydro, their oil refineries, and the electric power grid. Their transportation and manufacturing was taken out. 125,000 buildings were destroyed. More than 300,000 people essentially are serving as refugees, and there are huge challenges for food and water supply. My colleagues in Japan have told me that they deeply appreciated the U.S.A., particularly through our military, for getting food and supplies to the Japanese people following the event from our ships that were in the area.
And to recall our close relationship, there are 51 engineers from Japan who are actual contributing members to ASME's Standards and Certification programs, and we have over 600 engineers from Japan that are formal members of ASME as a professional society. So these are our own. We are all working together to address these issues.
(Slides 16/17) Regarding the Board of Nuclear Codes and Standards, right away we formed a task group not only to get an understanding of what standards may get impacted from the event, but the intent is to develop some data dissemination system on the damage that has resulted from the incident in each of the focus areas that are the design. Teams of experts have been pulled together and are still being put together on code impacts and identifying recommendations to the responsible committees. We have had to coordinate this effort with the new United States Nuclear Regulatory Commission, the Nuclear Energy Institute, other stakeholders (including other professional societies such as American Nuclear Society), and we clearly are communicating with other international stakeholders as well.
(Slide 18) There are four aspects of the event that the task force is studying. One is the design basis. We are dealing with an event that was well beyond what anybody would have imagined in terms of not just the size of the earthquake, but particularly the tsunami waves. And the other thing that's driving us: in 2011, for those of you from Nebraska, the Fort Calhoun Nuclear Station experienced the worst flood in 100 years that really challenged that plant. We had a tornado at the Browns Ferry Station in Alabama. And we had our own earthquake in North Anna – an earthquake that was beyond the design basis for North Anna. So this question of design basis for external events, while we are looking in Japan, we had other incidents occur in the U.S. that would give us the same challenge.
Next is component integrity. In terms of maintaining the pressure boundary when you have core damage events underway, it's a topic that is definitely going to be raised, as well as containment integrity. Another important aspect is the safety system response: dealing with a station blackout, controlling hydrogen, and spent fuel pools. And finally, there is the issue of severe accident mitigation consequences. In those four areas there will have to be significant standards work either in changing standards or even coming up with new standards for that effort.
(Slide 19) Now we’ll turn to the ASME BNCS Task Force. Bryan Erler, who finished serving as Vice President of ASME Nuclear Codes and Standards last June, has kindly agreed to chair this group. In fact, he's commuted to Japan several times to meet colleagues in the Japan Society of Mechanical Engineers (JSME). Partnered with him are Don Spellman from the American Nuclear Society, Stuart Richards from U.S. Nuclear Regulatory Commission, Alex Marion from NEI, and Dr. Masaki Morishita from JSME, who is here with us in Nashville. Dr. Masaki is the chair of JSME's Codes and Standards, so he's their most senior person. And Chris Sanna, who many of you know, is the staff member on this effort and has been commuting to Japan with Bryan.
(Slide 20) Right now the biggest effort is that the Japanese plants have come offline. In the United States, once our U.S. Nuclear Regulatory Commission gives approval to restart a plant, the plant can go into operation. But in Japan, the national government can give approval, but the local prefect or jurisdiction can prevent the plant from starting. And, in fact, as the Tomari plant was shutting down, that was the last operating reactor on May 5th, the Ohi Units 1 and 2, they are pressurized water reactors. The government has given approval for them to start, but the local prefecture has not. So there were hopes of getting these other two units up so they could help get the other units underway.
JSME put together severe accident management guidelines and asked for ASME's help, and my colleagues worked that effort pretty well. We are currently populating the subgroups. This is going to be a long-term effort as information becomes available from these events, and there have been several meetings in Japan, as I've mentioned, since that event occurred.
(Slide 21) The last one I want to leave with is the Presidential Task Force that I have the honor of serving as a member with Dr. Diaz and Mr. Matzie. This is a slide presentation from Dr. Diaz’s presentation at the Nuclear Regulatory Commission's Regulatory Information Conference back in the middle of March, and that was when ASME first announced its recommendations.
We have already done the peer review, and it's going through the last technical editing right now. But the thrust of our recommendation is a very bold statement by ASME – it's the need to forge a new nuclear safety construct as a result of this event.
(Slide 22) We were chartered by President Rockwell to look at what happened, but also at what's happened over the last 50 years of nuclear power plant operations. We spent significant time reviewing history, not just of nuclear, but other high-hazard industries including the pressure technology industry and the airline industry. We reviewed the events at Fukushima Daiichi, but we also looked at the other reactors in Japan that were impacted. And we are defining what ASME's role should be going forward and the best way to disseminate our perspective on this very difficult challenge.
(Slide 23) These are the members of the group. I won't go through everybody, but let me just say that Jack Devine was at GPU at Three Mile Island, and Roger Mattson was on the NRC staff at Three Mile Island, and Roger also was at Chernobyl. So there are several people on the group who were intimately involved with the prior events at TMI and Chernobyl, including Dr. Diaz himself.
(Slide 24) Our main deliverable is a comprehensive report summarizing our findings and recommendations. And at the time I put these slides in, the peer review was underway. We had reviewers from around the world and from all the top agencies here in the U.S., as well as some key utility executives. And we are outlining our next actions, which I will talk about.
ASME has the ability to be a convener and bring people from all the different stakeholders together to discuss how we forge this new safety construct going forward. We are working with ASME's public information and communications staff to disseminate these results in many different forums, including going publicly and even possibly in the media.
(Slide 25) The areas we addressed in our report, as I’ve mentioned, were historical safety perspective on the reactor industry, but also other major industries as well. We spent time on what we call going beyond the design basis and providing adequate protection for these rare, incredible events that can still happen, such as what happened at Fukushima Daiichi. In fact, Fukushima Daiichi was the first reactor to have an accident due to an external event. TMI was from internal events, and Chernobyl also was from internal events from reactor operation errors. But all these events have human error and human performance both on individuals as well as through organizations, and we spent some time going through not just Fukushima, but the other events too, to talk about the human performance.
I think those of you in the pressure technology industry relate to that very well. But then, how do you deal with accident management and emergency preparedness? Even though it was a difficult decision, the Japanese did move those 100,000 people, and nobody has been affected by the radiological effects from the event. So they were able to move and mobilize people. It was a very, very difficult situation. But some other supporting activities are really key to us here.
There has been a loss of public trust. In fact, our report has a chart. In the United States, the public confidence was a little bit less, and it's actually come back. I had the opportunity to meet with the president of JSME back in December, and he said not only has the Japanese public lost faith in nuclear power, they have lost faith in science and technology because of the tremendous impact not just to the nuclear industry but to all the other infrastructure that support their nation. And it will take some very significant work to help rebuild that trust. And in Europe trust was lost in a number of countries. As you know, Germany is in the process of shutting down all of their plants.
(Slides 26/27) And then we talk about updating the standards and the lessons learned. What did we learn from these three accidents at TMI, Chernobyl, and Fukushima Daiichi? One is that the radiological public health consequences for the most part were managed with no prompt fatalities and minimal delayed public health effects. And the very significant consequences are the same as I had on the other slide: the radiological contamination of a populated area in Japan; relocating 100,000 people; impact on economic productivity; the curtailing of nuclear power in Japan and other countries; and a very substantial economic impact yet to be determined, although we do make an estimate of that effort.
(Slide 28) The key lessons that come out of this are that all of our regulations are set on protecting public health and safety from radiological releases. That's been the fundamental core. And what we are saying is that protecting public health and safety from radiological releases is not the major consequences of these events. The true consequences have been the socio-political and the enormous economic disruptions inflicted on society at an enormous cost. That's been the greater challenge.
An accident resulting in a large uncontrolled release of radioactivity disrupts the socio-economic fabric of society, including permanent displacement of large people, large economic costs, and it results in an unacceptable outcome. In some ways, the Deep Water Horizon event had a similar effect where we had loss of life on the platform itself, but the economic disruption and environmental impact was significant and impacts other energy decisions. So what we are proposing is that there is an emerging safety construct coming about, and what this picture tries to show is that when we built the existing fleet of new plants, there was a design basis very well thought out, a lot of margin, that goes back over 50 years.
(Slide 29) After the 9-11 terrorist attacks, nuclear plants were beefed up with additional equipment and additional procedures. But those features were not incorporated across the world. Some nations have, but some have not. And what's emerging now out of Fukushima Daiichi is the aspect of having portable equipment in a place that would not be impacted. You could bring it in. There would be portable equipment on site, but also regional centers set up so you could get equipment from other places and bring it in very close. There is work being done by the Nuclear Energy Institute, the Nuclear Regulatory Commission and many other countries, but ASME is saying that all these efforts need to go under one umbrella. We are trying to forge a new nuclear safety construct that, in addition to providing protection of public health and safety, will also work to not have these releases and cause this social and economic disruption.
(Slide 30) Next are some key elements we provide. The Nuclear Regulatory Commission report on the AP1000 has indicated all these extra features already built in through the passive design. The new plants being built in China, Georgia, and South Carolina actually have most of these measures already incorporated.
(Slide 31) So finally, in looking to the future, why are we doing this? It’s because nuclear power is desperately needed around the world. It is by far the largest generation of electricity with no environmental impact, meaning we are not putting anything into the atmosphere during normal operation of a plant. We have 7 billion people on the planet today, heading to 9 billion by 2050. All of us are using more energy than what we did before, and we need to be able to sustain our way of life going forward, not just in the developed countries, but in the developing countries as well. So it's the largest provider of steady, base-load, emission-free electricity with the smallest footprint as compared to similar sources.
ASME’s recommendation proposes forging a new nuclear safety construct to ensure nuclear power can be utilized in a safe, environmentally sound manner going for many, many years into the future to meet this enormous global challenge.