Nuclear Containment Risk

During the 1960s when the American Advisory Committee on Reactor Safeguards debated containment structures, some members argued for the need to make stronger containments. Regrettably, a majority of the members believed that the emergency core cooling systems were adequate, so more than 50 years ago the Advisory Committee ignored its minority members and pushed ahead without rigorous failure-proof containment structures and systems. The Nuclear Regulatory Committee made the decision not to require stronger containments. Japan followed the American lead

In our most recent video, Fairewinds’ chief nuclear engineer Arnie Gundersen introduces us to the containment structures deemed adequate and strong enough by the NRC to protect civilians from nuclear meltdown. How could five radiation barriers fail at Fukushima Daiichi? Using the childhood game of dominoes, each domino represents a failed radiation barrier and like the game when a domino falls all others follow. Nuclear containment risk is nuclear power's fifth domino. Nuclear site failures are not a game and public safety is not something to play with- so why does the NRC act like a group of kids putting us all at RISK?



Hi, I’m Arnie Gundersen with Fairewinds Energy Education. Today I would like to talk to you about all the nuclear power plant protection systems that supposedly exist to keep radiation from escaping during nuclear plant emergencies. Recent scientific studies from Japan show that 75% of the radiation created by the meltdowns was released more than 5 days after the catastrophe, while only 25% of the radiation was released during the first 4 days. This data, which is posted on the website, shows that the total gaseous and liquid radioactive releases from the Fukushima Daiichi meltdown exceed the radiation released during and after the Chernobyl meltdown, while Fukushima Daiichi radioactivity continues to bleed into the Pacific Ocean. How then can so much radiation possibly penetrate all the radiation barriers engineers designed for nuclear power’s safe operation? When I received my bachelor and master degree in nuclear engineering, nuclear engineers were taught that there are at least 6 barriers that protected us from massive radiation releases during and following nuclear emergencies. Lets look at these radiation release barriers: 1. The first barrier designed by the nuclear industry is supposed to be the fuel pellet itself. It is ceramic and is designed to hold radiation inside. 2. The second radiation protection barrier is supposed to be the zirconium alloy fuel cladding that is designed to contain what is anticipated to be a small amount of radiation that would escape from destroyed fuel pellets during a nuclear power disaster. 3. The six to eight inch thick steel reactor vessel itself is supposed to be the third radiation containment system that creates a barrier against disaster-driven radiation releases, along with its associated pipes that are also made of steel. 4. The emergency core cooling systems were designed to serve as the 4th safety barrier by pumping c water into the reactor to cool the nuclear core 5. Barrier number 5 is the thick wall of steel and concrete called the nuclear containment that was supposed to prevent all the radiation from escaping if the other radiation protection barriers failed. It was the final barrier. The containment itself is passive; it just surrounds all the radioactive material. 6. Finally, in case everything does fail, people living or working within a 10-mile radius of a nuclear power plant are supposed to be able to depend upon its emergency plan and evacuation procedures. All 6 barriers were in place and functioning at the Fukushima Daiichi site when the tsunami hit causing two major problems that engineers never expected: First, when the tsunami destroyed the emergency cooling system back-up diesel generators, the cooling pumps had no electricity to operate and cool the nuclear fuel. Second, the tsunami destroyed the pumps along the ocean that were designed to push cool ocean water to cool the nuclear fuel. Instead of these 6 barriers functioning like the engineers had planned, they fell like dominoes, each failure causing another as the links of the chain were broken. Here is what really happened: The tsunami destroyed the 4th barrier of the emergency core cooling system causing the fuel to overheat and destroy the 1st barrier. The high temperature of the uncooled fuel caused the 2nd barrier of the zirconium alloy cladding to overheat and catch fire. When the fuel cladding caught fire, then the fuel melted through the nuclear reactor destroying the 3rd barrier too. Now only the containment barrier, our 5th and final domino, remains, right? Unfortunately, no. I first spoke to the NRC’s Advisory Committee on Reactor Safeguards in 2010 to share my evidence-based calculations showing that containments would likely leak significant amounts of radioactivity during a nuclear power failure. In response, the ACRS informed me that, the nuclear industry and NRC simply assume that containments will never leak during nuclear emergencies. Inside Fukushima Daiichi’s containment, the pressure increased to more than 100 pounds per square inch causing detonation shock waves and containment failure. Unfortunately, those 3 explosions at Fukushima Daiichi prove that containment systems fail and thousands of people are injured by exposure to significant amounts of radiation. How do we know the containments failed? 1. First, you can see the violent explosions and the detonation shock wave on TV and video. 2. The second picture shows that there are two distinct steam plumes exiting Unit One plume emanates from the spent fuel pool, and the other is directly over the reactor vessel where the top of the containment was supposed to shield everyone and everything from these huge radiation releases. 3. Third, TEPCO itself has admitted that hot gases raging at 250ºF were released from the containment structure. This picture definitely shows the release of hot radioactive gas. And, no, it is not steam, because steam only exists at 212ºF under normal atmospheric pressure. As soon as radiation was released from the plant, the evacuation plans were useless because the plumes were moving wherever the wind and changing weather patterns took them. Not wanting to frighten people, Japanese government employees were not allowed to notify people in time for them to evacuate safely. All 6 barriers failed at Fukushima Daiichi. The failed core cooling caused the fuel to overheat causing the zirconium alloy cladding to catch fire, and that in turn caused the reactor to breach and then the containment system failed. There was no place to run. The Japanese government wants to restart more than half of its 50 remaining nuclear reactors. Back in the 1960s, the NRC made the decision not to require stronger containments and Japan followed America’s lead. You find the 700-page report about the NRC decision to weaken nuclear containments on our website. The triple meltdown at Fukushima Daiichi has proven nuclear safety is a myth, yet the nuclear industry continues to put profits before people with the Japanese government attempting to restart its old reactors with the same 50-year-old containment systems. The NRC has neglected regulations to force major modifications on the 23 containments identical to those that were destroyed by the catastrophe at Fukushima Daiichi. Worldwide, only Germany has taken these disasters and subsequent loss of lives seriously. The Germans have moved ahead with energy efficiency and alternative energy production as methods of protecting their citizens’ lives against the risks inherent in nuclear power production. For me, the lyrics from Peter, Paul, and Mary’s Where Have All The Flowers Gone come to mind, and I wonder when will WE ever learn?








































History of the Evolution of Light Water Reactor Safety in the United States by David Okrent