Nuclear energy is a widely used source of power in Japan. As a result of the earthquake and tsunami, damage to the nuclear power plants has resulted in several explosions and the release of radioactive material. While the media is fixated on the threat posed by the imperiled nuclear power plants, there is a significant amount of misinformation, information without context, information in the wrong context, and complex information that is just not explained adequately in the media's coverage.
The following list will hopefully clear up some of the confusing information I've seen in the popular coverage of Japan's nuclear situation.
|Diagram of the type of reactor at Fukushima|
Source: Nuclear Energy Institute
2. Comparisons to Chernobyl or Three Mile Island are difficult to make: Chernobyl, located in the Ukraine, was a nuclear disaster that occurred on April 25, 1986 due to a flawed reactor design and human error. The Chernobyl reactor was of a soviet design, and according to the World Nuclear Association, "the design of the reactor is unique and the accident is thus of little relevance to the rest of the nuclear industry outside of the Eastern bloc." Chernobyl was the only nuclear accident to cause human deaths due to direct exposure to radioactive material. Comparisons can be made to the situation in Japan about the extent of damage, but only once the situation is under control has been thoroughly assessed. Three Mile Island was an American accident in 1979 that occurred when a cooling malfunction caused part of the nuclear reactor's core to melt. There were no adverse health effects associated with any radiation released from the plant after the accident. The build up of hydrogen gas following the meltdown was a factor in the Three Mile Island accident, and is causing problems in Japan but again differences in exact reactor design and protocol make it difficult to compare the situations.
INES scale runs from 1 (very little danger to the general public) to 7 (widespread health and environmental impacts). Right now everyone is rushing to label the situation in Japan, but so far it is classified as somewhere between level 4 and level 6. The numbers (or levels) are not hard and fast, but it is a clear indication that this is a major event and should be treated with all necessary precautions to ensure the safety of the Japanese people.
4. Radiation is not distributed evenly: When a nuclear power plant experiences an explosion or a meltdown that causes the release of radioactive particles or debris into the environment it can be very complicated to track what areas are going to be effected by radiation. According to members of the Union of Concerned Scientists precipitation like wind or rain can cause the radioactive material to be distributed sporadically. The areas closest to the effected plant will be the first concern for scientists and policy makers assessing the radioactive fallout, but other areas (even far from the immediate vicinity of the plant) need to be assessed for radioactivity.
|Map of Japanese Nuclear Sites|
Source: International Nuclear Safety Center
Reuters has a great info graphic, that breaks down the earthquake, tsunami and the nuclear disaster. The BBC also has an interesting article about the way that nuclear situation in Japan will impact further nuclear development around the world. As more information comes out I'll try to update this post, but I hope that I've been able to provide some background on elements that I've seen in multiple articles about Japan's nuclear situation.