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==A Brief Description of the Power Plants== |
==A Brief Description of the Power Plants== |
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The Fukushima nuclear power plants are two separate nuclear power plants located along the eastern coast of Honshu. These are the [[Fukushima Daiichi Nuclear Power Plant|Fukushima Daiichi]] power plant (Fukushima I), with six reactors, and the [[Fukushima Daini Nuclear Power Plant|Fukushima Daini]] power plant (Fukushima II), with four reactors. |
The Fukushima nuclear power plants are two separate nuclear power plants located along the eastern coast of Honshu. These are the [[Fukushima Daiichi Nuclear Power Plant|Fukushima Daiichi]] power plant (Fukushima I), with six reactors, and the [[Fukushima Daini Nuclear Power Plant|Fukushima Daini]] power plant (Fukushima II), with four reactors. |
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Revision as of 09:19, 2 December 2011
The Earthquake
On Friday, March 11, 2011, a powerful magnitude 9.0 earthquake struck Japan; it was centered off the east coast of Japan's Honshu Island. This earthquake, and its resulting tsunami would go on to wreak havoc on Japan's nuclear power industry.
Why Does Japan Use Nuclear Power?
Japan is located along the Pacific Ring of Fire, a region of frequent and intense earthquake activity. Despite this, Japan had little choice but to construct nuclear power plants, as it has little coal or oil available for use. There are some rivers in the country that are dammed, but these hydroelectric dams produce only about 7% of the electricity Japan needs1.
A Brief Description of the Power Plants
The Fukushima nuclear power plants are two separate nuclear power plants located along the eastern coast of Honshu. These are the Fukushima Daiichi power plant (Fukushima I), with six reactors, and the Fukushima Daini power plant (Fukushima II), with four reactors.
Construction
Being in such an earthquake-prone area ensures there was a lot of data recorded about seismic activity in Japan. When the plants were originally designed, engineers noted that the most powerful earthquakes in the area were typically of magnitude 7 to 82. 40 years ago, when the plants were built, knowledge of seismology was less than that of today. However, through the years, with advances made in the knowledge of earthquakes, a corresponding update in the ability of the plants to withstand earthquakes and tsunamis failed to occur2. In fact, the inital landscaping of the current power plant site actually increased risk of damage by tsunami. Originally, where Fukushima I now stands was a 35 metre high seaside cliff. However, TEPCO, the power company responsible for overseeing the plants reduced the height of that cliff to 10 metres, based on their assumption of a maximum tsunami height of 3 metres3. Although offshore breakwaters were also installed, these would provide protection against only typhoons, not tsunamis. This lack of consideration for tsunamis was noted in government regulations, too. It was not until 2006 that tsunamis were explicitly mentioned in the Japanese government’s standards for nuclear power plants4.
Potential Concerns
The Fukushima reactors were owned and operated directly by the electric company TEPCO. Despite assurances from TEPCO that their reactors were completely safe and earthquake resistant, some scientists remained skeptical5. Aside from the views of concerned scientists, the political and business side presented a serious obstacle to the prevention of this disaster. The Japanese government has been seen as too weak in its dealings with the power companies, and there exists no centralized framework in the government for crisis management5. This is compounded by the fact that there is no person who is the one central decision maker. Instead, people such the Prime Minister, and the directors of the power companies are all likely to be involved in the decision process in crises. A situation like this leads to exactly what happened at Fukushima: the companies responsible for running the power plants refuse to see a problem until it is too late, and the fragmented leadership and lack of effective decisions leads to a response that is too slow and ineffective.
Environmental Impacts
As one might expect from a serious nuclear accident, there were a few environmental impacts associated with this disaster. The first such impact was the release of radioactive materials; these were mostly released into the atmosphere and seawater. Radioactive material was released into the atmosphere primarily through the release of radioactive steam, explosions, and fires in spent fuel ponds. Seawater was exposed to radiation mostly by radiated groundwater, and the discharge of radioactive water from the reactors. When measured on April 6, it was found the ocean near the disaster site had a radiation level of 68 million Bq/m3 (cesium-137)9. Consider the impact that such a vast amount of radiation can have on marine life; there are a wide variety of organisms such as fish and plankton that could potentially intake this radiation. However, this uptake of radiation by fish also has an impact on humans. What happens to radioactive fish when they enter the human food supply? Fortunately, however, since the activities of radioactive material have been quickly decreasing since the incident, theoretical dose calculations would suggest that the seafood supply is not in immediate danger9. However, considering the short amount of time that had passed, the full effects of this incident on the ocean are probably not quite known yet. One of the components released into the atmosphere was cesium-137 (137Cs). This is a radioactive metal, with a half-life of about 30 years. Cesium is located within the first group of the periodic table, in the same column as potassium and sodium. As such, the human body considers it to be chemically similar to those elements, which could result in the absorption of radioactive materials into the human body. It is known that 137Cs was released into the atmosphere from this incident, however, estimates very as to how much cesium was actually released. Depending on the source, estimates can vary from 7.7 x 1017 Bq to 2.4 x 1018 Bq (5 to 17% the amount that was released in the Chernobyl disaster)10. As with Chernobyl, permanent evacuation of the area is the only solution if the land is deemed to be too radioactive. In Ukraine after the Chernobyl disaster, people living on land recorded to have radiation levels greater than 0.5 MBq/m2 were forcibly resettled. In the aftermath of the Fukushima disaster, a radiation level of 3.7 MBq/m2 was noted on some lands near the power plants11. So, the long-term solution appears to be similar to the one imposed after Chernobyl: permanent evacuation and resettlement from lands that are deemed inhabitable.
Impacts on Nuclear Power in Other Regions
After the Fukushima incident, questions about nuclear power in other countries were raised. For example, immediately after the Fukushima accident, the German government announced that it would immediately shut down its oldest nuclear reactors. This would be followed by the gradual decommissioning of all remaining nuclear power plants in Germany over the next 10 years. Considering that nuclear power was responsible for 29% of Germany’s electricity production12, this will leave a huge gap to be filled for Germany’s future power needs. This is an exceptionally strong reaction, considering the differences between the geography of Germany and Japan. Japan, which is located at the intersection of the North American, Eurasian, and Philippine plates, is very prone to earthquake activity due to the presence of those fault lines. On the other hand, Germany is located far away from any major fault lines, and is thus far less earthquake-prone than Japan. Thus, although fears of nuclear power in Germany were awoken after the Fukushima incident, the difference in geographies of the two countries presents two very different scenarios. Instead, it was noted that without nuclear power, Germany’s economy could suffer, due to switching from an electricity exporter to an electricity importer12. Another country potentially impacted by this disaster is Taiwan. Taiwan, like Japan, is located along the Pacific Ring of Fire, and also suffers from frequent earthquakes. Taiwan has three active power plants, and one under construction, all of which, like Fukushima, are located along the coastline. Much like the Japanese government prior to the Fukushima incident, the Taiwanese government tried to deny that such a disaster could ever take place in Taiwan. However, a report made by the World Nuclear Association revealed that it had named all of four of Taiwan’s nuclear power plants among the top 14 most dangerous plants in the world13. After Fukushima, there were many protests demanding that the government shut down the power plants in order to prevent a similar disaster in Taiwan. However, in the end, unlike Germany, Taiwan did not shut down any reactors, and construction of the fourth power plant remains ongoing. This is a risky move, as the world has seen what can happen when nuclear power plants are not built strong enough to withstand powerful earthquakes and tsunamis.
References
- Ramseyer, J.M. Theoretical Inquiries in Law. 2012, 13(2) (To be published)
- Onishi, N.; Glanz, J. Japanese Rules for Nuclear Plants Relied on Old Science, The New York Times, March 26, 2011.
- Yoshida, R.; Fukada, F. Fukushima plant site originally was a hill safe from tsunami, The Japan Times, July 12, 2011.