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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), and the Fukushima Daini power plant (Fukushima II). Fukushima I, the larger of the two plants, had a total of six reactors, compared to Fukushima II’s four reactors. Why Nuclear Power in Japan? Despite being one of the world’s most earthquake-prone countries, Japan had little choice but to construct nuclear power plants. Japan is not a country rich in coal, oil, or natural gas reserves. There are some rivers in the country that are dammed, but these hydroelectric dams produce only a small fraction of Japan’s energy needs2. Thus, one of the few ways for Japan to meet its electricity requirements is through nuclear power. History of Power Plant Construction The history of earthquakes along the coast of Honshu is quite well recorded; it is known that very large earthquakes will often hit this area, and tsunamis frequently develop from those earthquakes. Since these nuclear plants were built and designed about 40 years ago, engineers responsible for designing the plant would have had less knowledge of seismology as compared to what we know today about earthquakes. Although earthquakes were taken into account, the landscaping of the area prior to construction actually made the plant more vulnerable to tsunamis. The site of construction for Fukushima I was originally a 35 metre high seaside hill. In order to reduce the operating costs of seawater pumps that would provide coolant water for the plant, the hill’s height was shaved down to 10 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. Timeline of Events6, 7,8 (all times in this section given in Japan Standard Time) March 11, 2011

2:46 PM: The earthquake begins.

3:27 PM: The first wave strikes the power plant. 9:00 PM: Evacuation begins for those living within 3 km of the plant. March 12, 2011 5:30 AM: Radioactive steam is released to relieve pressure in the reactors. 3:30 PM: An explosion occurs at Fukushima I. 8:20 PM: Injections of seawater begin in an attempt to cool the reactors of Fukushima March 14, 2011 • Fukushima I cooling systems fail March 23, 2011 • Power restored to three reactors of Fukusima I March 24, 2011 • Two workers die due to radiation exposure March 26, 2011 • Tokyo Electric Power Company (TEPCO) announces the decommissioning of Reactors 1, 2, 3 and 4 of Fukushima I April 12, 2011 • The nuclear crisis is rated at Level 7 on the International Nuclear Event Scale. This is the most serious ranking on the scale, and only the second time in history a nuclear accident has been rated at Level 7 (the first to rate at Level 7 was the Chernobyl disaster). 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.