The earthquake of magnitude of 9.0 (revised on Monday) in the Richter scale hit Japan on Friday. The biggest earthquake which hit the islands for almost 140 years. Japan is used to the quakes, most of them do not cause too much damage to the buildings any more (thanks to the strict anti-quake building code). The last, which was a devastating blow to the country was so called Kobe Earthquake in January 1995, which had a magnitude of 7.3. The city was in ruins and approximately 6,434 people lost their lives (final estimate as of December 22, 2005); about 4,600 of them were from Kobe. The building code has been since improved, the city has been rebuilt in 85%.
The earthquake which came unexpectedly on Friday, March 11, 2011 had an epicenter several miles to the East of the Pacific shore. It was felt in the whole country causing a limited damage even in Tokyo. However, the most devastating was the Tsunami following the tremors. It swapped the Eastern shore of the Japanese Islands leveling everything standing on it's way with the 30 feet high wave. The whole cities on the cost simply disappeared. Thousands of people lost their lives. The official government statement said that it was the most terrible disaster in the post-war Japanese history. A long time will pass before the grim effect of this catastrophe will be known in detail...
All of the developed countries immediately rushed to help the suffering people of Japan. The needs of all the affected people and their fate are on the minds of everyone in the World.
Unfortunately, the Friday earthquake caused the damage to some reactors in the Japanese Nuclear Power Plants.
Japan's electrical power needs are enormous. Since 1973 the nuclear energy has been a national strategic priority. At this point, Japan is the third largest user of nuclear generated power, with 53 working nuclear reactors. They provide about 35% of Japan's electricity. Their nuclear industry has been operating without any major catastrophe (like Three Mile Island accident or the Chernobyl disaster). However, starting in the mid-1990s there were several nuclear related accidents and cover-ups in Japan that eroded public perception of the industry, resulting in protests and resistance to new plants. These accidents included the Tokaimura nuclear accident, the Mihama steam explosion, cover-ups after an accidents at the Monju reactor, among others, more recently the Chūetsu offshore earthquake aftermath (6.6 magnitude in 2007).
It brings us to the aftermath of the latest, huge earthquake followed by a tsunami. Although the most of the power plants haven't reported any damages - the Fukushima Daiichi plant – which runs on a plutonium-based fuel, developed the grave problems. Directly as a result of the quake, the reactor's #3 cooling system failed, causing the overheating of the core. It lead to the exposing of the fuel rods, generating the Hydrogen in the containment area, what lead to the explosion of the Hydrogen rich atmosphere and the destruction of the containment structure. Reports warn about the similar damage to the neighboring reactor. Although the radiation levels so far haven't been catastrophic, and thousands of the people have been evacuated from the immediate proximity of the plant to the safe distance, experts warn of the possibility of unprecedented nuclear disaster. So far a number of the inhabitants of that area have been exposed to some radiation, prior to the evacuation.
What we have to take under consideration is that Japan is located in the most active seismic area in the World - so called "Ring of Fire". Japan lays on the junction of the three major tectonic plates: North American, Eurasian and Pacific plates, and is close to the Phillipine plate. It is well known that the earthquakes are a part of normal life of this country. It is also known, that sometimes the nature goes beyond the "usual" and surprises us with it's ferocity. In such a context it's very arrogant to assume that the man-made structure (and man-made machinery) is constructed robustly enough to withstand a 'surprise attack' by the Mother Nature. Apparently the latest earthquake is more than these structures can handle.
If we use a 'statistical' approach to assess the 'survivability' of the structures like a conventionally powered power plant - we may accept a small percentage of the projected failures. Any damage to these conventional plants may cause death and injury to some people, but the affected area would be limited to local only, and the damages wouldn't leave any lasting contamination.
WE CAN'T APPLY STATISTICAL APPROACH to the assessment of the projected damages to the nuclear plans. We, as a humanity, can't control the nuclear reactions if anything goes wrong. We can't prevent the release of the radioactive gasses, steam, or water if there is any failure of the plant's infrastructure.
So far almost 2 hundred people have been exposed to some levels of radiation. If the repair teams succeed cooling down the 2 problematic reactors, maybe there will be no more harm done to the population. However, the assessment of the situation which transpires from the reports is far from being that optimistic. We heard already about the possibility of the meltdown, or explosion... If it happens, the affected area may be enormous (depending on the prevailing direction of the winds carrying the radioactive cloud).
Is it so difficult understanding, that although generally safe, in the crisis situation, the nuclear power plants are EXTREMELY DANGEROUS. And the danger goes far beyond the Japanese Islands, and it's not limited to the present only, but may be extended for many decades ahead.
The World's resources of the Uranium are already scarce (although it might be argued based on the increase of the technology involved in exploration, recovery, and the use of lower-content ore). The next technological step is application of the Plutonium as a fuel of the reactors, mixed uranium and plutonium oxide, to be precise. This fuel is much more difficult to handle, runs in much higher temperatures and if not cooled properly leads to the MELTDOWN when the temperature rises to 2200 degrees Celsius. If not cooled, the core of the reactor reaches that temperature very soon (at the temp. of 1000 C the water converts to hydrogen and another explosion is likely).
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