INTERESTING FACTS ABOUT NUCLEAR POWER AND NUCLEAR DISASTERS
A nuclear and radiation disaster is defined by the International Atomic Energy Agency as “an event that has led to significant consequences to people, the environment or the facility.” The International Nuclear and Radiological Event Scale (INES) is a worldwide tool for classifying nuclear and radiological events.
Events are classified on the scale at seven levels: levels 1-3 are “incidents,” and 4-7 are “accidents,” with a “Level 7 Major Accident” consisting of “a major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures.” The scale is designed so that the severity of an event is about ten times greater for each increase in level on the scale.
There have been three major atomic disasters in 35 years. In 1979, at Pennsylvania’s Three Mile Island nuclear power plant, a combination of design and operator errors caused a gradual loss of coolant, leading to a partial meltdown . In the worstcase scenario, a meltdown breaches the containment building resulting in a massive release of radiation. Thankfully, this did not occur at Three Mile Island. However, some radioactive gases did escape into the atmosphere. The estimated average dose to area residents was about one-sixth the exposure from a full set of chest x-rays, and about 1/100th of the natural radioactive background dose for the area. This disaster did expose 2 million residents to low-risk radiation and it took 14 years and $975 million to clean up after the disaster took place. The disaster at Three Mile Island was classified as a level 5 accident according to INES.
The worst nuclear power plant accident in history occurred in the Ukraine in 1986. The disaster began during a systems test at reactor number four of the Chernobyl plant. There was a sudden surge of power output, and when an emergency shutdown was attempted a more extreme spike in power output occurred, which led a reactor vessel to rupture and resulted in a series of explosions. These events exposed the graphite moderator of the reactor to air, causing it to ignite. The resulting fire sent a plume of
highly radioactive smoke into the atmosphere and over an extensive geographical area. This toxic plume went on to drift over large parts of the western Soviet Union and Europe. The explosions at the Chernobyl Power Plant killed 30 workers and caused the relocation of 300,000 residents from the surrounding areas. A permanent 30 km exclusion zone around the reactor was established. The Chernobyl disaster released a hundred times more radiation than the atom bombs dropped on Nagasaki and Hiroshima in WWII. The accident contaminated 160,000 square kilometres of land and, according to the last Soviet leader Mikhail Gorbachev, it was a factor in bringing about the collapse of the Soviet Union in 1991. This disaster received a “Level 7 Major Accident” rating on INES.
Japan has had three nuclear power plant accidents since 1999. The most recent and devastating one took place in 2011 at the Fukushima Nuclear Power Plant. Major damage to the backup power and containment systems caused by the 2011, 9.0-magnitude Tōhoku earthquake and tsunami resulted in overheating and leaking from some of the Fukushima I nuclear plant’s reactors. Each reactor accident was rated separately using INES; out of the six reactors, three were rated level 5, one was rated at a level 3, and the situation as a whole was rated level 7. A temporary exclusion zone of 20 km was established around the plant as well as a 30 km voluntary evacuation zone. The meltdown of three Fukushima reactors forced 160,000 people from their homes, destroying local fishing, farming and tourism industries along the way. Even if no deaths have yet been officially linked to Fukushima radiation, cleanup costs have soared to an estimated US$196 billion and could take more than four decades to complete.
These three high- profile disasters “are the only major accidents to have occurred in over 14,500 cumulative reactor- years of commercial nuclear power operation in 33 countries” according to the World Nuclear Association ( WNA). After Japan’s nuclear disaster in 2011, several countries have reexamined their reliance on nuclear energy. Germany plans to close all of its reactors by 2022 and Italy and Switzerland have halted expanding their nuclear power. While atomic power has fallen out of favour in some European countries, it is proving to be a popular energy source in Asia as an alternative to coal. China is building 28 reactors, while Russia, India, and South Korea collectively have 21 currently under construction, as reported by the WNA. Of the 176 reactors planned, 86 are in countries that had no nuclear plants two decades ago, WNA data shows.
It seems clear then that nuclear power is still one of the best ways to meet the world’s growing demand for electricity without generating substantial amounts of greenhouse gases. No other form of renewable energy is up to the task. What then must take priority is how to contain and manage the possible dangers of nuclear power. Joonhong Ahn, a professor in the department of nuclear engineering of University of California, Berkeley believes the consequences of radiation release, contamination and evacuation are “clear and obvious,” that means governments and citizens should be prepared for a major catastrophe, not just nuclear facilities. According to Professor Ahn, when the next nuclear accident occurs, the world needs to have better knowledge of how to limit the spread of radiation and do the cleanup, including removing radiation from the soil and water and have an efficient evacuation drill for the population in danger zones. Otherwise, another Chernobyl or Fukushima- type disaster beckons.
1. Nuclear power plants use nuclear fission, which is the process of splitting an atom into two. Nuclear fusion works the other way; it is the process of combining atoms into one. Nuclear fusion is considered to be safer than nuclear fission. Unfortunately, nuclear fusion technology has yet to be developed on a substantial scale.
2. In 1905, Einstein discovered that mass can be converted into energy and vice versa. In 1918, Sir Ernest Rutherford demonstrated that atoms can be split. By 1942, the world had created its first nuclear reactor.
3. Nuclear explosions can discharge high levels of radiation that eliminates electrons from atoms and can destroy DNA.
4. The first catastrophic effect from nuclear energy was evident in August 1945, when America dropped two atomic bombs on the Japanese cities of Hiroshima and Nagasaki.
5. The Chernobyl disaster discharged a hundred times more radiation than the atomic bombs dropped on Nagasaki and Hiroshima in World War II. The environmental group, Greenpeace, states that the death toll of the Chernobyl disaster will be almost 100,000.
6. We know that the regions near a nuclear explosion are immediately exposed. However, the radiation can stay in the atmosphere for decades, covering widespread areas before settling on the earth’s surface.
7. The most potent nuclear weapon that ever ignited was Russia’s Tsar Bomba. It is the single most physically powerful device ever produced by man. 8. If you discard your outer clothing that has been exposed to nuclear radiation, you can remove up to 90% of radioactive substances that you would otherwise be exposed to.
9. 2000 nuclear explosions have been detonated in the world between 1954 and 1996, and 25% of them (over 500 bombs) were detonated in the atmosphere. Most of these have been detonated underground. In fact, 75% of all the nuclear tests that were carried out during the Cold War were detonated underground.
10. Worldwide, there are over 430 commercial nuclear power reactors distributed over 31 countries. 11. The world’s first nuclear power plant that was built to generate electricity for a power grid is USSR’S Obninsk Nuclear Power Plant, which launched on 27 June 1954.
12. A nuclear war can kill about 1 billion people and injure hundreds of millions of people. The 3-4 billion people left alive would be affected by widespread radioactive contamination, a potential nuclear winter, amplified levels of damaging ultraviolet rays resulting from partial destruction of the ozone layer, a global photochemical smog, as well as a host of toxic pollutants.
13. The peace symbol that we commonly see around the world was initially an anti-nuclear weapons symbol.