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An Environmental Movement Emerges - Silent Spring
Silent Spring is a book written by Rachel Carson and 1st published in 1962. The book is widely credited with helping launch the modern day American environmental movement.
Carson was already a well-known writer on natural history at the time of the book's publishing,, but had not previously been a social critic. The book quickly became widely read and made the New York Times best-seller list. It inspired widespread public concerns with pesticides and pollution of the environment. Most people believe that the impact of the book led to the creation of the Environmental Protection Agency (EPA) in 1970 and the eventual ban of the pesticide DDT in 1972.
The book documented detrimental effects of pesticides on the environment, particularly on birds... claiming that there continued use would eventually lead to a "Silent Spring" as birds would die off and not fill the air with chirping. Carson accused the chemical industry of intentionally attempting to mislead the public and government officials about the effects of their products on the environment and potentially on all living things.
Silent Spring has been featured in many lists of the best nonfiction books of the twentieth century. In the Modern Library List of Best 20th-Century Nonfiction it was at #5. Silent Spring was also named one of the 25 greatest science books of all time by the editors of Discover Magazine.
Carson was already a well-known writer on natural history at the time of the book's publishing,, but had not previously been a social critic. The book quickly became widely read and made the New York Times best-seller list. It inspired widespread public concerns with pesticides and pollution of the environment. Most people believe that the impact of the book led to the creation of the Environmental Protection Agency (EPA) in 1970 and the eventual ban of the pesticide DDT in 1972.
The book documented detrimental effects of pesticides on the environment, particularly on birds... claiming that there continued use would eventually lead to a "Silent Spring" as birds would die off and not fill the air with chirping. Carson accused the chemical industry of intentionally attempting to mislead the public and government officials about the effects of their products on the environment and potentially on all living things.
Silent Spring has been featured in many lists of the best nonfiction books of the twentieth century. In the Modern Library List of Best 20th-Century Nonfiction it was at #5. Silent Spring was also named one of the 25 greatest science books of all time by the editors of Discover Magazine.
This is a picture of Rachel Carson at around the time Silent Spring was published. She fought cancer for the last 15 years of her life before passing away in 1964 at the age of 57. During that time, her book and testimony in front of the U.S. Congress led to serious investigations on the effects that certain pesticides had on the environment and directly led to the banning of 1 of them (DDT) in 1972.
The Rise and Fall of DDT in the U.S.
This short 3 minute clip highlights the origins of DDT and the push to eventually get it outlawed in 1972.
The Nuclear Energy Debate
Nuclear power in the United States is provided by around 100 reactors licensed to operate at 65 nuclear power plants around the country (you will see most reactors paired together on the map above), In all, they produce roughly 20% of the total electric energy generation in 2008. The United States is the world's largest supplier of nuclear power.
All US nuclear power plants, and almost all reactors,began to be built in 1974 or earlier. After the Three Mile Island accident in 1979 (a separate article on the bottom of this page), many planned projects were canceled. Of the reactors now operating in the U.S., ground was broken on all of them in 1974 or earlier. There has been no new ground-breaking on nuclear plants in the United States since 1974, though a number of reactor units started before 1974 have been completed since then.
Construction had begun on new units at existing plants in 2011, but the 2011 Japanese nuclear accidents caused by a tsunami has caused delays. Leading U.S. officials anticipate that five new reactors to enter service by 2020, all in the Southern U.S. and all at existing plants.
All US nuclear power plants, and almost all reactors,began to be built in 1974 or earlier. After the Three Mile Island accident in 1979 (a separate article on the bottom of this page), many planned projects were canceled. Of the reactors now operating in the U.S., ground was broken on all of them in 1974 or earlier. There has been no new ground-breaking on nuclear plants in the United States since 1974, though a number of reactor units started before 1974 have been completed since then.
Construction had begun on new units at existing plants in 2011, but the 2011 Japanese nuclear accidents caused by a tsunami has caused delays. Leading U.S. officials anticipate that five new reactors to enter service by 2020, all in the Southern U.S. and all at existing plants.
How it works
Nuclear power is generated inside a plant called a reactor. The power source is the heat produced by a controlled nuclear fission chain reaction, either of uranium or plutonium. This reaction involves an element, such as uranium or plutonium, being struck by a neutron and splitting. The result of the fission of these large atoms are the creation of new, smaller atoms as byproducts, radiation and more neutrons. Those neutrons speed out and strike other uranium/plutonium atoms, creating a chain reaction. The chain reaction is controlled by neutron moderators, which vary depending on the design of the reactor. This can be anything from graphite rods to simple water. Once the heat has been released, a nuclear reactor produces electricity in exactly the same manner as any other thermal-based power plant. The heat converts water into steam, and the steam is used to turn the blades of a turbine, which runs the generator
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Pros and Cons of Nuclear Power
Pro
Energy Independence
No Air Pollution
Energy Independence
No Air Pollution
- Nuclear energy does not involve burning fossil fuels, and therefore does not in any way contribute to greenhouse gas emissions. In this respect, it is as clean as solar, wind, and water power... as long as nothing goes wrong....
Con
Nuclear Safety
Nuclear Safety
- A nuclear accident that resulted in loss of control over the fission chain reaction would be extremely hazardous. The danger is that the heat produced would outstrip the ability of the reactor coolant to cope, potentially allowing the nuclear reaction to run wild. This could cause system failures which would release radioactivity into the environment. In the case of an extreme failure, the result would be a nuclear meltdown, where the reacting nuclear material burns or melts its way through its containment vessel into the ground and then into the water table. This would throw a huge cloud of radioactive steam and debris into the atmosphere. Accidents of this type have the potential to release radioactivity over an immense area. A small, well-contained accident might just contaminate the power plant, while a major one could result in fallout being spread worldwide. While nuclear power has become safer with the introduction of new reactor designs and technologies, it still carries with it a risk that no other source of power does.
- According to the U.S. Department of Energy, when all costs are factored in, nuclear power costs an estimated $59.30 per megawatt hour. This is expensive when compared to other means of generating electricity. For example, clean wind power is $55.60/MWH; coal $53.10/MWH; and natural gas $52.50/MWH.
- Spent fuels from a nuclear power plant are radioactive and highly toxic.They also pose security risks, as a terrorist who acquired a substantial amount of nuclear waste could construct a so-called "dirty bomb," with the purpose of spreading radioactive materials over a large area. An accident or attack involving radioactive waste would likely contaminate a strictly local area.
Three Mile Island and Chernobyl
This 45 minute Modern Marvels special from the History Channel focuses on 2 of the most famous nuclear disasters ever. The first 35 minutes discusses the 3 Mile Island incident. The last 10 minutes focuses mainly on Chernobyl and how only half of 3 Mile Island still functions today. It's really good, but probably too long to show in class
Three Mile Island
2 minutes long. Good summary of history of nuclear power in U.S. and the impact that this incident had on any new plants in U.S.
Chernobyl
Brief 3 minute summary of what happened, how many people were affected, and what it's like today..