NUCLEAR FRIEND OR NUCLEAR FOE
On Monday August 6, 1945 the U.S. Bomber Enola Gay flew over the Japanese city of Hiroshima. Seconds later a metallic projectile fell towards its target. In a blinding flash the world felt the power of a new age, the nuclear age.
The study of radiation that would eventually lead to these uranium weapons began in 1798. It was in this year that the german chemist Martin Heinrich Klaproth identified the element uranium. Uranium was not isolated in a metallic state until 1841. The radioactive properties of uranium were first discovered in 1896 when a French physicist Antoine Henti Becquerel studied the properties of uranyl sulfate.
Although science found uranium in 1789, the study of uranium dates back much further. As early as the sixteenth century it was recognized that men who worked in pitchblende( a chemical containing iron ore) mines were subject to fatal pulmonary diseases. An early study of the Schneeberg mines of Germany conducted between 1869 and 1877 found that 650 miners working in the mines had a life expectancy of 20 years after entering the mines.
It was two german doctors, Harting and Hesse, who brought this to the public. The doctors found that 75 percent of the miner deaths were due to lung cancer. But with their scientific knowledge the doctors could only assume that the deaths were caused by the inhalation of arsenic. Later studies between 1900 and 1940 found that the deaths were caused by radiation in the mines.
The radiation the miners were exposed to would later be identified as uranium. Uranium is a natural occurring element, it has a atomic count of 92. Uranium is easily identified by its properties. Uranium melts at about 1132C, boils at about 3818C, and has a specific gravity of 19.05 at 25C. Uranium has three crystalline forms, of which the one that forms at about 770C is malleable and ductile. Uranium is soluble in hydrochloric acids and nitric acids, but not in alkalies.
Uranium never occurs naturally in the free state but is found as an oxide or complex salt in minerals such as pitchblende and carnotite. It has an average concentration in the earths crust of about 2 parts per million, and ranks 48th among the natural occurring elements on earth. Pure uranium consists of more than 99 percent of the isotope uranium-238, less than 1 percent of the isotope uranium-235, and a trace of uranium 234. Artificially produced isotopes of uranium-235, 237, and 239 have also been produced.
Since uranium is rare, a long and difficult process must be used to mine and process the uranium. First the uranium must be mined in a underground or surface uranium ore mine. Next the uranium must be milled. During this process chemicals are used to convert and purify the uranium ore into semirefined oxide( U3O8) known as yellow cake. The second stage in this conversion process is to change the U3O8 into UF6. The next step for the uranium is enrichment. In enrichment, the UF6( which is a gas at room temperature) is forced through about 1700 barriers in which the uranium concentration is increased from the natural 0.7 percent to a level of 3 to 4 percent. The final stage in the preparation of uranium is fuel fabrication. In this process UF6 is converted to uranium dioxide( UO2).
In 1938, the potential of refined uranium was found when Otto Hahn and Fritz Strassman bombarded a uranium metal with a stream of neutrons. At the conclusion of their experiment, they found a trace of barium in the uranium. Later they found that the release of energy and the presence of barium were caused by the splitting of uranium atoms. It was at that moment that the world was first introduced to man controlled nuclear power.
After the successful splitting of an atom, many nations set to work to find a way to produce and extract energy from the reaction. The first generation of electric power from nuclear power was achieved at a reactor testing center in Arco, Idaho. This early generating plant utilized a form of nuclear energy call fission. In this process uranium-235s nuclei is split open when struck by an sub-atomic particle called a neutron. This breaking open releases two or three neutrons which then split open still another uranium-235 nuclei. This reaction releases vast amounts of energy.
This early study of uraniums possibilities also lead to negative programs such as weapons. The most famous of these programs was a secret program launched by the U.S. Government in 1942. The project was code named the Manhattan Project, and was headed by Robert Oppenhiemer. This project was created for the sole mission of creating a nuclear weapon using radioactive materials. The scientist involved in the project decided to use uranium and plutonium for the ammo of the nuclear weapon. The first atomic weapon was detonated on July 16, 1945 at Alamogordo, New Mexico. The bombs designed during the project would later be used on Hiroshima and Nagasaki Japan, thus ending World War II.
Uranium was used in weapons for many years after World War II. After World War II the U.S., Great Britain, France, the Soviet Union, and China conducted many more nuclear weapons test and experiments. These countries also used uranium for many other military purposes. Such examples of this are the launch of the first nuclear powered submarine, the Nautilus, in 1956 by the U.S. Navy and the launch of the worlds first nuclear powered surface vehicle, the icebreaker Lenin, by the Soviet Union in 1957. This use of nuclear weapons continued until president Eisenhower placed a moratorium on U.S. Nuclear weapons test in 1958. Many other countries also decided to stop their nuclear tests during the Geneva conferences in 1955, 1958, and 1964.
Nuclear power was also seen as a gift after World War II. It was after World War II that many nations saw uranium power as having a peaceful purpose. The U.S. was the first nation to start programs for uranium powered nuclear plants. The U.S.s enthusiasm in this area was fully shown when president Dwight Eisenhower delivered his Atoms for Peace speech before the United Nations in 1953. In this speech, the president expressed his opinion that one day almost all of the power in the world would be created by nuclear power.
The first step in this dream was achieved in 1957 when the worlds first power generating nuclear plant began operation at Shippingport, Pennsylvania. This power plant used uranium to perform fission. The heat from the fission heated water, the steam from the water then turned turbines, thus creating electricity. The opening of this plant was a great success, with this success France, the Soviet Union, and the United States made plans to build many more reactors within their borders.
At this time all the information about nuclear power was not known by the public. People knew that uranium was a dangerous but they did not know the extent of its dangers. Due to little information available and clever propaganda, people at this time knew only of the advantages of nuclear power:
1. It is a less expensive energy source than fossil fuels. Electricity produced from uranium is more than 6 times cheaper than electricity produced by coal or oil.
2. Nuclear energy is far cleaner source than the fossil fuels. Though its radiation is dangerous if not contained, it does not dirty the air with pollutants.
3. Nuclear energy works far more efficiently than the fossil fuels because of its ability to generate massive power from small amounts os uranium. One gram of uranium creates as much power as 3 ton of coal Because so little of uranium is needed, the supply will last longer than the fossil fuels.
The majority of the public was for or did not care about uranium nuclear power at this time, but two incidents would bring the full dangers of uranium to the public with a shock.
The first of these incidents happened in 1979 at the nuclear power plant at Three Mile Island near Harrisburg, Pennsylvania. This accident was caused by many things that happened during the time of the accident and before the accident. The first error was a maintenance error and a defective valve which led to a loss of coolant. The reactor itself was shut down by its safety system when the accident began, and the emergency core cooling system began operating as required a short time into the accident. Then, as a result of human error, the emergency cooling system was shut off, causing severe core damage and the release of fission products from the reactor vessel. Although only a small amount of radioactive gas escaped, the financial damage to the utility was very large, $1 billion or more. An official investigation after the accident blamed operational error and inadequate control room design. This accident lead to far more strict building codes of nuclear reactors.
The second of these incidents was perhaps the most famous and easily the worlds worst reactor accident, it happened in a small town called Chernobyl in the former Soviet Union. On April 26, 1986, one of the four nuclear reactors at the plant went out of control. This malfunction was caused by a string of events. An improperly supervised experiment conducted with the water cooling system turned off led to the uncontrolled reaction, which in turn caused a steam explosion. The reactors protective covering was blown off, and approximately 100 million curies or radionuclides( a form of radiation from uranium) was released into the air. Some of the radiation spread across the Soviet Union and into europe. The Soviet Union stated that 31 persons died as a result of the accident, but there is believed to be many more deaths caused by the radiation. More than 100,000 soviet citizens had to be evacuated from the area surrounding Chernobyl. The other three reactors at Chernobyl were returned to operation a year and a half later. It was later seen that the accident could have been reduced if the reactor had a containment building.
It was these two incidents that finally drove the public to seek the truth about uranium. What must be first clarified about uranium is that it does give off radiation, but not all radiation is bad. The average person is exposed to 160.81 milirems of radiation per year. This amount is not dangerous because it is spread out over a amount of time, people are harmed by radiation when they are exposed to large amounts of it at one time.
Uraniums radiation is the first of its many problems. If a person is exposed to natural uranium it can cause many health defects such as radiation sickness and cancer. When people are exposed to large amounts or a reaction of uranium at one time, many more severe health problems can occur such as, burning and death. The threat of radiation seepinf
danger. The radiation present in the soil and water makes the material unfit for animal and human use, and the radiation may linger for many years.
Another problem of uranium is the possibility of it being used for weapons. In todays modern world any one who has access to uranium could build a atomic bomb. Although there is strict regulations on the transport and guarding of uranium, it is still possible that a small amount might just go missing.
Perhaps the greatest uranium problem that we humans face in our nuclear age is the waste created by nuclear plants and weapons. As uranium deteriorate it becomes less valuable and eventually it must be gotten rid of, this is the problem we face. Over the years scientist have thought of many ways to deal with the waste, the most numerous ideas are:
1. Fuel reprocessing: In this process the spent fuel rod are reenriched and used again. The problems with this is that reprocessed fuel rods are not as efficient and a by product of this process is plutonium which can be used in weapons.
2. Land disposal: In this theory spent uranium is inserted into metal canisters and lowered deep in to the ground. This is the most efficient method of disposal to date and is currently being adopted by the U.S. Government. There are numerous problems found with this method. The first is that a site must be found that has little soil movement and no volcanic movement. The second problem is accumulation of uranium and the possible leakage of uranium in to the soil and groundwater. The last problem is that social and political conditions might not guarantee safety and security for the under ground uranium.
3. Incineration: A large percentage of low-level uranium is already incinerated. This process reduces the bulk of the waste by nearly 50 percent. This process also has a few problems that must be addressed. The first problem is that not all nuclear waste can be incinerated. Another problem is the incinerated ashes must still be stored because they still contain radiation. The last and probably greatest problem of this method is the control of the radioactive gases created by incineration.
4. Sub-Seabed disposal: In this theory, spent uranium is buried under the seabed. An advantage of this over land disposal is that seabeds far from the coast are much more stable than land. This method also has a higher rate of security since the waste would be buried beyond the reach of many people. The problems associated with this are; location, method of putting waste into seabed, and a way to safeguard the materials from accidents.
5. Nuclear depositories: This theory states that nuclear wastes should be stored inside of highly secured storage facilities. This theory makes logical sense but is unpopular with the public. People are not willing to pay higher taxes for these facilities and people are not comfortable with one of these facilities being near them. The U.S. Government has already started construction of one of these facilities in the Yucca mountains of Nevada.
All of these methods are viable methods but we must meet there problems before we can use them.
Due to the over whelming facts against nuclear power, the U.S. Has practically halted production of nuclear reactors but continues to run these reactors, but as we slow down our nuclear program many other countries are increasing theirs at a astonishing rate. By 1989, 112 nuclear plants were present in the U.S., in addition there were 316 plants in 40 countries outside the U.S.. The U.S. still has uranium ore mines in Colorado, Utah, New Mexico, Arizona, and Wyoming, with foreign mines found in Canada, the Democratic republic of the Congo, and parts of Eurasia. The United States and the former Soviet Union have also had peaceful negotiations to reduce the number of uranium weapons in their arsenals. But even though the U.S. has made drastic cutbacks in the amount of uranium used, we still use quite a bit, to be more precise the U.S. used 3417 metric tons of the 29,100 metric tons of uranium produced world wide.
As mankind approaches the new millennium we are faced with many problems, but maybe no problem is as big as the pandoras box we call the nuclear age. At the center of all the nuclear activity is the simple element, uranium, who has been present since the beginning of time. We as humans must decide the fate of not only the nuclear program but the fate of our specie. If we are to leave this simple element and the problems it has brought unchecked, the doom of our society due to weapons or our simple radiation pollution, could be a reality we are not yet ready to face. On the other hand, if we work together to find the full potential of uranium, we could achieve things that we could not even dream of. The choice me make must be the right decision because with that strong decision, we not only affect us, we do not only affect our specie, we may effect the fate of our world for the never ending expansion we call eternity.
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