Nuclear Waste Disposal

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Nuclear Waste Disposal.
The management of nuclear waste disposal is frightening for many people. People are concerned because of the scale of problems that would result from human error. Errors that have occurred in the past frighten individuals into thinking that nuclear energy and nuclear products should be avoided. Also, because nuclear power can be harnessed into weapons of mass destruction, this has made nuclear a feared word. Nuclear waste can be dangerous. Radioactive products, nuclear byproducts resulting from use in modern medicine, and products such as uranium, and plutonium are a concern. Responsible management of these products is crucial to environmental safety and the safety of residents. As many nuclear power plants are coming to the end of their lifecycle, citizens are concerned with how they will be managed. Nuclear waste is stored and the concern of a leak or accident is very troubling. The fact is that organizations responsible for the management of nuclear waste disposal are accountable and run under very detailed and careful processes and regulations with inspections and detailed safety measures. Nuclear energy is clean and safe. Stories about situations like Chernobyl in the Soviet Union frighten people. In that situation, the lid from a Nuclear reactor blew and the resulting fire and radioactive contamination that spread resulted in many deaths. To this day, 3,000 square miles around that power plant remain quarantined due to the contamination. Accidents do happen but overall the management of nuclear waste is handled responsibly. Unfortunately, what happened at Chernobyl taught lessons to power authorities on how handle such situations and has helped to prevent such things from occurring on a larger scale. Nuclear Energy has reduced the world’s dependency on coal and oil. Using coal to create electricity results in many more environmental concerns. The byproducts of coal are excessively worse to the environment than the byproducts of nuclear energy and nuclear waste is more easily contained and disposed of than that of coal. Nuclear waste’s toxicity has a shelf life and an expiration date. Coal power byproducts do not. In managing nuclear waste, some products are buried in sealed containers for either long term or short-term storage. Other products go through a process of transmutation. Transmutation takes the nuclear waste and transforms it into a less harmful product or to a product with a shorter shelf life. All in all, most countries through careful processes are very responsible about nuclear waste disposal.

Wastes from the nuclear fuel cycle Radioactive wastes occur at all stages of the nuclear fuel cycle - the process of producing electricity from nuclear materials. The fuel cycle comprises the mining and milling of the uranium ore, its processing and fabrication into nuclear fuel, its use in the reactor, the treatment of the used fuel taken from the reactor after use and finally, disposal of the wastes. The fuel cycle is often considered as two parts - the "front end" which stretches from mining through to the use of uranium in the reactor - and the "back end" which covers the removal of used fuel from the reactor and its subsequent treatment and disposal. This is where radioactive wastes are a major issue.

Radioactive Waste
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Nuclear Reactors Create Radioactive Waste That Will Remain Hazardous For 240,000 Years More than 50 years after splitting the first atom, science has yet to devise a method for adequately handling long lived radioactive wastes. The Nuclear Regulatory Commission separates wastes into two broad classifications: high-level and low-level waste. High-level radioactive waste is the uranium fuel that fires the nuclear reactor. Once removed from the reactor, the irradiated fuel is considered high-level radioactive waste. Whether in the reactor or in the large pools adjacent, high-level radioactive waste must be cooled by water to prevent it from melting down. Only after spending more than five years cooling in the fuel pool can the radioactive fuel rods be placed in large dry casks at the reactor site. High-level radioactive waste produced by nuclear power plants accounts for 95% of the radioactivity generated in the last 50 years from all sources, including nuclear weapons production. High-level wastes are hazardous because of their high radiation levels that are capable of producing fatal doses within moments of exposure. Once the uranium atoms begin to split, neutrons are given off and absorbed by fuel which produces plutonium and other long lived radioactive wastes. Plutonium 239 has a half-life of approximately 24,000 years. That means that after 24,000 years half of the radioactivity contained in the plutonium will have decayed. However, the hazardous life of radioactive waste is at least ten times the half-life, therefore these wastes will have to be isolated from the environment for 240,000. Because nuclear waste will remain hazardous longer than our ability to contain it, it must be retrievable. Since nuclear waste will remain hazardous for at least 240,000 years it must be monitored in perpetuity. In the short term, nuclear waste should remain at the reactor site or where ever it is currently stored. It is both technologically impossible and scientifically irresponsible to "dispose" of nuclear waste.

Adequately managing these radioactive wastes for 240,000 years is, at best, a daunting proposition. The nuclear industry has already proven itself incapable of keeping track of its high-level nuclear waste for even 30 years. High-level radioactive waste has already gone missing from one, if not several, nuclear reactors. Scientists working on the proposed repository at Yucca Mountain acknowledge that nuclear waste will be hazardous longer than our ability to isolate it from the biosphere. Even attempts to "dispose" of low-level radioactive waste have been an abysmal failure. The only thing "low level" about low-level radioactive waste is its name. Low-level radioactive waste contains the same long-lived and highly hazardous radioactive materials in high-level waste merely in lesser quantities. The NRC basically defines low-level waste as radioactive wastes other than high-level waste. The government has licensed seven sites in the United States to bury low-level radioactive wastes. However, only three of these low-level waste dumps are in operation. They are located in Hanford, Washington; Clive, Utah; and Barnwell, South Carolina. The four closed dumps located in West Valley New York; Maxey Flats, Kentucky; Beatty, Nevada and Sheffield Illinois have all leaked radiation in to the surrounding environment. Concerned citizens have halted attempts to open other low-level waste dumps throughout the country although the nuclear industry's efforts continue, especially in Texas. Since citizen opposition to this irresponsible dumping has driven up costs on the nuclear industry, the Nuclear Regulatory Commission has repeatedly attempted to de-regulate radioactive waste so that it can be dumped into normal land fills and recycled into consumer products.

What makes radioactive waste an international concern? Many other countries in addition to the United States generate electrical power using nuclear fuel. Altogether, there are 436 nuclear power plants around the world, operating in 31 countries. All countries using nuclear power must contend with radioactive waste, regardless of the number of reactors they have in service. Nuclear energy production eventually creates waste in the form of spent nuclear fuel. Spent nuclear fuel is depleted or used fuel from nuclear power plants and research facilities. Spent nuclear fuel is highly radioactive, and remains so for thousands of years. Isolating this high-level waste from people and the environment is an important and challenging issue for countries that use nuclear power. Social, economic, political, technical, and geographic considerations shape a country’s radioactive waste management decisions.

Australia's waste production
While Australia has no nuclear power producing electricity, it does have well-developed usage of radioisotopes in medicine, research and industry. Many of these isotopes are produced in the research reactor at Lucas Heights, near Sydney, then used at hospitals, industrial sites and laboratories around the country. Each year Australia produces about 45 cubic metres of radioactive wastes arising from these uses and from the manufacture of the isotopes - about 40 cubic metres of low-level wastes (LLW), and 5 cubic metres of intermediate-level wastes (ILW). At present Australia has about 3700 cubic metres of low-level waste awaiting proper disposal, though annual arisings are small (the 40 cubic metres would be three truckloads). Over half of the present material is lightly-contaminated soil from CSIRO mineral processing research over 30 years ago.

Basic types of radioactive waste Generally speaking, radioactive waste can be either long-lived or short-lived. Long-lived radioactive waste decays at a much slower rate than short-lived waste, and therefore retains its radioactivity longer. The opposite is true for short-lived wastes. Radioactive waste can also be categorized as low-level or high-level, according to the amount of radiation given off. Low-level radioactive waste Approximately 90 percent of the radioactive waste produced in the world is low-level, yet contains only about five percent of all the radioactivity in low- and high-level waste combined. It can be either short- or long-lived, but most is short-lived. This type of waste consists of lightly contaminated trash and debris, such as paper, clothing, cleaning materials, metal and glass equipment, and tools used in commercial and medical nuclear industries. It also results when nuclear power plants are shut down. Any radioactive waste that is not spent nuclear fuel, high-level radioactive waste, uranium mining residues, or transuranic waste falls into the low-level waste category. Many countries bury their low-level, short-lived waste in protected shallow trenches or concrete-lined bunkers, but some countries choose other options. In the United States, low-level radioactive waste is sent to disposal sites licensed by the Nuclear Regulatory Commission (NRC). Each state, or group of states, is responsible for disposing of and managing low-level waste. Low-level radioactive waste from United States Department of Energy (DOE) facilities is buried on the Nevada Test Site.

High-level radioactive waste High-level waste makes up the smallest volume of radioactive waste, around three percent of the world’s total, but it contains approximately 95 percent of all the radioactivity in low- and high-level waste combined. In the United States, high-level radioactive waste primarily comes from defense-related reprocessing of spent nuclear fuel. All countries with high-level radioactive waste and spent nuclear fuel plan to eventually dispose of these materials deep underground, in a geologic disposal facility called a repository.

International consensus on high-level radioactive waste: deep geologic disposal Underground disposal has been determined by the international scientific community as the best option for permanently separating high-level radioactive waste from people and the accessible environment. Scientists and researchers around the world agree that deep

geologic disposal is technically feasible, provides a waste disposal solution that keeps the public safe, provides for security from intrusion, prevents the diversion of nuclear materials for harmful purposes, and protects the environment for both the short and long term. In addition to the United States, Belgium, Canada, China, Finland, France, Germany, Japan, Russia, Spain, Sweden, Switzerland, and the United Kingdom have invested significant resources in their radioactive waste management programs because of their historic or anticipated reliance on nuclear energy. Despite some differences in their programs, they all support deep geologic disposal as the best method for isolating highly radioactive, long-lived waste. Of these countries, Belgium, Canada, Finland, France, Germany, Sweden, Switzerland, the United Kingdom, and the United States have all performed detailed studies, or characterizations, drilling numerous boreholes and exploratory shafts and ramps in underground research laboratories. The data are useful in determining the predicted safety performance of future nuclear waste repository sites. Common elements of potential repository systems include the radioactive waste, the containers enclosing the waste, the tunnels housing the containers, and the geologic makeup, or type of rock, of the surrounding area. Some countries are individualizing their repository systems, and many are working in collaboration with other countries to develop shared technologies.

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