Commercial nuclear waste is not green ooze which may have been inspired by liquid-form nuclear weapons waste like that at Hanford. You may also hear nuclear waste referred to as spent nuclear fuel or used nuclear fuel. These terms are intended to indicate that it is recyclable, but they all refer to the stuff known commonly as nuclear waste. When a nucleus splits, most of the energy is released immediately and carried off by coolant to do useful work.
However, energy continues to be released for thousands of years after the atom splits. This afterglow heat is what makes nuclear waste hazardous. Unlike most toxic waste, the fact that nuclear waste becomes less toxic with time is quite unique. These delayed energetic emissions mean that nuclear waste is highly radioactive. When it first comes out of the reactor, it is so hazardous that if you stood close to it while it was unshielded, you would receive a lethal radiation dose within a few seconds and would die of acute radiation sickness [wikipedia] within a few days.
As the energy emerges, the waste becomes less radioactive and so also less hazardous every moment. Still, it does not transform from hazardous to benign for thousands of years. The nuclear waste question fundamentally asks whether or not humanity can prevent this radioactive material from causing harm to people and the environment. It is not clear that the public will accept an energy source that produces this much radioactivity. Since he made that statement, we have gained more than 60 years of experience with nuclear power stations.
So how have we done? In practice, the spent fuel is never unshielded. It is kept underwater water is an excellent shield for 5—8 years in spent fuel pools until the radiation levels decay to levels that can be cooled without water.
After cooling in the spent fuel pools, nuclear waste is either recycled France or moved into large concrete canisters called dry casks most other places. These casks hold several spent fuel assemblies each. The following video shows a world-expert in nuclear waste walking amongst the spent fuel in dry casks at the Columbia Generating Station in Washington state. To our knowledge, no one has been injured or killed by commercial nuclear waste in dry cask storage.
While future incidents are possible, it is fairly clear that the rate of injury from this material pales almost in insignificance compared to the 8 million people per year who actually do die from air pollution complications caused by fossil fuel and biofuel emissions WHO numbers.
The fact that nuclear plants keep all of their waste on site for their entire lifecycle can be considered a major positive environmental attribute compared with energy sources that emit vast waste into the atmosphere or produce vast manufacturing wastes during fabrication. In France, the waste that comes out of the recycling process discussed below is turned into glass in a process called vitrification , and then stored in air-draft cooling racks.
Dry cask storage above ground is quite stable, but both nuclear advocates and opponents can agree that there are reasons to try to get it even further away from the biosphere. There is scientific consensus that putting the nuclear waste in geologic formations that are expected to be stable for many millions of years is appropriate e.
This way, if the material is released in the far future, it will have already released all of its afterglow heat and will be radiologically inert. The US studied and constructed large portions of Yucca Mountain as the national spent fuel disposal site, but the community was not consulted sufficiently beforehand, and the project suffered what can only be called a political death.
It is designed for military nuclear waste rather than civilian, but many of the challenges are related. Finland is currently the world leader in long-term commercial nuclear waste disposal progress. They produced an excellent video describing the plan. A different form of geologic repository, called a deep borehole, has been proposed by scientists since the s, and has recently gotten much more attention due to advances in drilling techniques.
Deep boreholes involve drilling a hole about meter deep and stacking the spent fuel assemblies there before capping it off. The US DOE planned a Deep Borehole Field Test to better understand the science of this technology option without any actual nuclear waste , but the project was cancelled in due to strong public opposition.
Deep boreholes are being commercialized by a company called Deep Isolation. It can be chemically processed and placed in other reactors to close the fuel cycle. A closed fuel cycle means much less nuclear waste and much more energy extracted from the raw ore. Additionally, this process allows you to convert your waste into chemical forms that are totally immobilized.
The EPA has developed safety training for workers who could come into contact with radioactive material and radioactive wastes.
Workers and managers in any of the industries that produce radioactive waste can take this training to learn more about recognizing and properly disposing of radioactive wastes.
This includes having regulatory agreements to properly dispose of radioactive waste and setting performance objectives for disposal facilities that accept the waste.
Many states have entered into formal agreements with the NRC to exercise authority over the licensing and operation of various activities that produce radioactive waste as well as low-level waste disposal facilities.
These states are known as Agreement States. Should radioactive wastes need to be transported, the NRC in conjunction with the U. Department of Transportation DOT is responsible for regulating the transportation of wastes to storage and disposal sites. Radioactive Waste Transportation This website provides information on how radioactive materials are shipped in the United States. The DOE also manages certain closed disposal sites, including those designated for uranium milling wastes.
Nuclear Waste Storage This webpage provides information on how the DOE is working towards finding long-term storage solutions for nuclear waste. The DOT oversees the safety and security of hazardous materials during transport.
The spent fuel is dissolved in acid so that the useful chemical elements can be extracted and used to make new fuel. The remaining liquid waste is then converted back into a solid glass , which makes it easier to handle. Most of the solid types of waste are placed into a litre drum and then have a very specific type and amount of cement poured on top. This then flows around the waste and turns it into a strong and solid block that is pretty radiation resistant compared to other materials, like plastic.
Some types of waste are squashed in a specialist machine before cementation. Where liquid waste is turned in to glass, it must meet some quality criteria such as how much power it can give off from the radioactive isotopes. These criteria ensure the waste can be safely stored for a long time. Some of it is so radioactive it gets hot.
Used nuclear fuel contains lots of different radioactive elements and some of them decay very quickly. When they decay, they give off a lot of energy that can be absorbed by their surroundings, making them warm.
Radiation is all around us. It comes from the rocks in the ground, from space and from certain medical procedures such as X-rays.
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