The radioactivity of nuclear waste naturally decays, and has a finite radiotoxic lifetime. Within a period of 1,, years, the radioactivity of HLW decays to that of the originally mined ore. Its hazard then depends on how concentrated it is. By comparison, other industrial wastes e. Most nuclear waste produced is hazardous, due to its radioactivity, for only a few tens of years and is routinely disposed of in near-surface disposal facilities see above. International conventions define what is hazardous in terms of radiation dose, and national regulations limit allowable doses accordingly.
Well-developed industry technology ensures that these regulations are met so that any hazardous waste is handled in a way it poses no risk to human health or the environment. Waste is converted into a stable form that is suitable for disposal. In the case of HLW, a multi-barrier approach, combining containment and geological disposal, ensures isolation of the waste from people and the environment for thousands of years.
Radioactive Waste Management. Radiation scientists, geologists and engineers have produced detailed plans for safe underground storage of nuclear waste, and some are now operating. Geological repositories for HLW are designed to ensure that harmful radiation would not reach the surface even in the event of severe earthquakes or through the passage of time. The designs for long-term disposal incorporate multiple layers of protection. Waste is encapsulated in highly engineered casks in stable, vitrified form, and is emplaced at depths well below the biosphere.
Such long-term geological storage solutions are designed to prevent any movement of radioactivity for thousands of years. Whilst the timeframes in question preclude full testing, nature has provided analogous examples of the successful storage of radioactive waste in stable geological formations. About two billion years ago, in what is now Gabon in Africa, a rich natural uranium deposit produced spontaneous, large nuclear reactions which ran for many years.
Since then, despite thousands of centuries of tropical rain and subsurface water, the long-lived radioactive 'waste' from those 'reactors' has migrated less than 10 metres. Storage and Disposal of Radioactive Waste. Because it is widely accepted that producers of radioactive waste should bear the costs of disposal, most countries with nuclear power programmes make estimates of the costs of disposal and update these periodically. For LLW the costs are well-known because numerous facilities have been built and have operated for many years around the world.
For HLW, cost estimates are becoming increasingly reliable as projects get closer to implementation. Based on the estimated total costs of managing nuclear waste, many countries require that the operators of nuclear power plants set aside funding to cover all costs. Different mechanisms exist in different countries. Although the sum already deposited in dedicated funds is high, the costs of waste management do not drastically increase the price of electricity. Thus, although the absolute costs of waste management are high, they do not render the nuclear fuel cycle uneconomic, because of the high ratio of revenue earned to waste volumes produced.
Radioactive Waste National Policies and Funding. The option of disposal of waste into space has been examined repeatedly since the s. This option has not been implemented and further studies have not been performed because of the high cost and the safety aspects associated with the risk of launch failure.
International Nuclear Waste Disposal Concepts. Transmutation is the process of transforming one radionuclide into another via neutron bombardment in a nuclear reactor or accelerator-driven device. The objective is to change long-lived actinides and fission products into significantly shorter-lived nuclides. The goal is to have waste that becomes radiologically harmless in only a few hundred years.
Transmutation is not feasible for all of the waste produced in the past or to be produced. Transmutation may be able to reduce waste quantities, but it will do so only to a certain extent and therefore not eliminate the need for some means of ultimate disposal. Research on transmutation is, however, ongoing. One of the technical issues is to isolate each nuclide partition so that it can then be irradiated, otherwise the process is likely to create as much waste as it destroys.
Cost aside, it is likely that the benefits of transmutation will not compensate the burden of additional required operations for separating and transmuting only part of the nuclides. HLW is kept in secure nuclear facilities with appropriate protection measures. Most HLW produced is held as stable ceramic solids or in vitrified glass form, designed to ensure that radioactive isotopes resulting from the nuclear reaction are retained securely in the glass or ceramic. Their structure is such that they would be very difficult to disperse by terrorist action, so that the threat from so-called 'dirty bombs' is not high.
The US Nuclear Regulatory Commission NRC has responded to suggestions that spent fuel is vulnerable to terrorist actions and should be put into dry storage casks after five years: "Nuclear power reactor spent fuel pools are neither easily reached nor easily breached. Instead, they are strong structures constructed of very thick steel-reinforced concrete walls with stainless steel liners. Frankel, materials scientist, Ohio State University. Credit: US Department of Energy. These underground tanks in Hanford, Washington, were built in the s to store liquid radioactive waste from plutonium production.
Today, the contents have been transferred to newer tanks in preparation for vitrification. Widespread storage Tens of thousands of metric tons of radioactive spent nuclear fuel sit in steel-and-concrete storage casks cutaway at nuclear power plants across the US map as they await permanent disposal.
Credit: Pacific Northwest National Laboratory. Meline pours a sample of molten glass to study corrosion in vitrified nuclear waste. Related: Tank Troubles. Vitrification of nuclear waste seems to be well established by now, but actually it still faces complex problems.
You might also like Nuclear Power. Proposed nuclear waste storage materials may have a corrosion problem. Radioactive Waste Safety. Tank Troubles. Share X. To send an e-mail to multiple recipients, separate e-mail addresses with a comma, semicolon, or both.
Title: As nuclear waste piles up, scientists seek the best long-term storage solutions. Submit Sending Purniah March 30, AM. Its well known that the spent fuel taken out of a reactor contains a lot of useful material.
Unused fuel, Plutonium and radioactive fission fragments which can be used for medical treatment etc. If these are removed then the remaining waste is very less. So it makes sense to reprocess the spent fuel. Mike Keller March 30, PM. Reprocessing is an ideal that more or less guarantees no solution will emerge. Get rid of the stuff, as in deep underground. Anja May 18, PM. But it does not disappear when you bury it underground. You just don't see it.
But we don't know what it will do underground overtime. Stan October 26, AM. If you reprocess the spent fuel then there is no waste to dispose of. Right now we use less than 0.
Put spent waste in a fast actinide burner and you can recover essentially ALL of the energy. We have enough uranium already mined to power the planet for the next years. And there is NO long term waste. After a few centuries a period of time that it's easy to store something for you are left with silver, palladium, and rhenium, along with other valuable industrial elements.
I wish I had the 'problem' of having a few million metric tons of palladium Phil March 30, AM. Partially spent nuclear fuel will be used as a fuel source for Generation 4 reactors being developed now by Bill Gates' TerraPower and others. It will supply electricity for decades without mining any more uranium. Dry Cask storage is safe and adequate for the near future.
In my opinion and that of many others permanent disposal is costly and not necessary. Tony April 19, PM. Yes, TerraPower is by far the best way to use spent nuclear materials, e. Or we could have engineers manage the effort and actually get something accomplished. The solution does not have to be perfect, it only has to be good enough for a couple of hundred years.
At that point the radiation levels are reasonably low. Worrying about the disposition of plutonium in the distant future is a classroom exercise. TptDac April 1, AM.
I have given thought to the issue of what kind of people could run a successful nuclear waste disposal project. I spent a fair part of my career as a scientist working on such projects. When the scientists were in charge, the funding tended to be a feeding trough for people who did what they wanted to do anyway.
When the engineers were in charge, things were more focused on the end result. There was always some component of basic science that was actually needed to attain the end result. I am not impressed with this article. It presents a happy picture Wow, now we know what to do! Look up the history of project failures, going back about four decades or so e. The article should have included something about the long history of failures, especially those related to vitrification.
Bart Ziegler May 19, AM. Excellent comment. Tom March 30, PM. This industry has never known what to do with the waste. They are idiots for ever making any of it. Nature out of place.
Don't blame the industry. The federal government promised to figure out the waste disposal issue. These researchers complain about kicking the waste "problem" down the road. The truth is that their own remarks, and articles like this, make it more likely that it will continue to be kicked down the road. The nuclear waste "problem" is purely political. It has been technically solved for a long time. The fact is that any risks long-term as well as shorter term associated with nuclear waste are tiny compared to those associated with other industries' and energy sources' pollution and waste streams.
Even with all the supposedly significant issues these researches go on about, the long-term risks of other waste streams are orders of magnitude larger. It is the only industry that is containing all its wastes and is ensuring that they remain contained for as long as they remain hazardous. NRC has concluded that Yucca Mountain would meet that impeccable, unprecedented requirement that no other waste streams come close to meeting.
Other industries just release their wastes and toxins directly into the air, simply heap them into piles like coal ash or carelessly shallow-bury them. Depleting earth's reserves of valuable hydrocarbons, destabilizing the planet's climate, and lacing soil and water all over the world with toxins like mercury and arsenic; now THAT's a gift to future generations! If one is concerned about overall public health and safety, as well as the climate, the way to help is not to nitpick about tiny nuclear-power-related risks or try to make tiny nuclear-related risks even smaller.
Even solar and wind power pose larger risks than the ones these researchers seem to be so concerned about. The only real issue nuclear power has is cost, and almost all research efforts should be directed at bringing nuclear power costs down. THAT is how you reduce public health risks. Dennis Huber March 31, PM. It is really straightforward to resolve the spent fuel issue. Reprocess the spent fuel into four product streams - transuranics that go to a burner or breeder reactor, fission products that are further separated into short lived less than 33 years that can be vitrified and stored for years or so at Yucca Mountain, and the seven bad actor fission products with long half lives that need to be sent to the burner reactor.
The fourth stream - the rest of the "waste" - is Uranium dioxide, and the deficit mass from the fission products and transuranics can be filled with weapons grade U or Pu from US or former Soviet Union weapons such that the resulting average enrichment is sufficient to use the entire lot to power another nuclear reactor without having to mine additional uranium for an extended time.
We should eliminate our wasteful once-through practice and deal with the problem we have created, not pass it onto the next generation. Certainly I have simplified this: there are small issues with this approach few technical, mostly regulatory , but it is much better than the alternative - which is continue to do nothing.
Noel Wauchope March 30, PM. Look, this is a really informative and interesting article. Steven Curtis March 30, PM.
Great article, however, recycling should be explored more in-depth. Purniah is right about recycling commercial used nuclear fuel, however, taking out medical radioisotopes must be done quickly for them to be useful.
No process plans to do so yet, but it would be great if it could happen. Nevertheless, getting the remaining power from material currently considered waste should not be ignored. Shane Broussard March 31, AM. We should be recycling the fuel as much as possible. Continuing to study the problems and doing nothing is what has been done for decades.
There is no way to guarantee any storage solution for millenia. This is also highly dangerous, but it can be stored in special canisters because it does not generate much heat. The rest is made up of vast quantities of what is called low-level and very low-level waste.
This comprises scrap metal, paper, plastics, building materials and everything else radioactive involved in the operation and dismantling of nuclear facilities. The consensus is that about 22, cubic metres of solid high-level waste has accumulated in temporary storage but not been disposed of moved to permanent storage in 14 western countries, along with unknown amounts in China, Russia and at military stations. A further , cubic metres of intermediate waste is being stored, and about 3.
About 34, cubic metres of new high-level and intermediate waste is generated each year by operating civil reactors, says the WNA. The US, with 59 nuclear power plants comprising 97 working civil reactors , each generating at least several tonnes of high-level waste per year, has about 90, tonnes of high-level waste awaiting permanent disposal, according to the US Government Accountability Office. Although it is impossible to come up with a global total because of differences in how quantities are measured and reported, and with some inventories kept secret, other countries harbour significant amounts of waste as well.
In the early days of nuclear power, waste of any sort was barely considered. British , American and Russian authorities, among others, dumped nuclear waste — including more than , tonnes of low-level waste — at sea or in rivers.
Since then, billions have been spent trying to identify how best to reduce the amount produced and then store it for what may be eternity. Many ideas have been investigated, but most have been rejected as impractical, too expensive or ecologically unacceptable. Vertical boreholes up to 5, metres deep have also been proposed, and this option is said by some scientists to be promising. But there have been doubts, because it is likely to be nearly impossible to retrieve waste from vertical boreholes.
Two scientific developments excite nuclear scientists. One is to build a new generation of advanced fast neutron reactors , which would use the high-level waste as fuel. But even though such reactors can reduce the degree of hazard the waste poses, they do not solve the issue entirely.
The other technology that could reduce waste, known as transmutation , aims to reduce radiotoxicity by using lasers to change the composition of dangerous waste. After decades of civil nuclear power and billions spent researching different geological sites and ways to best dispose of the waste, the problems are both technical and political, and the consensus of governments and industry is that deep burial is the best solution — at least for the moment.
Yet, so far, no country has managed to build a deep repository for high-level waste. The US has come closest with a single deep repository.
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