This has also left users of nuclear products such as hospitals and universities scrambling to find a place to dispose of their radioactive residue. So now the waste from the majority of reactors on the east coast and Midwest typically sits alongside the spent nuclear fuel in dry casks on-site. In terms of safety, it's the best that can be done at present. Somewhere where there were armed security officers with concrete buildings," Andersen says.
It originally stated that the Monju fast-breeder reactor used molten salt coolant. Thanks to bhoglund for pointing out the error. David Biello is a contributing editor at Scientific American. Follow David Biello on Twitter.
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Support science journalism. Knowledge awaits. Since nuclear waste can remain radioactive for hundreds of thousands of years, the choices that we make today affect future generations.
Thus, the issue of nuclear energy is a moral one. Many argue that people living today should deal with the burdens of nuclear power since we will be reaping the majority of the benefits. 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.
In addition, other design characteristics of these pools Such characteristics can include having the fuel in the pool partially or completely below grade and having the pool shielded by other plant structures.
A report released on 25 June by the National Academy of Sciences concludes that if a dirty bomb attack were to occur, "the casualty rate would likely be low, and contamination could be detected and removed from the environment, although such cleanup would probably be expensive and time consuming. The International Atomic Agency IAEA has identified medical and industrial radioactive sources as posing considerable concern in terms of potential terrorist threats from their use in dirty bombs.
The need for stronger controls to prevent the theft or loss of control of powerful radiological sources and hence ensure their safety and security has been highlighted as of paramount importance. Security of Nuclear Facilities and Material. Radiation emitted from man-made radionuclides is exactly the same form as radiation emitted from naturally-occurring radioactive materials namely alpha, beta, or gamma radiation.
As such, the radiation emitted by naturally-occurring materials cannot be distinguished from radiation produced by materials in the nuclear fuel cycle. Most elements have a radioactive form radioisotope and many of these occur naturally. We live our lives surrounded by naturally-radioactive materials, and are constantly bathed in radiation originating from rocks and soil, building materials, the sky space , food, and one another.
A typical background level of exposure is millisieverts per year. Some people are exposed to lifelong natural background levels which are higher than this. Radioactive Waste — Myths and Realities Updated February There are a number of pervasive myths regarding both radiation and radioactive waste. Some lead to regulation and actions which are counterproductive to human health and safety.
Some of the more commonly expressed views and concerns include: 1. The nuclear industry still has no solution to the 'waste problem'. 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. Get off the pot and put this stuff in Yucca mountain.
Or why not just drop these storage containers into the ocean above the Mariana' Trench? Cowan March 31, AM. The Vermont Yankee casks in the page-top photo could I suppose be considered a one-deep pile. Years ago, both gas and uranium prices were much higher, and government's loss was accordingly greater. Otherwise said, it's down fold. Dallas March 31, PM. Or we could consume all that waste in a next gen reactor and provide years of safe, carbon free electricity and process heat.
Jacob D. Paz March 31, PM. Both the scientific community and the state of the Nevada have challenged the proposed high nuclear waste repository at Yucca Mountain, Nevada based on scientific and legal grounds.
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