- A brief sketch of Urama grammer with special consideration of particles marking agency, aspect, and modality.
- Dirichlet Forms: Lectures given at the 1st Session of the Centro Internazionale Matematico Estivo (C.I.M.E.) held in Varenna, Italy, June 8–19, 1992.
- UC Berkeley.
- Lonely Planet Dominican Republic (6th Edition);
- 2050: Designing Our Tomorrow.
- Mark of the Rose.
After spending decades and billions of dollars to research potential sites for a permanent disposal site, including at the Yucca Mountain site in Nevada that has a license application pending to authorize construction of a nuclear waste repository, the future prospects for permanent disposal remain unclear. Two federal agencies—the Nuclear Regulatory Commission NRC and DOE—are primarily responsible for the regulation and disposal of the nation's spent nuclear fuel and high-level radioactive waste.
The Nuclear Waste Policy Act of directed DOE to investigate candidate sites for disposing of spent nuclear fuel and high-level radioactive waste. It also directed the President to consider whether a separate disposal facility would be required for the defense-related nuclear waste. Since then, several decisions have affected U. Since DOE terminated its licensing efforts at Yucca Mountain in , there has been no consensus between the Administration and the Congress on a path forward for managing commercial or defense nuclear waste.
However, two independent entities have recently submitted license applications to the NRC for the consolidated interim storage of spent nuclear fuel—one located in Texas and one in New Mexico—a process which may take several years. If DOE were to resume the license review for the Yucca Mountain repository and select and develop one or more sites for interim storage, the process would be challenging for a number of reasons, including the following:.
What about the waste?
Power plants in 33 states store nearly 80, metric tons of radioactive waste. In , the Department of Energy applied to the Nuclear Regulatory Commission to build an underground repository for this waste at Yucca Mountain in Nevada. DOE planned for decades to store defense and commercial nuclear waste in a single repository in Yucca Mountain, Nevada. But we found that DOE' Based on its prior work, GAO found three key challenges related to the transportation of spent nuclear fuel: legislative, technical, and societal.
TL;DR (quick summary)
Legislative challenges. As GAO reported in November , August , and October , DOE does not have clear legislative authority for either consolidated interim storage or for permanent disposal at a site other than Yucca Mountain. Specifically, p Spent nuclear fuel—the used fuel removed from nuclear power reactors—is expected to accumulate at an average rate of about 2, metric tons per year in the United States.
This spent nuclear fuel is mostly stored wet, submerged in pools of water. However, since pools have been reaching their capacities, owners and generators of spent nuclear fuel typically utilities and reactor operators hav In examining centralized storage or permanent disposal options, GAO found that new f The future of the Yucca Mountain project in Nevada--originally designated for permanent storage of nuclear waste--is uncertain.
Since , the Department of Energy DOE has spent billions of dollars to evaluate the Yucca Mountain site for potential use as a nuclear waste repository. Spent nuclear fuel--considered very hazardous--is accumulating at commercial reactor sites in 33 states. In June , DOE submitted a license application for the repository, but in March moved to withdraw it. However, the Nuclear Regulat DOE and the Navy int High-level nuclear waste--one of the nation's most hazardous substances--is accumulating at 80 sites in 35 states. The United States has generated 70, metric tons of nuclear waste and is expected to generate , metric tons by The Cold War arms race created a buildup of nuclear waste in the United States that needs to be cleaned up.
Yet the Department of Energy program responsible for this effort categorizes most of its work in a way that does not adequately involve independent experts and DOE senior leadership.
It also has not DOE's Office of Environmental Management addresses contamination at nuclear weapons production sites. A key attribute identified was that the Department of Energy DOE had spent significant resources to carry out design, engineering, and testing activities on the Yucca Mountain site and had completed a license application and submitted it to the Nuclear Regulatory Commission, which has regulatory autho More demand for electricity and concerns about greenhouse gas emissions have increased interest in nuclear power, which does not rely on fossil fuels.
However, concerns remain about the radioactive spent fuel that nuclear reactors generate. DOE has about 14, employees to oversee the work of more than 93, contractor employees. Skip Navigation. Advanced Search. In , President Reagan found that there was no basis to conclude that a separate defense—only waste repository was required. A DOE evaluation concluded that cost efficiency favored a commingled repository. In , DOE terminated its licensing efforts at Yucca Mountain, stating that a geologic repository at Yucca Mountain is not a workable option.
In , DOE announced a new strategy for disposing of spent nuclear fuel and high-level radioactive waste. This included temporarily storing waste at centralized locations and then commingling commercial and defense waste in a single repository—to be operational by —at a site other than Yucca Mountain.
DOE recommended creating a separate waste management organization to use a phased, adaptive, consent-based approach to siting and developing the new repository.
Also in , in response to a lawsuit brought against NRC for suspending its license review in , a federal appeals court ordered NRC to resume the Yucca Mountain licensing process. In , President Obama found that a separate repository for defense-related radioactive waste was required. DOE reported that defense waste is smaller in volume, less radioactive, and thermally cooler than commercial spent nuclear fuel, stating that a defense repository may be easier to develop.
According to DOE, Congress did not provide this funding. As of February , Congress has not directed funding for the license application to resume. If DOE were to resume the license review for the Yucca Mountain repository and select and develop one or more sites for interim storage, the process would be challenging for a number of reasons, including the following: Social and political opposition. Currently, nuclear waste created in the US is stored underwater in spent fuel pools near nuclear power plants.
Assuming the DOE eventually licenses the Yucca Mountain repository in Nevada, this waste will eventually be stored deep underground. Since Yucca Mountain is on the Nevada test site, and since the area is geologically stable, the location is suitable. However, the repository is designed to a certain capacity of nuclear waste.
Nuclear Fuel Cycle
If it ever opens, it will fill quickly thanks to the build-up of waste throughout the last few decades and another repository will need to be constructed. However, there are ways around this. The Finns are way ahead of the rest of the world, and are responsibly building a safe deep geologic repository for all their waste. It can be chemically processed and placed in advanced fast reactors which have not been deployed on any major scale yet to close the fuel cycle.
A closed fuel cycle means much less nuclear waste and much more energy extracted from the raw ore. France currently recycles spent fuel, although they only recycle one time before disposal.
The US had a recycling program that was shut down because it created Plutonium, which could be used to make a nuclear weapon. Were some plutonium diverted in the recycling process, a non-nuclear entity could be one step close to building a bomb. However, under programs such as the now stalled GNEP [wikipedia] , where only countries who already have nuclear weapons recycle, proliferation-free waste recycling can exist. Since the many of the largest energy users are already nuclear weapons states, a massive expansion of nuclear could be done there with no additional proliferation concerns whatsoever.
You will find more discussion of proliferation on our nonproliferation page. Please remember to contact us with your comments or questions. The longest living nuclides in nuclear waste are the ones that can be used as fuel: plutonium and the minor actinides. If these materials are burnt in fuel through recycling, nuclear waste would only remain radioactive for a few hundred years, as opposed to a few hundred thousand. This significantly reduces concerns with long-term storage.
See Also See our main recycling page for a more thorough discussion of recycling. This would allow for recycling and breeding without creating any plutonium or minor actinides whatsoever. Fission products are still created, of course, and some of them are quite long-lived, but reducing the minor actinides is a benefit of Thorium. Nuclear reactors are typically loaded with Uranium Oxide fuel, UO 2. Neutrons are introduced to the system, and many of them are absorbed by uranium atoms, causing them to become unstable and split, or fission, into two smaller atoms known as fission products.
Sometimes, the uranium absorbs a neutron and does not fission, but rather transforms to a heavier isotope of uranium, such as U U beta-decays to Np, which in turn beta-decays to Pu The heavier nuclide may then absorb another neutron to become an even heavier element. These heavier atoms are known as transuranics.
U.S. GAO - Key Issues: Disposal of High-Level Nuclear Waste
Nuclear waste, with regard to nuclear reactors, is the collection of nuclides left over after a reactor has extracted some energy out of nuclear fuel. Many of the isotopes are very radioactive for a very long time before they decay to stability. The radioactivity causes the spent nuclear fuel to continue emitting heat long after it has been removed from the reactor.
A few of the radioactive isotopes in the mix of spent fuel are gaseous and need to be carefully contained so that they do not escape to the environment and cause radiation damage to living things. Other types of nuclear waste exist, such as low level waste from other applications.
This discussion focused on high-level waste HLW , the spent nuclear fuel from nuclear power reactors. Toggle navigation. Concepts Learn about nuclear energy What is Nuclear Energy? What is Radioactivity? What is Nuclear Engineering? What is radioactive dose? Nuclear Reactor Risk Assessment? What is a nuclear fuel cycle? Computing the energy density of nuclear fuel Barn Jams! What about the waste? TL;DR quick summary Nukes produce unbelievably little waste compared to other energy sources.