Reprocessing both reduces the volume of spent fuel and provides uranium and plutonium that can be used to produce more energy. However, the U. Moreover, liquid high-level radioactive waste is a by-product of reprocessing, and it must be vitrified, or combined with sand and other materials to form a stable glass. The resulting 'glass' presents the same problem as spent fuel: how can we dispose of it? In theory, geologic disposal offers a multiple-barrier solution.
Spent fuel and high-level waste would be placed in specially-engineered casks, and then interred deep below the earth's surface in a repository built in a geologically-suitable formation. High—level waste will remain radioactive for hundreds of thousands of years but there is no way to guarantee that human-engineered waste packages can effectively contain the waste for that long. Geologic disposal provides a second, natural barrier: rocks that would contain waste after containers fail.
Additionally, by locating the repository deep in the earth, spent fuel and high-level waste would be less vulnerable to sabotage and accidents. However, geologic disposal contains its own risks. At Yucca Mountain, an underground repository could be susceptible to seismic activity, volcanism, and water percolation.
If the radiation were to leak, it could contaminate underground water supplies. The key technical risks associated with Yucca Mountain, as a geological repository are discussed here. Yucca Mountain is a 1,foot high flat-topped volcanic ridge extending six miles from north to south see photo above.
Note: The U. As noted on the map to the right, the NTS was the primary testing location of American nuclear devices bombs , and from to the DOE detonated some nuclear blasts at the site, i. Yucca Mountain is comprised of "tuff," a rock made from compacted volcanic ash formed more than 13 million years ago.
Yucca Mountain has a desert climate and receives about six to seven inches of rain and snow per year. The Mountain has a deep water table. The repository would be built approximately 1, feet below the land surface and 1, feet above the water table. Yucca Mountain was selected as the site for the nation's nuclear waste repository in a process that began in and ended in when Congress amended the Nuclear Waste Policy Act NWPA.
NWPA established a comprehensive policy for permanent geologic disposal of the nation's spent fuel and high-level radioactive waste. The Act laid out a step-by-step process for the government to search, study, select, and ultimately, construct a nuclear waste repository by the year NWPA directed the Department of Energy DOE to choose three potential sites for geologic disposal, analyze them in detail, and select the most suitable for recommendation to the President.
If the President agreed with the recommendation and officially designated the site, the governor of the site's state could veto the decision, but the governor's veto could be overturned by a simple majority in both houses of Congress. All of this was supposed to happen before , when the government had promised to start taking waste from the nation's nuclear power facilities. As a result, Congress decided to select only one site for continued study. There is ongoing debate about whether Yucca Mountain is the nation's best place for a nuclear waste repository.
The DOE maintains that Yucca Mountain was selected because it was consistently ranked as the site that possessed the best technical and scientific characteristics to serve as a repository.
The Department says that Yucca Mountain is a good place to store waste because the repository would be:. However, the State of Nevada and other groups believe politics played a huge role in the decision.
Nevada was the smallest and politically weakest state of the three. As science and technology writer Gary Taubes pointed out, "By choosing Yucca Mountain as the only option for a nuclear-waste facility, Congress put the DOE in an untenable position. In effect, it sent the department out to prove that Yucca Mountain would work as a repository, rather than to do a dispassionate analysis of whether it could work or was the best possible site. A number of interested parties believe Yucca Mountain has certain characteristics that pose a concern for long-term isolation of highly radioactive material.
Yucca's location in an active seismic earthquake region the presence of numerous earthquake faults at least 33 in and around the site and volcanic cinder cones near the site the presence of pathways numerous interconnecting faults and fractures that could move groundwater and any escaping radioactive materials rapidly through the site to the aquifer beneath and from there to the accessible environment.
Would a repository at Yucca Mountain protect public health and safety? Who is responsible for health and safety standards? In , the EPA issued a final safety rule outlining a 10, year limit on radiation containment at the site.
Similarly, the Nuclear Regulatory Commission NRC established 10, year compliance periods that DOE must meet in order to qualify for a license to construct the repository. Under these standards, the DOE is required to prove that spent fuel and high-level radioactive waste would be safely stored at Yucca Mountain for 10, years.
However, in July , the U. Court of Appeals in Washington, D. The State of Nevada had filed suit against the EPA, saying the 10, year period was both insufficient and illegal.
The EPA had been required by law to base the safety standard on the recommendations of the National Academy of Sciences. The Academy, however, said the radiation safety standard should be set when the waste would be at its peak radiation levels - at least , years from the time the waste is sent to Yucca. The EPA must promulgate another rule, or Congress must pass legislation to allow the 10, year standard. Accordingly, in September , the EPA issued new radiation standards for the proposed Yucca Mountain nuclear waste repository.
The final standards are a key public health threshold that public officials will use when determining whether the repository should be built. The EPA took three years to finalize the standards after releasing a draft version in The EPA issued a two-part standard as follows:.
For a comparison, a chest X-ray exposes a person to 10 millirem. Americans receive approximately millirem annually from radiation occurring in the environment, from natural sources such as soil, water, and vegetation, and man-made sources like building materials, televisions, and video terminals. Read the details from EPA or read Read More on this website Despite the ruling on the 10, year standard, the DOE maintains that a repository at Yucca Mountain "will perform in a manner that protects public health and safety.
When studies revealed that there would be much more water percolation, or dripping, within Yucca Mountain than previously expected, engineers designed special titanium drip shields to be placed over the waste canisters. The State of Nevada, however, says that the drip shields and DOE's reliance on waste packages underline the fact that Yucca Mountain is geologically unsuitable for a repository. The State points to the possibility of volcanism and seismic activity, and notes that the area is one of the most geologically active in the country.
The Agency for Nuclear Projects also remarks that "the Yucca repository is the only repository under consideration in the world that is located above the water table, not below it. The Department also maintains that a repository would withstand the effects of an earthquake due to its location far below the earth's surface.
Because vibratory ground motion decreases with depth, earthquakes have much less impact underground than on or near the surface.
On a national level, the DOE says a repository at Yucca Mountain would protect public health and safety by removing nuclear waste from sites around the country and consolidating it into just one place. Nevada lawmakers, however, call this the "one waste, one place" myth. They point out that by the time Yucca Mountain is filled to capacity, nuclear power plants around the country will have produced almost as much waste as they currently store.
The Yucca Mountain repository would have a capacity of 77, tons. In , 46, tons of high-level waste was stored around the country. Nuclear power facilities produce an additional 2, tons of waste a year. How would nuclear waste be transported to Yucca Mountain? DOE also decided in the same ROD to select the Caliente rail corridor in which to examine possible alignments for construction of a rail line that would connect the repository at Yucca Mountain to an existing main rail line in Nevada.
The Rail Alignment EIS considered alternative alignments within the Caliente corridor for construction of a rail line within Nevada The Caliente rail corridor: Waste would be shipped on existing rail lines or highway routes to Caliente, in southeastern Nevada. The rail line would cover a distance of miles and is estimated by the DOE to take 4 years to build at a cost exceeding 1 billion.
In a March supplemental document to the Record of Decision on Caliente, DOE revealed that legal-weight trucks might be used to ship casks of waste on existing Nevada highways for up to 6 years while the rail line is under construction.
Under this scenario, waste shipped on existing rail lines across the U. These intermodal stations would need to be constructed. If the Caliente railroad line is built in Nevada, to transport wast to Yucca Mountain, what impact would it have on the national railroad system? On a national scale, the impacts of the proposed railroad line in Nevada would affect about 25, miles of rail lines in 44 states. In other words, if the proposed Caliente line is built, DOE would make thousands of shipment of waste for at least four decades, if not longer.
Of note, if built the proposed Caliente rail line in Nevada would be the longest new track construction considered in the U.
Major transportation routes have not been formally identified by the DOE. The Energy Department says rail route consideration would involve the distance to be traveled, the number of interchanges between railroads, and operational input from carriers.
For the highway shipments, special Department of Transportation DOT guidelines dictate that waste would travel on Interstate highways, beltways, or bypasses. State and tribal routing agencies, following DOT regulations, may designate alternate highway routes through their jurisdictions. Currently there are no rail routing regulations such as there are for highway routing of radioactive waste, and none are anticipated, according to Nevada transportation expert Robert Halstead.
Rail rights-of-way are privately owned and restrict the regulatory abilities of state, tribal, and local governments. As a result, units of government below the federal level will have only limited input into routing rail shipments of spent fuel.
Federal law requires that the DOT study both dedicated radioactive waste only and general-commerce trains to identify the advantages and disadvantages for each mode of transport. In years - let alone 10, - will Nevada be ruled by a democracy, a tyrant, or nobody at all?
Will people ever try to breach the concrete-sealed tunnels in search of long-forgotten secrets? Current modeling methods can't even begin to answer such questions. For all its uncertainties, the Yucca Mountain plan clearly beats the alternative: leaving the waste where it is. America's high-level nuclear detritus, mostly spent fuel from nuclear power plants, resides at temporary storage areas in 39 states. Three quarters of these sites lie within 50 miles of a major population center.
And they're getting crowded, taking in an additional 2, tons a year. Assuming power plants continue operating under their current licenses, by the nation's glowing garbage will total 60, tons. Spent-fuel rods - foot-long, pencil-lead-thin plutonium cylinders whose radioactivity has decayed to the point that they can no longer sustain a chain reaction - remain extremely hot. To keep them contained, they're relegated to nearby buildings where they cool in concrete ponds filled with water that has been treated to absorb radiation.
In the absence of a permanent repository, these ponds must hold the seething waste much longer than anyone planned. The water in spent-fuel pools reeks of lethal radioactive elements, including white-hot cesium , one of the deadliest poisons on earth.
A single drop can kill half the people in a crowded movie theater within 15 minutes. If one of these pools drained, the superheated fuel rods could catch fire, spewing a cloud of cesium and other lethal isotopes into the sky.
The Chernobyl power plant experienced such a conflagration in - although that accident involved the reactor core, which contains far less fuel than a waste pond filled to capacity. The situation at American reactors is even more perilous because US fuel rods are encased in highly flammable zirconium, which ignites between 1, and 1, degrees Fahrenheit, rather than the less-flammable silicon used at Chernobyl.
Then there's terrorism. Cooling pools are decentralized and not always well guarded. Marauders could blast a hole in the side of a pond or rupture a pipe - never mind what would happen if a fuel-laden jet slammed into a waste-filled building. Before September 11, the endless pursuit of certainty at Yucca Mountain while high-level waste languished in vulnerable tanks looked merely clumsy.
Now it looks unconscionable. Congress created a system designed to err on the side of caution, but left to their own devices, regulators could force Yucca's scientists to spend the next 10, years stuck in a recursive loop of trial and error. This is no time for complacency. Existing waste must be secured immediately. The simplest way to lock down spent fuel is to transfer it to dry casks, shells of concrete and steel several feet thick.
Capable of surviving bombs and missiles, these structures have been used to store overflow from crowded cooling pools. So far, only 4 percent of US waste is contained this way. This may seem like an immense sum, but it's only 3 to 6 cents per kilowatt hour of nuclear-generated electricity.
Yet dry casks aren't built to last, so they're no substitute for permanent storage. Consequently, it's imperative to start moving the waste to Yucca Mountain as quickly as possible. Science historian Naomi Oreskes envisions a kind of pilot project that empties the most vulnerable cooling pools first.
Even a crash program to begin shipping waste to Yucca will take three or four decades, according to the Department of Energy. Spent fuel must lie under water for five years before it's cool enough to move safely. Moreover, the repository itself is far from complete, with processing centers still to be built and miles of tunnels to be bored.
An estimated 93, shipments by truck and rail will be needed to move radioactive rubbish sealed in accident- and terrorist-proof containers. That's bound to take time. Meanwhile, Yucca Mountain's tunnels should remain unsealed indefinitely while research continues. This would make it possible to relocate the waste elsewhere, should some fatal flaw be discovered in the mountain years or decades from now. Even this plan won't buy any breathing room. At the rate radioactive waste is accumulating, Yucca will be filled to capacity in less than 20 years.
For the time being, Americans have to face an unpleasant fact: Forecasting the future is an iffy business that can never provide percent certainty. Thus, the WIR Process has the cart before the horse, which is to be forgiven since this subject is, at best, opaque to Congress and the public.
This should change the path forward for waste disposal dramatically, especially the cost and schedule. We can safely dispose of these wastes using existing technology at existing sites for a fraction of the cost and time that Yucca Mt would take. Alternative facts aside, we really cannot afford to do dumb things that cost hundreds of billions of dollars.
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