Issue Date: May 5, 2008
The Forever Waste
LATE NEXT MONTH, the Department of Energy intends to submit to the Nuclear Regulatory Commission a permit application to build a nuclear waste repository at Yucca Mountain in Nevada. The application will be long, complex, and incomplete. Missing will be a radiation standard needed to protect humans from exposure during the millennia that the high-level radioactive waste and spent fuel will remain dangerous after being left in the deep geologic repository.
The missing radiation regulation had been developed by the Environmental Protection Agency, but it was dismissed by a U.S. Court of Appeals' decision in 2004. Time was the problem.
As the appellate court wrote in the first words of its decision, "Having the capacity to outlast human civilization as we know it and the potential to devastate public health and the environment, nuclear waste has vexed scientists, Congress, and regulatory agencies for the last half century."
The court's statement throws a spotlight on the inability of the past two generations of scientists and politicians to craft a protective and publicly acceptable fate for this waste. It mirrors waste debates that stretch back to the dawn of the nuclear age.
But the lack of a standard is just another roadblock in the path to open Yucca Mountain, joining a host of other hurdles: DOE missteps, congressional interference and budget cuts, falsified data, opposition and litigation by Nevada, and the physical geology of the mountain itself. Intended by law to accept waste in 1998, the Yucca Mountain repository will not open until at least 2020, if it opens at all.
As Yucca Mountain recedes further into the future, nuclear supporters and opponents are taking a new look at radioactive waste solutions, what went wrong in Nevada, and what should be done with nuclear waste. Specifically, they are asking, if no permanent repository can lock this waste away, how should it be handled to protect future generations?
The waste dilemma takes on added significance in light of the threat of climate change and the role a nuclear power renaissance could play in reducing carbon dioxide emissions. But without some sort of meaningful plan for managing current spent nuclear fuel, the world seems unprepared to accept another round of nuclear power plants.
FOR NOW, however, the nuclear nations seem content to continue to punt their nuclear waste responsibilities to the future. Some scientists and policymakers agree, saying a final decision on nuclear waste should be left to future generations no matter what path is picked; others say it is at best irresponsible, at worst a crime, to leave the waste to be addressed by generations not yet born.
"In the late 1970s, we began this process, and eventually Congress selected Yucca Mountain," says Robert W. Fri, a visiting scholar at the nonpartisan think tank Resources for the Future and chair of a National Academy of Sciences (NAS) committee whose study led to the court's decision dismissing the EPA standard.
"The idea was that we created this stuff and we are going to solve this problem," Fri says. "But it turns out to be very hard to do, and this waste is going to be around for a long time. In my judgment, it is very hard to say conclusively that we know enough about the geology of Yucca Mountain or anyplace else, or for that matter any other treatment technology, to say for sure that we've got the answer."
Milton Russell, economics professor emeritus at the University of Tennessee, a former EPA assistant administrator, and a policy analyst who has long studied DOE cleanups, adds, "If we spend large amounts of our political capital and our wealth to ensure that not one molecule of current nuclear waste is harmful 10,000 or more years from now, we will use up this generation's and next's potential investments and consumption.
"Don't get me wrong," Russell continues, "I am concerned about waste. But we can't be stewards for people far into the future. We don't know what life they will live or what science and technology they will have."
Seeing nuclear ethics in a very different light is Kristin Shrader-Frechette, a University of Notre Dame professor in the departments of biological sciences and philosophy and an authority on nuclear issues and ethics. "If we won't consent to bear the burdens of nuclear waste today, we have no grounds to believe future generations will, especially without benefits or compensation," she stresses. "One generation cannot transfer its mortgage or its debt to a generation unborn."
"Fifty years of energy for 500,000 years of waste" is how Dan Hirsch, a nuclear policy analyst and founder of the nonprofit antinuclear group Committee to Bridge the Gap, views nuclear energy.
"It is unethical to continue to produce extraordinarily toxic waste through processes that benefit our generation when we have no solution to protect generations yet to come," Hirsch says. "It is like building a ship in your basement without a thought of how you are going to get it out. We should not produce a single curie more until we have a way of protecting future generations."
The EPA regulatory approach set a radiation exposure cap for the first 10,000 years after the spent fuel was placed in the mountain; the court said that that time frame was far too short and that the cap should be premised on when the exposure to the waste is likely to occur.
The proper timescale, the court said, is 1 million years, citing a 1995 NAS study that Congress had ordered EPA to use for its exposure standard. One million years works out to more than 25,000 human generations.
After involving some 50 scientists, the academy's National Research Council determined that EPA should set a compliance period on the order of 1 million years. However, EPA chose not to do so, pointing to the difficulty and "impracticality" of writing a regulatory decision-making tool that covers a million years. Instead, it picked 10,000 years. The court was not swayed and invalidated EPA's standard.
Its decision threw EPA's regulation into turmoil, and it also underscored the inherent difficulty in isolating nuclear waste basically forever.
For the past few decades, the debate over nuclear power and waste has been mostly technical—safety, fuel pools, canister design, transportation, interim waste storage, spent-fuel reprocessing, and so on. Left wanting is a discussion over ethics and who benefits and who pays.
In clear legalistic terms, the appellate court laid out the nuclear problem in plain but colorful language. The court noted that the "harmful consequences" of radioactive waste "persist for time spans seemingly beyond human comprehension," pointing specifically to radionuclides with a half-life of 17 million years (iodine-129) or 2 million years (neptunium-237), which will be in the repository. The court also underscored the dimension, saying U.S. nuclear waste quantities will grow to more than 100,000 metric tons over the next 40 years.
FOR THESE reasons, the court has made it clear that it will block the repository's future until EPA follows the advice of the NAS study.
EPA's setting of a long-term standard is important because the repository will leak. According to DOE, which designed the repository and by law must build and operate it, maximum exposure to the radiation will occur 480,000 years after Yucca Mountain is sealed. In its environmental impact statement, the department said the leak will contaminate groundwater 11 miles from the repository at a specific place that is currently used by humans.
At that place the dose to a hypothetical "maximally exposed individual" would be between 120 and 150 millirems per year, DOE said. However, a host of scientists disagree—with both when the waste will leave the repository and at what level the radioactive contamination will be.
In 2005, EPA proposed a new regulation with a 15-millirem exposure cap for the first 10,000 years after waste is disposed, which is identical to the invalidated regulations. For generations over the following 990,000 years, however, the agency proposed a 350-millirem annual median exposure limit. EPA has yet to issue a final regulation, and when it does, there will be a long line waiting to sue.
The 350-millirem limit coincides with a level of cosmic radiation naturally received annually by a person who lives at very high elevations, such as in Denver. However, it is a median exposure dose, not a maximum, which is unusual for an environmental regulation. On its face, it is far weaker than the 10,000-year 15-millirem limit, but that is only part of the story.
"Half the population will be allowed to exceed the dose," Shrader-Frechette notes, adding that the regulation shows the willingness of one generation to devalue the environment for another. "This isn't just intergenerational inequity; it is also scientific sleight of hand. Pollution regulations are not set based on median personal exposure. We should believe in equal treatment for an entire population," she says.
Projections by several organizations have estimated that this exposure will result in a 1-in-36 risk of cancer for people at the high end of the distribution.
The problems with Yucca Mountain, many believe, stretch back to its selection. That has long been the view of nuclear opponents and the State of Nevada, but now they are quietly being joined by some nuclear advocates.
MORE THAN 20 years ago, DOE considered several sites as possible geological repositories in both the eastern and western U.S. With time, Study, and growing objections by residents and members of Congress, sites were eliminated. Congress ended the process altogether in 1987, even though site characterizations were incomplete. It passed a law cutting remaining candidate sites to one Yucca Mountain. At the time, the legislation earned the tag from some in Congress as the "Screw Nevada Act."
As DOE went ahead with further site characterization studies at Yucca Mountain, significant problems emerged, and, most important, DOE found that its hopes for the dry Nevada landscape did not hold up. A great deal more water had historically flowed through the mountain than was thought. Consequently, the waste containment design shifted from reliance on geology to a focus on the metal waste canister.
Because of the politically driven selection process, DOE had to "back fit" the design to match the site's needs, says Arjun Makhijani, a physicist and director of the nonprofit Institute for Energy & Environmental Research. His biggest concern is the canisters. Due to thermal heat from waste cesium and strontium, the canisters and tunnels will be physically hot for the first 100-plus years, he notes. The result will be heat and humidity, which will lead to rust in the presence of oxygen, Makhijani says. He believes the canisters will break down quickly and the waste will begin exiting the mountain in hundreds of years.
For this reason, Makhijani wants Yucca Mountain reconsidered. "We need 10 to 15 more years of scientific homework before we can select another site," he says, stressing that geology and the canister material should be considered together to make for a redundant protective system.
Makhijani's view is shared by Thomas B. Cochran, a physicist and senior scientist with the Natural Resources Defense Council. He too urges a search for a second repository. Yucca Mountain, he suggests, should be used for further testing and for storing defense waste, not commercial reactor spent fuel, as a face-saving measure.
The geological selection process has also been criticized by Richard A. Meserve, president of the Carnegie Institution and a former chairman of the Nuclear Regulatory Commission.
"The selection process should have been transparent," Meserve said, speaking to attendees of a nuclear waste conference last January at Vanderbilt University. "The process established a grievance by Nevada and ensured its opposition."
Meserve added that Yucca Mountain is "certainly threatened at this moment. If Yucca Mountain fails, we may rethink this approach." He also noted that both Democratic Party presidential candidates oppose the repository, that appropriations have been cut, and that there are "great problems with licensing."
NEVADA OFFICIALS have said they will sue once EPA issues a final radiation regulation, and so have environmental groups. The Nevada officials have also said they intend to initiate up to 500 separate challenges to DOE's expected 8,000-page license application once it is filed.
In light of this opposition—even without technological questions—permanent nuclear waste disposal is decades off at best, experts point out. Meanwhile, a host of waste alternatives are being discussed with very different impacts on future generations.
For the nuclear power industry, the waste is "safe and secure" right where it is, resting in pools or dry casks, on-site next to the reactors where it was created, says Steven Kraft, the Nuclear Energy Institute's (NEI) senior director for used fuel management. "The Nuclear Regulatory Commission says it can stay there for 100 years, and it can probably stay a lot longer."
The 58,000 tons of spent fuel already generated could fit on a football field, Kraft says. "This is nothing," he notes, "compared to the sludge piles you get from coal-fired power plants.
"But we are obligated as a society to at least begin to do something with it," he adds, "and we are going to do that by siting a voluntary interim storage facility in a community that wants our business." Kraft says NEI has been approached by officials in three or four communities that want to be home to a storage facility. He won't divulge any names.
NEI wants the interim storage facility to be privately owned but operated by the government, Kraft says. Most important, the federal government should take ownership of the spent fuel, he says, which is now the power generator's responsibility. But, Kraft explains, the nuclear power industry wants to "get the flywheel turning" for a future of nuclear power.
First, the industry intends to build a half-dozen new nuclear power plants, driven by electricity demand, economics, and federal government support. But for initial construction to take place, he says, the industry has to have a plan for handling high-level waste and has to show that progress is being made in moving some of the waste from at least one plant.
But for a huge growth of nuclear power—the nuclear renaissance—much more must occur. The renaissance would include factories to reprocess spent fuel and a system of 10 to 30 fast-neutron plutonium "burner" reactors to "recycle" the spent fuel and waste and generate more electricity. Such fast-neutron reactors have not advanced beyond a small number of unsuccessful demonstration projects in several parts of the world, however. The system would cost billions of dollars and would lead to nonproliferation fears from the separation of plutonium. Nevertheless, DOE has initiated several research projects and remains strongly committed (C&EN, June 18, 2007, page 48).
But as this movement by the nuclear power industry and DOE goes forward, waste keeps building up. Meserve notes there is value in the waste and it is time to rethink how we see spent fuel.
"Traditionally, generations who obtained a benefit should retain the cost," Meserve said at the Vanderbilt meeting. "On the other hand, is it rational to spend billions of dollars to protect a hypothetical person hundreds of thousands of years in the future? Seems to me we need to consider the scope and nature of the risk, as well as the limited number of people affected."
Meserve has warned that a repository may be seen in the future as a "mine" holding material of value to future generations. Sealing the waste in a permanent repository, he said, is "paternalistic" on the part of the current generation. It removes an option from generations yet to come to be able to extract plutonium from the waste to use as fuel.
Russell agrees. He backs what he calls "revolving stewardship" for spent fuel, with waste responsibilities being passed from generation to generation, each deciding the proper role and place for nuclear waste for the next generation, on the basis of what is best for their own generation.
"We can't be stewards for people living even 100 years from now," he says. A 35-year generational window provides a clear view of the future, he points out. On the basis of this view, Russell says he is content with on-site storage.
Fri recommends creation of a new sort of institution to oversee the future of high-level nuclear waste; not an operational entity, he says, but a board to oversee the development and management of a process to handle the waste forever.
"This waste is not like other wastes. You are not going to clean it up and watch it for a few years," Fri says. "Society will have to make decisions about how a future process works. It doesn't matter if the waste sits in a hole in the ground or is part of a new reprocessing system with fast-burner reactor technologies. All this will take time, and meanwhile we are stuck with a problem. This is going to be handed from one generation to the next."
On the other hand, Makhijani and Cochran see the need for a permanent repository in the future, but not in Yucca Mountain. Both oppose reprocessing and stress the importance of keeping plutonium in the spent fuel out of the hands of a terrorist or rogue nation.
THAT PLUTONIUM also worries Shrader-Frechette and Hirsch. "It is a myth to talk about permanent storage," Shrader-Frechette says. "The only reasonable thing is monitored, retrievable storage, and the waste site must be hardened to protect against terrorist attacks."
Speaking to the value of spent fuel, Hirsch asks, "You know who is going to want to use this waste?" The answer, he says, is "a terrorist."
Shrader-Frechette also argues that the waste is a transportation risk and should be kept where it was generated for equity reasons. "Those who benefited from nuclear-generated electricity should also be responsible for the waste product," she says.
"This is half the story, giving someone in the future a very dangerous material and then saying 'this will be of great value to you someday, so meanwhile you must secure it so it won't hurt you,' " Shrader-Frechette says. "I wonder what reaction you would get if you polled today's generation, asking if they would be willing to receive a gift from the past with a burden so great one might question the feasibility and wisdom of having it at all," she says.
If there is any agreement here, it is that the U.S. needs the 20% of its electricity that now comes from nuclear energy and that on-site waste storage is the only available technology for the near future.
For the long term and nuclear energy's role in a carbon-constrained future, there is no clear path ahead, and the direction is likely to be set by the balance of economics and technology as nuclear energy competes with solar, wind, and cleaner coal technologies. Despite 60 years of study and debate, the U.S. is far from a solution to address high-level nuclear waste.
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