Life after Yucca Mountain
Geologist Allison MacFarlane on the future of nuclear waste–and what it means for nuclear power.
In 1982, the U.S. government formally accepted the dirty job of finding a place to dispose of highly radioactive nuclear waste, including spent reactor fuel, which will remain radioactive for hundreds of thousands of years. Five years later, Congress directed the U.S. Department of Energy to begin seriously investigating a single site–Yucca Mountain, NV–as a permanent geological repository. But earlier this year, with 60,000 metric tons of spent fuel clogging storage facilities at power plants, the Obama administration announced that it would cut Yucca’s funding and seek alternatives.
Allison Macfarlane, a geologist at George Mason University and the editor of Uncertainty Underground: Yucca Mountain and the Nation’s High-Level Nuclear Waste, is a leading technical expert on nuclear-waste disposal who recently sat on a National Research Council committee evaluating the Department of Energy’s nuclear-power R&D programs. She spoke with David Talbot, Technology Review’s chief correspondent, about the future of nuclear waste–and what it means for the future of nuclear power.
TR: You are known as a Yucca critic. Does this mean you oppose nuclear power?
Allison Macfarlane: Not at all. From the point of view of climate change, we absolutely, definitely need nuclear power.
TR: Only last year, the Bush administration filed the necessary application with the Nuclear Regulatory Commission to construct Yucca. Now Obama’s energy secretary, Steven Chu, says Yucca is “off the table.” Is it really unsuitable?
AM: Yes. The area is seismically and volcanically active. More significantly, the repository would have an oxidizing environment–meaning materials there would be exposed to free oxygen in the air. Neither spent nuclear fuel nor canister materials are stable in such an environment in the presence of water. The United States is the only country that is considering a repository in an oxidizing environment.
TR: Then why was Yucca Mountain the government’s choice for 22 years?
AM: Mostly political reasons. Originally three sites were considered: Yucca, and ones in Texas and Washington State. Congress balked at the price tag of characterizing three sites at once. In the ensuing fight to keep the waste program alive, Nevada was the politically weakest of the three and lost the battle.
TR: Politics helped end the matter, too. Nevada’s senior senator, Harry Reid, is now Senate majority leader and has long opposed Yucca.
AM: Maybe–but the technical objections are serious and real.
TR: Will the administration’s decision stall any renaissance in nuclear energy?
AM: No. There’s no historical example showing that a lack of a plan for nuclear waste will halt the progress of nuclear energy.
TR: What now?
AM: Within the next five years, almost every nuclear power plant will have dry-cask storage: the waste will be moved from storage pools to outdoor concrete-and-steel casks inside plant security perimeters. As an interim solution, that’s quite safe. But eventually the casks will corrode and break down and release radioactive material into the environment, though it will probably take hundreds of years. That’s why we need geological storage.
TR: What’s the right geology?
AM: Waste should be stored in a reducing environment [one not exposed to free oxygen], and this usually means underneath the water table, though salt formations can be reducing even if they are not below the water table. The Swedes and Finns are planning to put their waste inside granite and metamorphic rock, and the storage casks will be below the water table. And that’s all okay. Spent fuel–which is just uranium dioxide, fission products, and actinides [radioactive elements, including plutonium]–is relatively stable under such conditions. With no free oxygen, it just sits there.
TR: Will we still need such storage even if future reactors burn more of the plutonium–or even if future generations decide to reprocess some of the old spent fuel to recover plutonium?
AM: Yes. The French reprocess spent fuel, but they still need a repository. They are doing research on a site at Bure, in northeast France. It has a kind of sedimentary rock that’s relatively fine grained, and it’s a reducing environment.
TR: So where are the suitable storage locations in the United States?
AM: There are lots, all over the country.
TR: Then it should be easy to name two or three.
AM: I haven’t studied anything in detail, and I don’t want to get anybody upset. But we have a huge country, and there are many locations. One thought, though, is that sites could be in locations where people already have a comfort level with nuclear power, which is how the Swedes and Finns have been successful.
TR: It took 22 years and $8 billion to get nowhere on Yucca. Politics aside, how long will it take, and how much will it cost, to get U.S. storage sites opened?
AM: We didn’t get nowhere. We learned quite a bit. We should set aside something on the order of a few decades to get this right. It will cost billions, but that’s part of the price of nuclear power.
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