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AFTER KILLING THE PROJECT TO ESTABLISH A nuclear waste repository at Yucca Mountain, Nevada, last year, President Barack Obama set up a commission to chart a new course for U.S. nuclear waste policy. The group, which is set to deliver its interim fi ndings at the end of this month, is expected to say that the answers to America’s nuclear waste conundrum are technically feasible. The problem, however, is that those solutions are likely to be, in political terms, radioactive.

The Blue Ribbon Commission on Amer- ica’s Nuclear Future confronts a challenge that has stymied Washington for 40 years: the nation’s relentless production of nuclear waste. In recent decades, U.S. reactors have created more than 2000 metric tons of highly radioactive spent fuel each year. Codifi ed in law in 1987, the Yucca plan meant the spent fuel, held in bundles of 4-meter-long zirco- nium alloy tubes, would be cooled for up to a decade in storage pools at U.S. reactors.

Then it would be shipped to Yucca Moun- tain, transferred into steel cylinders, and fur- ther cooled by fans for 50 years. When the facility contained 70,000 tons of waste, it would be closed up.

In the past 24 years, the Department of Energy (DOE) has built an 8-kilometer-long tunnel at Yucca and has conducted experi- ments to ensure that the reposi- tory could hold the waste for up to 1 million years without releasing dangerous amounts of radiation. But although the government has spent roughly $10 billion on the project, lawsuits, red tape, and political opposition have prevented DOE from disposing of a single ton of commercial fuel. About 65,000 tons of spent nuclear fuel are piled up at U.S. reactors in cooling pools and in steel-and-concrete casks stored out- doors. Some experts believe the pools rep- resent unacceptable safety or environmental

risks in the case of natural calam- ity or terrorist attack. But moving cooled-down fuel from U.S. pools into casks, which are considered safer, would cost utilities billions of dollars.

To alleviate this pressure on reactor sites and buy the govern- ment time to establish a perma- nent repository, the commission will likely call for an impor- tant new step: interim storage of the fuel in one or several central locations. After cooling in pools for a decade, fuel would be trans- ferred to such a facility to be stored in outdoor steel-and-concrete casks for “multiple decades up to 100 years or possibly more.” Over that period, the commission envi- sions, expanded federal research into fuel recycling or other tech- nologies might reduce the amount

of fuel requiring disposal. Meanwhile, fed- eral offi cials would have a second chance to establish a permanent U.S. geologic reposi- tory—this time, perhaps, in a fashion less acrimonious than the Yucca effort.

Buying time “Consolidated interim storage preserves options while other aspects of an integrated waste management strategy can be devel- oped,” says one of three commission sub- committee reports released in June. Later this month, an interim report from the full commission is expected; given the hundreds of hours of public testimony and published documents cited in the lengthy subcommit- tee reports, experts expect the fi nal version, scheduled to be released in January 2012, to offer substantially the same conclusions.

In addition to paving the political and logistical route to disposal, cen- tral, interim storage sites could make the repository easier to design and build. Building the Yucca repository required a num- ber of engineering tradeoffs, explains physicist Charles Fors-

berg of the Massachusetts Institute of Tech- nology (MIT) in Cambridge, and the site’s “awkward” design was a stumbling block to getting it licensed.

One reason was that Yucca Mountain had to cool waste before permanently storing it. Spent fuel straight from the reactor can

Online sciencemag.org

Podcast interview with author

Eli Kintisch.

Hot stuff. Spent fuel being lowered

into a storage cask at a commercial

nuclear reactor in Virginia.

NEWSFOCUS

Waste Panel Expected To Back Interim Storage A blue-ribbon commission signals that spent nuclear fuel should cool

above ground while the United States fi gures out long-term disposal

Published by AAAS

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www.sciencemag.org SCIENCE VOL 333 8 JULY 2011 149

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Spent fuel in metric tons

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States with <1 ton of spent fuel

States with no spent fuel

Spent nuclear fuel is piling up at 77 sites (small dots) in 35 states.

Where the Waste Is

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quickly reach 1500ºC, hot enough

to destroy the tubes that hold it.

Cooling for about a decade in stor-

age pools dissipates most of the

heat from the shortest-lived iso-

topes. But after being bundled

together and entombed in the

mountain for centuries, it might

still gradually create enough

heat to aid corrosion of the

tubes, create dangerous steam

within the tunnels, or even, over

time, alter the geology of the

site. First cooling the waste for

at least 5 decades at interim stor-

age sites could eliminate the need

for fans at a permanent reposi-

tory, says Forsberg, co-author of

several infl uential MIT reports on

nuclear waste. The interior of the

long-term repository—compared

with Yucca Mountain—would also

require less ventilation and less

access by remote devices to han-

dle the fuel after emplacement,

and it could be more easily sealed with an

appropriate fi ll.

In any case, experts agree, some new plan

for waste storage is essential. Waste currently

stored in pools and casks at U.S. sites does

not pose “unmanageable … safety or security

risks,” says a subcommittee report. But every

ton that stays at reactor sites makes those

risks slightly greater. Fuel in U.S. spent fuel

pools is packed four times as densely as it was

25 years ago, raising concerns about the risk

of explosions or meltdown if the pools were

to empty in an accident. The tsunami that dev-

astated the Fukushima nuclear plant in Japan

in March may have resulted in a loss of water

in one of its ponds (Science, 1 April, p. 24).

A draft commission report says the issue of

the safety of keeping fuel densely packed in

pools should be “reexamined,” although “it is

still too early to draw defi nitive conclusions”

from the Fukushima accident. It calls for an

expert panel at the National Academies to

tackle the subject.

If an interim storage site could

get licensed—a big if, given polit-

ical sensibilities—it might save

money for utilities and the govern-

ment, which is currently paying

hundreds of millions of dollars in

legal claims to utilities for the waste.

Nine decommissioned reactor sites

in the United States currently house

nuclear fuel in aboveground casks.

Centralized storage could save utili-

ties billions in security costs and by

freeing the land for other uses.

As for long-term disposal, commis-

sioners say the government should “expe-

ditiously” move to set up a geologic

repository—they were told not to specify

where. “There is no ethical basis for abroga-

tion of responsibility” for securing nuclear

waste “to future generations,” a subcom-

mittee report says. To avoid repeating the

Yucca Mountain experience, which was

plagued by opposition from the state of

Nevada (see p. 150), the process of choos-

ing a site should include “consultation,

transparency, accountability, and scientifi c

and technical credibility,” a draft report

says. Commissioners are also likely to call

for the project to be managed by a new,

independent entity.

The commission is also likely to recom-

mend expanding research into technolo-

gies such as reprocessing, in which nuclear

waste is converted back into nuclear fuel,

and into advanced or more effi cient reac-

tors that might produce less waste. Nuclear

power will never be completely clean, how-

ever. “No currently available or reasonably

foreseeable reactor and fuel-cycle technolo-

gies … have the potential to fundamentally

alter the waste management challenge,” the

research subcommittee draft says.

The road ahead

Forecasting what the Blue Ribbon Com-

mission will recommend is one thing; pre-

dicting what the Obama Administration and

its successors will actually do with them is

much harder. Several environmental and

antinuclear groups have already spoken out

against creating new storage sites for waste,

and a commission subcommittee admits

in a report that it’s a “contentious issue.”

Commissioners hope the track record of the

57 licensed fuel storage facilities—most at

U.S. reactor sites—will alleviate some fears,

and that an open site-selection process cou-

pled with “incentives” like training and jobs

for local communities and utilities will ulti-

mately carry the day.

But even simply getting money for more

federal research into nuclear power could be a

challenge. As the budget process in Washing-

ton grows ever more contentious, lobbyists

and activists alike are increasingly skeptical

that substantial increases can happen soon. “I

don’t think the budgets are going to expand

beyond what they are now,” says physicist

Thomas Cochran of the Natural Resources

Defense Council in Washington, D.C.

–ELI KINTISCH

Fuel Stored in Dry Casks

Fuel Stored in Cooling Pools

2010

20,000

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2015 2020 2025 2030 2035 2040 2045 2050 2055 2060

Plain spent. Assuming no new plants, used fuel stores will

more than double by 2050.

NUCLEAR WASTE NEWSFOCUS

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