Fukushima Disaster Deepens U.S. Turmoil Over Nuclear Waste Storage

New York Times Energy & Environment: Fukushima Disaster Deepens U.S. Turmoil Over Nuclear Waste Storage
Japan's nuclear disaster and the abandoned Yucca Mountain repository are combining to create a more complex puzzle for U.S. policymakers wrestling with the future of nuclear power in the United States.

On Friday, a Blue Ribbon Commission (BRC) of experts appointed by the Obama administration presented subcommittee reports calling for the "expedited" creation of one or more consolidated interim sites for storing spent fuel from commercial U.S. reactors. More than 70,000 tons of spent fuel with varying levels of remaining radioactivity are currently in "wet" or "dry" storage at the reactor sites, with nowhere else to go.

The subcommittee also recommended that the United States develop one or more permanent underground repositories for spent fuel in place of the proposed Yucca Mountain repository that has been shelved by the Obama administration. Both interim and permanent sites should only be located where local communities welcome them, and not imposed on a location, as Yucca Mountain was in Nevada, commissioners said. A new federal agency should be created to manage both interim and permanent site development, commissioners said.

A consolidated interim storage facility could take 20 years to locate, fund, license and build, according to the Government Accountability Office. A future permanent repository is even further in the future, the GAO said.

That leaves spent fuel storage at reactor sites as the only current option, if Yucca Mountain remains off the table. This could be the preferable path, according to Energy Secretary Steven Chu and members of a Massachusetts Institute of Technology study panel led by BRC member Ernest Moniz. Under this scenario, a decade or two of directed research on new reactor and fuel designs could lead to more efficient fuel cycles that would reduce the ultimate amount of spent fuel requiring storage.

Commission member Richard Meserve, a former Nuclear Regulatory Commission chairman, noted Friday that spent fuel may turn out to be either a waste or a resource, if safe and effective reprocessing strategies emerge. Interim storage "helps preserve the option of going in either direction depending on what we learn."

Republicans see a political favor to Reid

That possibility has not quieted Republican critics who say the decision to shelve the Yucca Mountain project was a purely political favor to Senate Majority Leader Harry Reid (D-Nev.). Revisiting the administration decision was not placed on the BRC's agenda.

The NRC has concluded that spent fuel is safe either stored "wet" in cooling pools or "dry" inside steel containers encased in concrete or steel casks. Fuel assemblies must be stored first in pools for up to five years until they are cool enough to be kept in passive dry cask storage.

A BRC subcommittee concluded: "There do not appear to be unmanageable safety or security risks associated with current methods of storage at existing sites. However, rigorous efforts will be needed to ensure this continues to be the case."

But the catastrophe at the Fukushima Daiichi nuclear complex in Japan has seeded doubts about the safety of on-site spent fuel storage, said commission Co-chairman Lee Hamilton, a former Indiana congressman and co-chairman of the 9/11 Commission. "The American people are deeply concerned about the safety of nuclear plant operations in this country. ... I don't think you have forever to answer that question," he told Lawrence Kokajko, acting deputy director of the NRC Office of Nuclear Material Safety and Safeguards, who represented the NRC at the commission session Friday.

Lessons of Fukushima remain unknown

More than two months after the start of the Fukushima crisis, critical details of what happened to the spent fuel held in elevated water pools in reactor buildings remain a mystery to U.S. regulators and the Blue Ribbon Commission members. Technicians had to wait several years after the 1979 nuclear accident at Three Mile Island before it was safe enough to directly assess the damage to the reactor. Crews at the Fukushima plant are in a daily struggle to control damaged reactors, and there is no guarantee that the accident details will become clear by the time the commission is planning to publish its draft final report, in July.

One such detail surrounds the spent fuel pool at reactor 4. At the peak of the crisis on March 16, Nuclear Regulatory Commission Chairman Gregory Jaczko told Congress that the unit's cooling water might be gone or nearly gone, threatening a fuel fire and major radioactivity release. Based on that threat, he recommended that U.S. citizens within 50 miles of the plant evacuate. Japanese officials challenged the report.

Jennifer Uhle, deputy director of NRC's Office of Nuclear Regulatory Research, told the BRC there were differing understandings of what had happened. Japanese authorities have concluded that the fuel was not exposed and that any damage in the pool was due to mechanical causes, she said.

"We don't really have the final answer," she said.

But the BRC staff reported this month that "recent video taken inside the Unit 4 pool shows that the fuel is in intact and largely or completely undamaged condition."

If one or more centralized sites were created for dry cask storage, the first priority should be moving the spent fuel from nine decommissioned nuclear plants, so that the sites can be reclaimed for other uses, BRC members said.

A follow-up issue for the BRC is whether the transfer of fuel from wet to dry storage should be accelerated, which could create a larger volume of dry casks for central storage. An interim storage facility could be located away from earthquake zones or flood-prone areas, possibly reducing the risk of radiation release from a severe natural disaster. The dry cask storage unit at Fukushima, which was located farther from the ocean than the reactors, escaped damage and has not released radiation, according to the U.S. experts.

'Not a complicated problem'?

Commission member Allison Macfarlane, a George Mason University professor, criticized utilities' practice of packing spent fuel assemblies more densely inside the fuel pools, which can increase the risk of radioactive releases from a fuel fire if cooling water is lost. "Why not get ahead of the curve and go back to a low-density rack?" she asked Kokajko.

"That certainly comes into consideration," he said.

"This is not a complicated problem. The only sticking point is the price tag," she responded.

The GAO reported last year that dry cask storage costs about $30 million to $60 million per reactor, with expenses increasing as more fuel is shifted from pools to casks. Some reactor owners employ dry casks to relieve crowding in their fuel pools. Others have not shifted any fuel to the dry option.

In another two decades, many of the first U.S. commercial reactors will be coming to the end of an extended 60-year license term. It far from settled whether they could qualify for a new relicensing for another 20 years, or whether their owners would choose that course, experts say. That could mean that a growing line of reactors will be headed for decommissioning and more reactor sites will be closed with only their legacy of spent fuel containers, expanding the case for centralized storage, Meserve said.

The NRC's Kokajko added an ironic historical footnote to the commission's Friday meeting with an observation about the General Electric Mark I reactors at Fukushima, whose spent fuel pools are located at the top of the reactor building, exposed to the hydrogen explosions that blasted the units. The pools are located at ground level in other reactor designs.

The Mark I pools weren't meant for long-term storage, he said. They were positioned high up to make it easier to move spent fuel from the reactor to the cooling pool and then out, "so the government could take it."