Thursday, October 8, 2009

Spent fuel could remain at VY for 100 years or more

By BOB AUDETTE

Editor’s Note: This is the second in a series of stories dealing with the issue of spent fuel stored at the nation’s nuclear power plants.

BRATTLEBORO -- With spent fuel piling up at commercial nuclear power plants around the country and no permanent disposal site on the horizon, many power plant operators are hoping the federal government might soon endorse the interim storage of the waste at one or two locations in the nation.

The Nuclear Energy Institute, an industry-funded organization that promotes nuclear power around the world, is suggesting just that.

"An interim facility wouldn’t have to be huge," said Thomas Kauffman, senior media relations manager for NEI. If you were to put the 60,000 tons of spent fuel currently being stored in dry casks into one location, he said, "They would fit onto an area of about a square half-mile."

No site has been identified yet for interim storage.

"The industry has had some dialogue with volunteer communities," said Kauffman.

Those communities include the sites of decommissioned power plants.

One benefit of having centralized interim storage would be the removal of spent fuel from the sites of decommissioned power plants. By removing the spent fuel, clean up at those sites could be completed.

There are 21 decommissioned nuclear reactors in the United States, said Neil Sheehan, a spokesman for the Nuclear Regulatory Commission.

"Some of the plants that were permanently shut down have been totally dismantled, as in the case of Maine Yankee and Connecticut Yankee," he said. "If you go to those sites today, all you will find still there from the nuclear operations are the dry cask storage facilities. Other decommissioned plants, like Millstone, are mothballed, awaiting the shutdown of the other units still operating at the site."
More important than finishing the decommissioning of the sites, said Kauffman, safety and security would be improved if all the dry casks from every power plant site, active and decommissioned, were moved to an interim storage facility.

While centralizing the waste makes good common sense, said Jim Riccio, Greenpeace’s nuclear policy analyst, there is the worry that transporting the spent fuel more times than is necessary would increase risks to the communities that it is passing through.

"This stuff is going to be at reactor sites for the foreseeable future," said Riccio. "We should be taking steps to improve the security of this waste."

There is really only one solution to the nation’s nuclear waste problem, said Riccio.

"Stop producing it," he said. "There is no solution that is going to last longer than it takes to keep it out of the biosphere."

Spent fuel is stored at nuclear power plants either in spent fuel pools or in dry casks. Forty-five power plant sites around the country have dry cask storage.

At the Vermont Yankee nuclear power plant in Vernon, there are now 2,819 spent fuel assemblies in its spent fuel pool, a 39-foot deep pool of water located in the reactor building.

Each of Yankee’s fuel assemblies is 6 feet square, approximately 12 feet long and weighs about 700 pounds. The reactor core holds 368 fuel assemblies, each of which remains in the reactor for 4 1/2 years before being moved to the spent fuel pool.

The capacity of the spent fuel pool is 3,355 assemblies and room must be maintained to keep space for the full-core offload of the reactor’s 368 assemblies.

Last year, 340 of the oldest fuel assemblies were moved from the spent fuel pool and placed into five dry casks, which were themselves placed on a concrete storage pad just outside the reactor building.

Each cask weighs about 100 tons and contains 68 fuel assemblies.

By 2012, another seven to eight canisters will need to be filled and if the plant is closed that year, 55 to 60 dry casks will be needed.

If Vermont Yankee receives approval to continue operation for 20 years past its original license expiration date of 2012, five to six dry casks will need to be loaded every five to seven years to maintain full-core offload.

"Dry cask storage is proven," said Kauffman. "It’s safe. These things are designed to take anything that the plant can take," he said, including floods, fires, hurricanes, high and low temperatures and even impacts from aircraft. "They’re very tough."

Even if the storage pad at Vermont Yankee, which is located at an elevation of 254 feet above sea level, is flooded, he said, "The casks aren’t going anywhere. They wouldn’t be approved if they couldn’t handle that."

The storage pad is 1 1/2 feet higher than the location’s 500-year-flood level.

If storage outlasts the life of the casks, about 100 years, the spent fuel can be moved into new casks, he said.

"Because these are transferable, dry cask storage can last indefinitely," said Kauffman.

Even if Yucca Mountain or some other permanent site opens, it will take 100 years or more to move the spent fuel, meaning the waste at Vermont Yankee will probably be there for a long, long time.

Dry cask storage is also costly for electricity consumers, according to a document produced by Vermont Yankee.

"Each year of delay in the federal program for removing used nuclear fuel from reactor sites will add an estimated $1 billion in temporary storage costs," according to the document.

"We will need a federal repository at a minimum for the spent fuel in existence," said Ed Lyman, senior staff scientist for the United States branch of the Union of Concerned Scientists. "There’s really no alternative at this point. The one course of action that is not reasonable is to simply do nothing and proceed with building a large number of building new nuclear power plants."

Speaking for himself and not the Union of Concerned Scientists, Lyman said there is one option no one is talking about.

"States that want nuclear power plants should take more responsibility for final disposal of the spent fuel," he said.

On Thursday: Is the reprocessing of spent nuclear fuel the answer to the nation’s spent fuel woes?

Bob Audette can be reached at raudette@reformer.com, or at 802-254-2311, ext. 273.

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