Spent Nuclear Fuel in U.S. Reactor Pools Vulnerable to Attack

By J.R. Pegg

WASHINGTON, DC, April 8, 2005 (ENS) – Spent nuclear fuel stored in pools of water at reactors across the nation may be at risk from terrorist attacks, says a new report from a committee of the National Academy of Sciences.

An attack that partially or completely drained a plant’s spent fuel pool could cause a high temperature fire and release “large quantities of radioactive material into the environment,” the committee concludes in its report, released Wednesday.

The committee called on the federal government to evaluate the vulnerability of each of the nation’s 103 nuclear reactors in order to reduce the potential consequences of a successful attack.


When spent fuel is removed from a nuclear reactor, it is placed in a special pool of water contained in a steel-lined, concrete basin. (Photo courtesy DOE)
Congress requested the study following conflicting claims in the media about the safety and security of spent fuel in storage at commercial nuclear power plants, including the risks that spent fuel might be used to construct a radiological dispersal device, or "dirty bomb."

The committee concluded the likelihood that terrorists could steal enough spent nuclear fuel from a power plant for use in a dirty bomb is small, given existing security measures. Still, it recommended that the Nuclear Regulatory Commission (NRC) should review and upgrade where necessary its security requirements for protecting those spent fuel rods not contained in fuel assemblies from theft by knowledgeable insiders.

The report was completed last summer but was not released to the public because of concern some of the information could expose the vulnerability of specific plants.

The NRC forged an agreement with the National Academies to release the unclassified version of the report that does not contain information on which plants are most at risk from an attack.

"We believe this report fulfills our responsibility to inform the public and elected officials on a critical national security issue," said Bruce Alberts, president of the National Academy of Sciences. "It also satisfies a second, equally important imperative: to ensure that this report contains no information that might inadvertently aid terrorists. We appreciate the Nuclear Regulatory Commission's assistance in confirming that."

Storing spent nuclear fuel is a major headache for plant operators - it must must be cooled in large pools of circulating water for five years after it is removed from a reactor.

The fuel can eventually be extracted and stored in heavy casks, but the process is expensive and operators have increasingly kept fuel in pools rather than in dry casks.


Dry cask storage of spent nuclear fuel (Photo courtesy DOE)
The committee said dry cask storage is ultimately preferable to pools because “is a passive system that relies on air circulation for cooling” and it also divides the total inventory of spent fuel into “individual, robust containers.”

To reduce the vulnerability of spent fuel pools, the committee recommended “reconfiguring the position of fuel assemblies in the pools to more evenly distribute decay-heat loads.”

That could be done at “all plants with minimal cost and time, and with little exposure of workers to radiation,” the committee said.

The panel also recommended plants implement water-spray systems to cool the fuel that could continue to operate even after the pool or the building that contains the pool is damaged.

Such systems may not be needed at plants where spent fuel pools are located below ground level or are otherwise protected from external line-of-sight attacks, the committee said.

Officials from the nuclear industry and the Nuclear Regulatory Commission said the study overstates the risk of an attack on spent fuel pools and they insist spent fuel pools are as safe as dry casks.

In a letter to Congress last month regarding the classified report, NRC Chairman Nils Diaz said “spent fuel is better protected than ever.”

“The results of security assessments completed to date clearly show that storage of spent fuel in both spent fuel pools and in dry storage casks provides reasonable assurance that public health and safety, the environment and the common defense and security will be adequately protected,” Diaz wrote.

Diaz told Congress the NRC has stepped up security assessments at nuclear reactors in the wake of the terrorist attacks of September 11, 2001 and will continue to review security at each plant “at least once every three years.”

Marvin Fertel, chief nuclear officer of the Nuclear Energy Institute, an industry trade group, said the industry has spent more than $1 billion in security improvements since 2001 “including used fuel storage facilities, to make them more secure than ever.”

The study and the NRC’s response “further validate what is already widely acknowledged by independent experts — namely that nuclear power plants have long been the best protected facilities in our nation’s industrial infrastructure,” Fertel said.

Committee Chair Louis Lanzerotti, distinguished research professor at the New Jersey Institute of Technology, defended the panel’s findings as “a very sound, evidence-based analysis.”

"We received input both from scientific professionals and the public,” he said. “Our findings were unanimous.”


Dr. Louis Lanzerotti is a distinguished research professor at the New Jersey Institute of Technology and a consultant to Bell Laboratories and Lucent Technologies. (Photo courtesy NAS)
The committee’s conclusions are based on a detailed review of security analyses performed by the NRC, the U.S. Department of Homeland Security, the nuclear power industry, and independent experts – and noted the security improvements the industry has instituted since 2001.

“On several important questions, however, it was unable to obtain enough information from the U.S. NRC to assess their effectiveness,” said the committee, which called for an assessment to be carried out by an organization “independent of the U.S. NRC and the nuclear industry.”

The report comes amid growing concern about the federal government’s plan for safeguarding its nuclear waste in a national geologic repository in Yucca Mountain, Nevada – a plan that has been embroiled in controversy and litigation.

That project, originally planned for completion in 2010, will not be ready until 2017 at the earliest, a U.S. Department of Energy (DOE) official said last month.

Safety of the Yucca Mountain site appears in even greater jeopardy in light of the announcement by Energy Secretary Samuel Bodman March 16 that documents and models about water infiltration at the repository have been falsified.

In the meantime, the problem of storing nuclear waste is growing in scope and expense, and power plants are left with little option but to store additional waste onsite.

As of 2003, nuclear reactors in the United States had generated some 54,000 tons of spent nuclear fuel and by the year 2035, the United States will have produced more than twice that amount.

Several court cases have ruled that the federal government is liable for the costs of storing the nuclear waste until the Yucca Mountain site is ready. The industry says that total bill could be some $56 billion.