Three and a half years after the Sept. 11, 2001, attacks, the government has failed to address the risk that a passenger plane flying at high speed could be deliberately crashed into a commercial nuclear plant, setting off fires and dispersing large amounts of radiation, a long-awaited report by the National Academy of Sciences has concluded.

Officials at the Nuclear Regulatory Commission have maintained that such an attack is improbable and that detailed analyses of the consequences of such attacks are unnecessary. Experts at the nation’s premier scientific body said those judgments are flawed.

“There are currently no requirements in place to defend against the kinds of larger-scale, pre-meditated, skillful attacks that were carried out on September 11, 2001,” a panel of scientists said, even as it agreed such an attack would be difficult to pull off.

Academy officials battled the government for months to make their declassified conclusions public — and the version released yesterday charged that federal secrecy edicts designed to keep information from terrorists were paradoxically hurting efforts to defend against such attacks.

Restrictions on sharing information imposed by the NRC had kept the industry from addressing vulnerabilities, the report said.

As a result, government labs and independent researchers have sometimes worked at cross-purposes, searched for solutions that others had already found and duplicated complex analyses.

NRC spokesman Scott Burnell said the agency “respectfully disagrees” that there are no provisions to deal with major attacks.

Security measures have been upgraded since 2001, and the agency continues to analyze risks, he said. But he emphasized that such attacks are improbable and that other agencies are guarding against them.

“We do believe that the possibility of a successful attack using commercial aircraft is very small,” he said. It is impractical to ask commercial plants to defend against such attacks, Burnell concluded. But he said plants are aware of the risk and are implementing measures to deal with worst-case scenarios.

As to the complaint of excessive secrecy, Burnell said the commission has to implement the law, which requires controls on information that could be misused. The debate is not over classified information but rather over sensitive data that ought not to be publicized.

In an earlier interview, E. William Colglazier, executive officer of the academy, said the nuclear agency’s guidelines for this classification are vague. Even when officials agreed that certain details in the report are not secret, he said, they had argued that chunks of non-secret information, when presented together, constituted “Safeguards Information.”

The report said government scientists and independent researchers had conducted analyses of threats without knowing that others were doing the same.

Burnell acknowledged that “the system was not perfect” but said that as more people receive security clearances such bottlenecks could be reduced. The commission has indicated it is seeking to increase access to information.

To the relief of the industry, the academy report disputed a characterization that the commission used in a letter to Congress on March 14. The letter implied that the academy was recommending moving spent nuclear fuel from large pools to dry storage casks. Industry believes that the pools are as safe as the casks and that moving the fuel is not worth the expense.

Louis J. Lanzerotti, chairman of the academy’s report, said that his panel had called for analyses of large attacks and that those results might prompt the commission to move fuel to dry storage at some plants.

Although dry storage has advantages, the risk of major attacks could be sufficiently addressed by changing how spent fuel is stored in pools and by installing water sprays to control fires, said the academy’s Kevin Crowley, the study coordinator.

Originally published by The Washington Post