Addressing the Unthinkable, U.S. Revives Study of Fallout

Friday, March 19, 2004
By William J. Broad

New York Times Writer

Federal experts say complex threat scenarios (for instance, an American warhead being stolen and detonated in an American city) mean that many types of intelligence might be needed for successful identification. Over all, it is unclear how much money the government is spending on the effort. Private experts offered suggestions for improvement. Dr. Happer of Princeton, who heads a university board that helps oversee campus research, said the program might be cooperating too little with nuclear allies. "It's to our advantage," he said, "for all of us to share."

NYT
To cope with the possibility that terrorists might someday detonate a nuclear bomb on American soil, the federal government is reviving a scientific art that was lost after the cold war: fallout analysis.

The goal, officials and weapons experts both inside and outside the government say, is to figure out quickly who exploded such a bomb and where the nuclear material came from. That would clarify the options for striking back. Officials also hope that if terrorists know a bomb can be traced, they will be less likely to try to use one.

In a secretive effort that began five years ago but whose outlines are just now becoming known, the government's network of weapons laboratories is hiring new experts, calling in old-timers, dusting off data and holding drills to sharpen its ability to do what is euphemistically known as nuclear attribution or post-event forensics.

It is also building robots that would go into an affected area and take radioactive samples, as well as field stations that would dilute dangerous material for safe shipment to national laboratories.

"Certainly, there's a frightening aspect in all of this," said Charles B. Richardson, the project leader for nuclear identification research at the Sandia National Laboratories in Albuquerque. "But we're putting all these things together with the hope that they'll never have to be used."

Most experts say the risk of a terrorist nuclear attack is low but no longer unthinkable, given the spread of material and know-how around the globe.

Dr. Jay C. Davis, a nuclear scientist who in 1999 helped found the Pentagon's part of the governmentwide effort, said the precautions would "pay huge dividends after the event, both in terms of the ability to identify the bad actor and in terms of establishing public trust."

In a nuclear crisis, Dr. Davis added, the identification effort would be vital in "dealing with the desire for instant gratification through vengeance."

Vice President Dick Cheney was briefed on the program last fall, Dr. Davis said. The National Security Council coordinates the work among a dozen or so federal agencies.

The basic science relies on faint clues — tiny bits of radioactive fallout, often invisible to the eye, that under intense scrutiny can reveal distinctive signatures. Such wisps of evidence can help identify an exploded bomb's type and characteristics, including its country of origin.

Solving the nuclear whodunit could take much more information, including hard-won law enforcement clues and good intelligence on foreign nuclear arms and terrorist groups. For that reason, several federal agencies are involved in the program, among them the Department of Homeland Security and the Federal Bureau of Investigation.

The program addresses true nuclear weapons as well as so-called dirty bombs, ordinary explosives that spew radioactive debris.

"It's a very hard job," said William Happer, a physicist at Princeton who led a panel that evaluated the identification work.

Mr. Happer said he was worried that a rush for retribution after a nuclear attack might cut short the time needed for careful analysis. "If we lose a city," he said, "we might not wait around that long."

The effort to fingerprint domestic nuclear blasts is part of a larger federal project to strengthen the nation's overall defenses against unconventional terrorist threats. Mostly, the goal is prevention. For instance, the government recently sent teams of scientists with hidden radiation detectors to check major American cities for signs that terrorists might be preparing to detonate radiological bombs.

In contrast, the identification program seeks to increase the government's knowledge and options should prevention fail. "We're trying to resurrect some of our capability," said Reid Worlton, a retired nuclear scientist from the Los Alamos weapons laboratory in New Mexico who has been called in to aid the fallout endeavor. "It sort of died. They're not doing radiochemistry on nuclear tests anymore, so it's hard to keep these people around."

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Dan