UN Experts Say They Can't Be Fooled in Iran Probe
By Louis Charbonneau
VIENNA, Austria (Reuters) - U.N. experts say that if Iran has an atomic weapons program they will find evidence of it as they arrive Friday from Vienna for a month of intense inspections.
Technical experts from the Vienna-based International Atomic Energy Agency flew into Iran ahead of an Oct. 31 deadline to prove the country has no secret atomic bomb program. Washington alleges that it does while Tehran says it does not.
The agency has had success before. Before 1991, the IAEA discovered and dismantled Iraq's bomb program.
An A-bomb maker still needs 45 to 65 pounds of arms-grade uranium or plutonium to build a bomb. This leaves a highly detectable trail, says the IAEA, which says it can detect atomic particles down to a single picogram -- one trillionth of a gram.
"If you handle weapons-grade materials, trace amounts get out," said Therese Renis, a technical specialist at the IAEA.
She compared the agency's ability to find nuclear traces to finding one among thousands of marbles spread across a square mile in the center of the Austrian capital.
Some of the technology IAEA inspectors use to find sub-microscopic traces of fissile uranium and plutonium appears deceptively simple at first glance. The most important tool is a cotton swab used for environmental sampling.
Inspectors are especially interested in swiping areas around ventilation systems, light fixtures and the tops of shelves, said David Donohue, head of the IAEA's Clean Laboratory Unit.
"Wherever people don't usually dust," he explained.
CONTAMINATION EXPLANATION IN VOGUE
Such inspections have already yielded suspicious results in Iran -- traces of arms-grade highly-enriched uranium at two nuclear sites. This has fueled suspicions that Tehran has been secretly purifying uranium for use in a bomb, which Iran denies.
The Iranians say the uranium came from contaminated machinery purchased abroad. But this explanation has met with widespread skepticism.
IAEA experts say Iran is not the first country to claim that the discovery of arms-grade material is due to contamination.
"It's in vogue," Renis said about the contamination explanation. "It used to be: 'your results are bad'."
Asked how many contamination claims have been confirmed, Renis said: "More have been disproved than proved."
After arriving at the IAEA labs in Seibersdorf, Austria -- a half-hour from Vienna -- the samples on the swabs taken at nuclear facilities in Iran or elsewhere are analyzed.
Great care is taken to prevent contamination of the swabs before and after they have been used to swipe a location. Six identical swipes are taken at each site and each is double-bagged and sealed to prevent cross-contamination.
Of the six swipes, several are analyzed, several archived and several sent to some of the IAEA's network of 14 labs around the world to ensure consistency.
If IAEA chief Mohamed ElBaradei decides to inform the agency's governing board about a finding by his inspectors -- as happened with the discoveries in Iran -- the results have been checked so many times that they are virtually unassailable.
"We have to have a high degree of confidence in our data to go that far," said senior IAEA safeguards analyst, Diane Fischer. "We want strong, conclusive evidence." http://reuters.com/newsArticle.jhtml?type=worldNews&storyID=3555126