WASHINGTON—U.N. International Atomic Energy Agency inspectors were anxious to learn if the military-run physics research center on the edge of Tehran was part of the uranium enrichment program that Iran had admitted hiding for 18 years.
But wrecking crews got in first.
Even as the inspectors waited in late 2003 for permission to enter, the top-secret Lavizan-Shian Technical Research Center was bulldozed flat and the tons of rubble and earth trucked into the desert and scattered, obliterating evidence that the IAEA had hoped to gather.
Iran's failure since then to fully explain activities at the site and its obfuscation, conflicting answers and stonewalling on other aspects of the enrichment program are at the heart of the crisis over its nuclear program.
The IAEA has been trying to determine whether Iran is developing nuclear arms behind the facade of a civilian nuclear project. Iran claims it has no weapons program.
Only by reconstructing the complete history and extent of Iran's nuclear work can the IAEA determine the truth. So far, that's been impossible.
"Even after three years (of investigation), I am not yet in a position to make a judgment on the peaceful nature of the program," IAEA Director General Mohamed ElBaradei lamented earlier this month to Newsweek magazine.
The dispute became a full-blown crisis on Jan. 10 when Iran ended a 26-month freeze on work on uranium enrichment, a method that produces fuel for both civilian power plants and warheads, depending on the duration of the process.
Iran claims the right to enrichment for peaceful purposes as a signer of the Non-Proliferation Treaty, the key international safeguard against the spread of nuclear arms.
But the IAEA board of governors in September declared Tehran in breach of its treaty obligations to disclose all aspects of its program to the IAEA. This includes complete information on Iran's deals with the Pakistani-led smuggling ring that also supplied the know-how and technology to develop nuclear weapons to Libya.
The United States, Britain, France and Germany are pushing to have the IAEA board ask the U.N. Security Council to step up pressure on Iran to answer the IAEA's questions.
In October 2003, Iran gave the IAEA what it declared was a full accounting of its nuclear program. Agency experts quickly began finding holes.
Iran has filled some gaps and is promising to fill the rest. But in a Nov. 18 report to the IAEA board, ElBaradei complained that "there still remain issues to be resolved" and Iran's "full transparency is ... long overdue."
The agency's most pressing questions concern Iran's work on the equipment used to enrich uranium, whether it got blueprints for a Chinese nuclear weapon, and more about what was going on at the razed Lavizan-Shian research center.
Here's what Iran has done in each of these areas and why the IAEA is concerned:
CENTRIFUGES: These are devices that are linked together in the thousands to separate uranium 235, the isotope used to fuel power plants and weapons, from uranium hexafluoride gas.
Tehran asserts that it's working only on the P1, an older centrifuge whose design it admitted buying as part of a 1987 deal with the smuggling network led by A.Q. Khan, the father of Pakistan's nuclear arsenal.
But IAEA experts who studied materials and documents that the Khan ring supplied to Libya concluded that, like Libya, Iran also received the design of the P2, a device twice as efficient as the P1.
Confronted by the IAEA, Iran admitted omitting from its 2003 declaration a 1995 purchase of P2 blueprints from the Khan network.
Iranian officials insisted that they did nothing with the blueprints until they were given to an engineering firm for limited research in 2002.
When IAEA inspectors visited the firm, they discovered that it had fabricated a P2 component from a specialized metal, maraging steel. They later determined that the firm had ties to the Iranian military.
Iran has dragged its feet on providing additional data on its P2 work.
"We have a deep and wide body of intelligence that Iran has a parallel clandestine centrifuge program, but we have never been able to get coordinates," said a U.S. official, who requested anonymity because of the sensitivity of the issue. "We assume it is a P2 capacity they are focusing on."
Those suspicions grew after Iran told the IAEA that it broke the seals on a stock of maraging steel when it resumed enrichment work at Natanz, a key research facility, he said.
While the metal has limited applications in the P1 program centered at Natanz, "it is basically a necessity in the P2," said the U.S. official.
U.S. experts, he said, believe that Iranian officials may have resumed work at Natanz so they could use P1 machines to investigate and resolve technical hurdles in the suspected P2 program.
"It doesn't seem credible that they got P2 design information and it sat on a shelf," said Corey Hinderstein of the Institute for Science and International Security, a private research group that monitors the Iranian program.
Another unanswered question related to the P2 work "is the level of the involvement of military or military organs," she said.
OTHER KHAN RING DOCUMENTS: The IAEA has outstanding questions about the 1987 deal in which Iran admitted purchasing P1 blueprints and components and related documents from the Khan ring.
ElBaradei revealed in November that one document Iran provided contained specifications for casting and milling enriched uranium metal into hemispheres—which have no application in civilian power plants, but form the explosive core of nuclear warheads.
Iran said it didn't ask for the document and did nothing with it.
But an official close to the IAEA, who asked not to be identified further, said the issue is a serious one and agency investigators are interviewing former members of the Khan network to assess Iran's claim.
Another pressing question is whether Iran bought blueprints for a Chinese-designed nuclear warhead in 1987 from the Khan ring.
Documents provided to Iran by the Khan network were identical to papers that Khan sold to Libya, which received a Chinese nuclear warhead design.
"This is a fairly new concern that opens up a new avenue of investigation ... that Iran is blocking," said the U.S. official. "This to us is one of the key indicators of weapons intent by Iran."
WARHEAD RESEARCH: The IAEA opened an inquiry earlier this month into whether Iran has been secretly developing a nuclear warhead for its medium-range missiles.
The official close to the agency said that the Bush administration has turned over to the agency thousands of pages of computer simulations and studies that appeared to indicate that Iranian missile experts have been working on such a program.
The data came from a laptop computer obtained by U.S. intelligence officials in 2004 reportedly from a source in Iran, the official said.
Iranian officials deny that such materials exist.
THE BULLDOZED PLANT: The IAEA also is still investigating activities that took place at the Lavizan-Shian site.
Iran told the agency that research there involved the treatment of casualties of a nuclear attack and that the Tehran municipal government razed the facility after it prevailed over the military in an ownership dispute.
Environmental samples taken by IAEA inspectors when they were finally allowed into the site last summer found no traces of radioactivity.
Iran has been refusing to allow agency experts to interview senior officers who ran the center or to inspect equipment removed from it that had both civilian purposes and applications for centrifuge development.
"The IAEA has hard evidence of dual-use equipment ordered for Lavizan that almost certainly was used in a centrifuge research and development program," said the U.S. official.
(c) 2006, Knight Ridder/Tribune Information Services.
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