Countdown to Zero Day: Stuxnet and the Launch of the World's First Digital Weapon (12 page)

THE THREE-HOUR DRIVE
from Tehran to Natanz dropped the inspectors at their destination midmorning on that February day. Along the
way, they passed the Hoz-e-Soltan Lake on their left, a salt lake that evaporated in the summer and was knee-deep with brackish water in the winter, and the city of Qom on their right, a center of Shi’a learning and one of the holiest cities of Islam.

Once they passed Qom, an endless vista of sand and highway greeted them for 60 miles until they reached the town of Kashan. Another twelve miles after that, in a wilderness composed of varying shades of brown and beige, a collection of buildings emerged on the horizon, as if sprung from the desert floor.

When they reached Natanz, Heinonen was startled to see that construction at the sprawling complex was much further along than he’d expected. In addition to the underground halls, a maze of buildings aboveground was already erected, including a cluster of five prefabricated structures with aluminum siding that fanned out from one another like the beams of a disjointed cross. A large electric substation had also been erected to power the buildings and the centrifuges. One of the five buildings turned out to be a pilot fuel-enrichment plant, a research facility where technicians could test new centrifuge models and cascades before installing them in the underground production halls. Once installed in the halls, the centrifuges would be expected to spin for years on end, so the pilot plant was crucial for verifying beforehand that the technology and enrichment process worked.

Although the underground halls were still a long way from being operational, technicians already had about 160 centrifuges spinning in the pilot plant, and components for hundreds of other centrifuges were waiting to be assembled there.
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The pilot plant was slated to begin operation in June, still four months away, but Iran expected to have 1,000 centrifuges installed in it by the end of the year, with the first batch of low-enriched uranium produced within six months after that.

As Aghazadeh led them around the plant, he took pains to insist that
no uranium hexafluoride had been introduced to Natanz yet, and no enrichment tests had been conducted using gas, either. Testing, he said, had only been done using computer simulations. It was an important distinction to make, since enriching uranium without notifying the IAEA would have violated Iran’s safeguards agreement. But Heinonen wasn’t buying the story. The idea that Iran had spent $300 million to construct a uranium enrichment plant without first testing cascades with actual gas to make sure the enrichment process worked stretched the boundaries of belief.

From the pilot plant, the inspectors were next taken to a showroom where the Iranians had carefully laid out, like a high-end science project, all of the individual components of an IR-1 centrifuge, as well as a pair of fully assembled ones. Aghazadeh told the inspectors that Iran had produced the IR-1s from a design of its own making. But when Heinonen moved in for a closer look, he noticed that they resembled an early-generation Urenco design that the consortium had made in Europe years earlier. He didn’t know yet that Iran had actually purchased the stolen design from A. Q. Khan, but he was already suspicious of the tales Aghazadeh was spinning.

After they finished examining the showroom, the inspectors were driven down the U-shaped tunnel that Corey Hinderstein had spotted on satellite images, to view the two cavernous halls buried seventy-five feet beneath the ground. Iran didn’t plan to begin filling the halls with centrifuges until 2005, but at 32,000 square meters each, they were expected to hold about 47,000 centrifuges when filled.
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For the time being, however, they were empty shells.

Throughout the visit, interactions between the inspectors and Iranian officials had been cordial. But things grew tense when the caravan returned to Tehran in the afternoon and Heinonen asked his hosts to show
him their secret cache of uranium. Aghazadeh was taken aback by the question and pleaded ignorance. Heinonen had come armed, however, with intelligence from Western government sources that in 1991 Iran had secretly imported uranium from China, including uranium hexafluoride.
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He brandished a letter from Chinese officials confirming the transaction. When the Iranians later produced the uranium, saying they had forgotten they had it, Heinonen and his colleagues noticed that the containers were lighter than expected and that some of the uranium hexafluoride gas seemed to be missing. The Iranians said it must have evaporated through leaks in the containers, but Heinonen suspected it had been used for secretly testing centrifuges.

That’s when Heinonen insisted on seeing the Kalaye Electric watch factory as well. At its press conference in August, the NCRI had identified Kala Electric, a slightly different spelling, as one of the front companies Iran had been using for its secret nuclear program. The NCRI hadn’t said what role the company played in the program, but shortly before the IAEA inspectors arrived in Iran to visit Natanz, the NCRI conveniently announced that the Kalaye facilities were used for researching and developing centrifuges. This, plus the undisclosed uranium, gave Heinonen the ammunition he needed to insist on a last-minute visit to the factory.

The Iranians reluctantly showed them the Kalaye office building, a mostly empty structure, but insisted they couldn’t find the keys to open the factory itself. The inspectors were scheduled to leave Iran the next day, so they extracted a promise to see the factory on their next visit. Unfortunately, by the time they returned to Iran more than a month later, the Iranians had had plenty of time to do spring-cleaning. The inspectors noticed obvious signs of freshly painted walls in one of the factory buildings, as well as doors that had been replaced and floor tiles that had been newly grouted. Suspicious that the Iranians were covering something up, the inspectors
asked to collect environmental samples from the building to test for traces of enriched uranium.
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Environmental sampling was something the IAEA had added to its repertoire after its failure to detect Iraq’s illicit nuclear program. Inspectors used special cotton squares and swabs to collect dust from walls and surfaces that could be tested to detect uranium particles as small as a picogram, determine the type of uranium that was present, and even gauge whether it had been enriched and to what level.
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But the Iranians refused to let them collect any samples.

Months later, when they were allowed to collect samples at the factory, as well as from the pilot enrichment plant at Natanz, they found low- and highly enriched uranium particles that were not on Iran’s list of declared materials.
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Confronted with evidence of this deception, officials finally admitted that they had enriched uranium gas at Kalaye, a violation of Iran’s safeguards agreement with the IAEA. But they said the gas was enriched only to test the centrifuges and was enriched only to 1.2 percent. This didn’t jibe with the particles the IAEA had collected, however, which ranged from 36 percent to 70 percent enriched.
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Uranium in its natural state contains less than 1 percent of U-235, the isotope needed for reactors and bombs. Most nuclear reactors need uranium enriched to just 3 to 5 percent. Highly enriched uranium is enriched to 20 percent or more. Although 20 percent enrichment can be used for crude nuclear devices, in addition to some types of nuclear reactors, weapons-grade uranium is enriched to 90 percent or above.

Iranian officials insisted the highly enriched particles must have come from residue left inside used centrifuges that Iran had purchased—an
admission that the centrifuge design wasn’t Iran’s own, as they had previously stated, and that some other nation was helping Iran build its program. Suddenly, concern over the nuclear program ratcheted up.

The environmental samples weren’t proof that Iran was working on a covert nuclear weapons program, but they were indications that inspectors had a lot of work ahead of them to try to uncover the scope of Iran’s nuclear program. They were also indications that nothing Iranian officials said could be trusted. It was the start of a long and exhausting dance that would occupy the IAEA the rest of the decade as inspectors tried to piece together the history of Iran’s nuclear ambitions and gauge its nuclear weapons capability.

Just as the IAEA was beginning this dance, the NCRI announced in May 2003 that it had evidence of additional secret nuclear sites in Iran, including one at a village called Lashkar Ab’ad. Iran admitted it had a pilot plant there for conducting laser enrichment experiments—another method for enriching uranium.
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And a couple of months later, the NCRI announced the existence of two more nuclear sites, including one in a warehouse district outside Tehran that was surrounded by auto junkyards to disguise it. The NCRI said it was a secret pilot enrichment plant that Iran had set up after the IAEA’s February visit to Natanz so that technicians could conduct enrichment experiments in secret, away from the prying eyes of inspectors.
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With so many public revelations in rapid succession, it was clear that someone was trying to keep the fire beneath Iranian officials stoked. But the revelations kept IAEA inspectors busy as well, since they now had to add more facilities to their list of sites to monitor. In addition to Bushehr and two reactor facilities already on the list, the IAEA added the pilot and
commercial enrichment plants at Natanz, the reactor being planned for Arak, and a uranium conversion plant at Esfahan, about a hundred miles southwest of Natanz, where Iran planned to convert uranium into gas to be enriched at Natanz.

WHILE QUESTIONS ABOUT
its nuclear program were being raised, Iran defiantly pressed forward with its uranium enrichment plans. In June, workers at Natanz began feeding the first batch of uranium hexafluoride gas into ten centrifuges at the pilot plant, setting off more alarms. Foreign ministers from the EU3—France, Germany, and the UK—urged Iran to suspend its enrichment activities until the IAEA could learn more about its nuclear program. A round of negotiations ensued and Iran agreed in October to suspend its enrichment activities temporarily. It also agreed to produce a detailed history of its nuclear program to remove “any ambiguities and doubts about the exclusively peaceful character” of it.
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Iran stuck to the latter agreement to a degree, but when officials delivered their detailed history to the IAEA, acknowledging that the centrifuge program had been in development on and off for eighteen years, they left a number of important details out.
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The IAEA only knew this because while the agency had been trying to extract information from Iranian officials, it had also begun learning more about the secret nuclear program from the CIA.

A few years earlier, the CIA had infiltrated the nuclear supply network of A. Q. Khan by securing the allegiances of a few of his key European suppliers and turning them into moles. From them, the CIA learned that Khan had sold the designs for Pakistan’s P-1 centrifuge—the design stolen from Urenco—to Iran and had also sold prototypes for its more advanced
P-2 centrifuge to Libya. If Khan sold the P-2 design to Libya, Heinonen reasoned, he must have given it to Iran as well. Iran hadn’t mentioned the advanced centrifuge in its detailed history, but if it did possess the centrifuges, then it was possible that Iran’s uranium enrichment program was much further along than Heinonen suspected. The IAEA pressed Iran to come clean about whether it was producing P-2 centrifuges, and officials admitted that they had indeed received a design for the P-2 centrifuge in 1996. Workers had tried to develop centrifuges from the design around 2002, officials said, but had abandoned the project shortly thereafter, after encountering problems making the centrifuge rotors. Iranian officials insisted to the IAEA that they hadn’t been trying to hide their work on the P-2s, but had simply planned to disclose it later.

Things grew worse over the next few months after questions arose about yet another secret facility in Iran, this one a building at the Physics Research Center in Tehran.
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By the time inspectors got access to the site to examine it, however, the building had been razed and the topsoil trucked away, thwarting efforts to collect environmental samples for testing.
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That April, Iran announced plans to begin conducting tests at Esfahan to convert milled uranium ore, or yellowcake, into uranium hexafluoride gas. The EU3 considered this a violation of Iran’s temporary suspension agreement, since converting ore to gas was a precursor to enriching the uranium, but decided not to press the issue, fearing that Iran would cancel the already delicate suspension agreement altogether.

Then that May, the IAEA was suddenly gifted with a large cache of documents, of mysterious provenance, that further intensified concerns about Iran’s nuclear program.

It began when Heinonen got a call from a woman with an American
accent who said her name was Jackie. He suspected she was from the CIA but didn’t ask. She knew details about his investigation into Iran’s nuclear program and said that she had information that would be of interest to him. Heinonen was wary of being manipulated by the CIA, but agreed to meet her at a Starbucks.
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When he arrived at the coffeehouse, a young Asian woman was waiting to speak with him. She told him she would arrange a meeting for him with two of the CIA’s moles who had been inside the Khan nuclear supply network and who could brief him about Khan’s dealings with Iran. She also said she had a stash of documents about Iran’s nuclear program that she wanted to show him. The documents came from a businessman in Tehran who had worked for the government in the steel and concrete industries—activity that took him to Natanz and Esfahan and put him in touch with the people behind Iran’s nuclear program. Somehow he had gained access to a large cache of highly sensitive documents about the nuclear program and had been passing them along to Germany’s intelligence agency, the BND. “Dolphin,” as the BND dubbed him, had planned to use the documents as a ticket to asylum in the West for him and his family. But before he could execute his plan, Iranian intelligence agents arrested him. His wife and children managed to flee across the border to Turkey, however, taking the documents with them.