WASHINGTON _ Iran has crossed a new nuclear threshold, but it's one the Obama administration isn't worried about.
On Saturday, technicians began loading low-enriched uranium fuel supplied by Russia into Iran's first civilian nuclear reactor, and if all goes smoothly, the Bushehr plant could start producing electricity under United Nations monitoring late this year or early next.
"The International Atomic Energy Agency regularly inspects the Bushehr Nuclear Power Plant in Iran. Iran began moving fuel assemblies to the plant's reactor compartment on 21 August 2010," Ayhan Evrensel, a press officer for the International Atomic Energy Agency, said in a statement Saturday. "The agency is taking the appropriate verification measures in line with its established safeguards procedures."
Bushehr embodies what the administration and many experts consider an ideal solution to the Iranian nuclear dispute: The Islamic republic benefits from the peaceful nuclear energy to which it's entitled by international law, but the fuel comes from elsewhere, negating Iran's need to make its own via enrichment, a process that also can produce highly enriched uranium for nuclear bombs.
Moreover, under a 2007 accord negotiated by the Bush administration, the spent fuel rods will go back to Russia after they've cooled to prevent Iran from harvesting them for plutonium, the other essential component of nuclear weapons.
"Because the Bush administration did such a good job of neutralizing the Bushehr reactor, we don't view it as a proliferation threat," said a White House official, who requested anonymity to discuss the issue freely.
Some experts, however, disagree. They warn that Iran could still use Bushehr to enhance its uranium enrichment program — located some 300 miles away at Natanz — that the U.N. Security Council is demanding be halted amid charges that it is part of a secret nuclear arms development project. Iran denies the allegation.
"I'm not arguing that it is obvious they will do this," said Henry Sokolski, a former Pentagon official who served on the congressionally mandated Commission on the Prevention of Weapons of Mass Destruction Proliferation and Terrorism. "But it increases the uncertainty budget. It doesn't simplify things to have this reactor operating."
At a minimum, the facility can serve as "an enormous cover" through which Iran can bring in weapons-related technology and experts prohibited by U.N. sanctions, said Sokolski, the director of the Proliferation Policy Education Center.
Critics of President Barack Obama have seized on the issue to launch fresh attacks on the administration's reliance on tougher international sanctions to compel Iran to suspend its uranium enrichment program and open negotiations.
John Bolton, who served as U.S. ambassador to the U.N. in the Bush administration, went so far as to warn Israel on Aug. 17 that it had only days left to bomb Bushehr because doing so after the reactor is fueled would spread radioactive contamination across the region.
"One doesn't have to take a John Bolton position or the official U.S. government position," said Simon Henderson of the Washington Institute for Near East Policy. "There are enough uncertainties . . . for us to look at the events that begin this weekend with some concern."
The fuel-loading ceremony set for Saturday has been decades in coming.
A German firm began building two 1,000-megawatt reactors in 1975, but withdrew without completing either after the fall of the late Shah in 1979. The site on Iran's southern Gulf coast was bombed several times during the 1980-88 Iran-Iraq War, and in 1995, a Russian firm won a $1 billion deal to construct a single 915-megawatt reactor, which it completed in March 2009.
Russia dragged out the fueling process as it joined the U.S., the European Union and China in pressing Iran to suspend the Natanz uranium enrichment facility, which Iran built with technology sold by a Pakistani-led smuggling ring and hid from U.N. International Atomic Energy Agency inspectors for 18 years.
Much of the concern over the Bushehr reactor centers on whether technicians could secretly divert spent fuel assemblies removed from the reactor during refueling and separate plutonium from them through a process known as reprocessing.
U.S. officials and other experts dismissed that possibility as highly unlikely, saying that such diversions would be extremely difficult as IAEA inspectors and monitoring devices will keep the site under round-the-clock surveillance.
"There are 25 tons of fuel rods that would be discharged every year," the White House official said. "You can't pick them up and put them in your pocket."
Even so, he said, "I don't know if I'd say (that IAEA monitoring is) fool-proof."
He and other experts said there's no evidence that Iran has the knowledge, ability or the facility needed to extract plutonium from spent fuel rods, which would first have to sit in water for as many as four years before they're cool enough to handle.
"It's implausible to me that the Iranians would see that it was advantageous to go this route. It would expose them to attack for too long," said Frank von Hippel, a Princeton University nuclear physicist who served as a White House science adviser for former President Bill Clinton.
Von Hippel also said the plutonium produced at the kind of reactor at Bushehr wouldn't be "weapons grade" and that the Iranians "couldn't be confident" that warhead made from such material would work.
Sokolski said that diverting the spent fuel rods without detection is possible.
A study by the IAEA itself, he said, found that agency monitoring devices have been spoofed in the past, about two-thirds of the cameras at Bushehr won't provide real-time pictures, and the Iranians could divert one fuel rod at a time and reprocess the contents in a facility small enough to conceal inside a warehouse.
"You are banking on the come that you are going to catch this," he said.
Other experts, however, said they doubt that Iran would want to pay the economic and diplomatic price of enraging Moscow by diverting spent fuel rods that are supposed to be returned to Russia, or cutting up fresh fuel rods and using the low-enriched uranium fuel in them as feed stock for the Natanz enrichment plant.
"It wouldn't just alarm the Russians, but of course it would mobilize the entire international community," the White House official said.
Paul Brannan of the Institute for Science and International Security said Iran wouldn't risk jeopardizing its Russian fuel supplies because it lacks the capacity at Natanz or the manufacturing capabilities to make its own fuel for Bushehr.
"Bushehr is a power reactor," he said, "and that it what it's going to be used for."
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