Why Iran had a secret nuke site

Christian Science Monitor:

Iran's newly revealed second centrifuge plant hidden in a mountainside fits neatly into Tehran's nuclear program, as if it were a long-missing piece to a jigsaw puzzle that's almost complete.

That is because Western intelligence analysts and experts outside government have long suspected that if Iran wanted to produce fissile material for a nuclear weapon, it would have to do so at a hidden facility. Known Iranian nuclear sites are too closely watched to serve that purpose.

Two years ago, in its 2007 National Intelligence Estimate of Iran's nuclear intentions and capabilities, the US intelligence community concluded that "we assess with moderate confidence that Iran probably would use covert facilities – rather than its declared nuclear sites – for the production of highly enriched uranium for weapon."

Information made public so far makes it appear the new site has all the attributes this predicted covert facility would have.

1. It's hidden

First of all, it may be dug into the side of a mountain. The US government has not said exactly where the suspect plant is located, noting only that it is near the city of Qom. But outside experts have already produced satellite imagery (see a pdf of the pictures here) of a likely location that appears to be a tunnel dug into the side of a ridge on a military facility 30 miles north east of Qom.

2. It's small

A US official who briefed reporters last week said it is designed to hold about 3,000 uranium-enriching centrifuges. That is too few to produce low-enriched uranium for a nuclear power reactor.

"But if you want to use the facility in order to produce a small amount of weapons-grade uranium, enough for a bomb or two a year, it's the right size," said the US official.

3. The timing fits

In 2003, an Iranian dissident group revealed the existence of Iran's first clandestine enrichment site, at Natanz. Shortly thereafter, Tehran agreed to submit to tougher Internatonal Atomic Energy Agency scrutiny.

Then, in 2005, tunneling began at the secret site near Qom, imagery suggest. Caught once, Iran may have been trying its luck at a second attempt at concealment.

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There is more.

Does Iran really need a secret site? They seem to be pretty blatant about their objectives with the existing sites regardless of their denial about intent. Then there is the fact that they did not really fool anyone with the construction of this facility, with the possible exception of those who wrote the 2005 NIE. However, I think that was more a political document to thwart the Bush administration than are good faith intelligence estimate.