Fluoride Action Network

The green salt mystery

Source: The Guardian (UK) - Global Security Blog | November 17th, 2009 | By Julian Borger
Industry type: Nuclear Industry

A short note on the IAEA’s report to its board of governors on Iran yesterday. It is marked by the impatient and sceptical language that has become an increasingly regular feature of the agency’s Iran reports.

That scepticism shines brightest in the section about the Qom enrichment plant which IAEA inspectors saw on October 26 and 27. The report quotes from an Iranian letter saying that construction started in 2007, on a site allocated by the “Passive Defence Organisation” – presumably in charge of hiding things under mountains.

The report notes drily that “there had been construction at the site between 2002 and 2004, and that construction activities were resumed in 2006 and had continued to date.”

And the headline-grabbing line follows soon after:

The Agency also indicated that Iran’s declaration of the new facility reduces the level of confidence in the absence of other nuclear facilities under construction and gives rise to questions about whether there were any other nuclear facilities in Iran which had not been declared to the Agency.

In particular, the IAEA is looking for evidence of a covert uranium conversion plant. The thinking is as follows – if Qom was intended as a secret site to produce weapons grade uranium, it would have to have a supply of uranium hexafluoride gas to be enriched. This could not come from the conversion plant in Isfahan because its stock is monitored by the IAEA. So if Iran was building a complete parallel fuel cycle, Isfahan would have a shadow plant somewhere.

That line of enquiry has refocused the IAEA’s scrutiny of what is known as the “Green Salt” project – a small scale method of converting uranium dioxide to uranium tetrafluoride (also known as green salt) a half-way stage to hexafluoride.

When asked about this project, Iran has said it was scrapped, as its technicians had mastered the technology for large scale conversion at Isfahan. IAEA inspectors are now wondering whether the small-scale method might have been intended for covert conversion facilities in places unknown.