Another IAEA DG Report on Iran. Cue the panic.

Iran Has More Enriched Uranium Than Thought!

Iran understates uranium stocks to IAEA!

Iran holds enough uranium for bomb!

Only the exclamation points are mine. These stories are scandalous. Daniel Dombey’s father is a physicist for god’s sake!

(Joby Warrick, on the other hand, took the relatively balanced view, with Iran Easing Aspects Of Nuclear Program in the Washington Post, February 20, 2009, A14. I wonder whether his editors will give him a hard time for not writing the same thing everyone else has written.)

Obviously, Iran would have to further enrich its stockpile of low-enriched uranium to make a bomb, which would be detected (at least at Natanz). We’ve been over this before.

The bigger misconception is that Iran has somehow misled the IAEA about its stockpile of low enriched uranium. The IAEA report does not suggest that Iran failed to declare material. Here is the actual paragraph from the report:

3. The Agency has finalized its assessment of the results of the physical inventory verification (PIV) carried out at FEP on 24–26 November 2008, and has concluded that the physical inventory as declared by Iran was consistent with the results of the PIV, within the measurement uncertainties normally associated with enrichment plants of a similar throughput. The Agency has verified that, as of 17 November 2008, 9956 kg of UF6 had been fed into the cascades since February 2007, and a total of 839 kg of low enriched UF6 had been produced. The results also showed that the enrichment level of this low enriched UF6 product verified by the Agency was 3.49% U-235. Iran has estimated that, between 18 November 2008 and 31 January 2009, it produced an additional 171 kg of low enriched UF6. The nuclear material at FEP (including the feed, product and tails), as well as all installed cascades, remain under Agency containment and surveillance. [Emphasis mine.]

Important phrases:

within the measurement uncertainties normally associated with enrichment plants of a similar throughput.

remain under Agency containment and surveillance.

Nothing is f*cked here, Dude.

Within the Measurement Uncertainties

In order to know that the IAEA discovered more LEU than Iran “declared,” one needs to look at the previous IAEA DG Report. The DG stated “As of 7 November 2008, the total amount of UF6 fed into the cascades since the beginning of operations in February 2007 was 9750 kg, and based on the operator’s daily accounting records, Iran had produced approximately 630 kg of low enriched UF6.”

That’s the discrepancy: 839 kg minus 630 kg.

Fascinating. Anybody think that all these reporters carefully compared the two reports? Obviously, not.

This is spin — though not for a bad cause. More on that in a moment. Someone decided to explain they found a bunch more LEU in order to put a little pressure on the Iranians.

[Correction: My cynicism got the better of me here. I hope to write a fuller correction soon.]

Now observe the phrase: “based on the operator’s daily accounting records.” A colleague and I have been talking about this since the last report — how accurate are the operating records? We noticed, for example, that the Iranian operating records claimed that Iran was enriching to 4.9 percent, while environmental samples indicated the level was only up to 4.0 percent. Now, based on the PIV, the number turns out to be more like 3.49 percent. I guess we are the only people who have been reading the footnotes in the damned IAEA reports.

(By the way, it is worth noting that there is almost exactly the same amount of U235 in 839 kg of 3.49 percent LEU and 630 4.9 percent LEU.)

The IAEA makes clear that the discrepancy between the stockpile estimated from daily accounting records and the physical inventory is “within the measurement uncertainties normally associated with enrichment plants of a similar throughput.” As a diplomat tells Heinrich, “faulty estimates that can arise from complexities in the phased enrichment process, not to any maneuver to divert LEU out of sight.”

This is going to kind of frighten you, but large scale industrial processes are not measured in bomb units, even though that would be awesome. This same reality, in a slightly different context, gives rise to the wonderfully titled Material Unaccounted For (MUF).

Think about this way: A 164-centrifuge cascade consumes about 70 grams an hour. If you have 18 cascades, you are consuming 30 kilograms of UF6 a day. (.07 kg x 24 × 18 = 30) Let’s say that you are wrong, by one percent a day, regarding how much of the 30 kg ends up in the product as opposed to the tails. You are underestimating your production by 300 grams day — within two years, you will underestimate your production by more than 200 kg. (This is merely expository. Note that the Natanz PIV covered February 2007-November 2008, during which the number of operating centrifuges grew from 0 to 24 with uneven operating patterns.)

Remain Under Agency Containment and Surveillance

This isn’t nearly as terrifying as it sounds because accountancy is just one safeguards tool.

Containment and surveillance is another. Again, as the IAEA points out, “The nuclear material at FEP (including the feed, product and tails), as well as all installed cascades, remain under Agency containment and surveillance.”

In other words, even if you aren’t sure how much he weighs, Elvis is still in the building.

So, why the fuss? Because the IAEA only does a PIV every year or so at Natanz. Containment and surveillance are wonderful, but it is nice to occasionally check the material itself.

As a “diplomat” tells Mark Heinrich:

But the diplomats said the verified LEU figure was based on an inventory check that inspectors perform only once a year.

In theory, this means there is a risk that any smuggling of enriched uranium out of Natanz for use at a secret site might not be noticed for some time.

U.N. inspectors are discussing with Iran how to improve its operating records to prevent any repeat of such large differences in accounting in future, the diplomats said.

I actually agree that we need to improve our monitoring of Iran’s activities. So, I think it is helpful to point out how inadequate current arrangements are even if the Iranians are complying with their obligations.

But no need to stir up panic.