For a brief period yesterday afternoon, initial news reports had me thinking that perhaps proof had finally emerged that Iran has indeed carried out work on a nuclear weapon and was taking actions in an attempt to hide the after-effects of that work. As new details emerged, however, it became more clear that an elaborate game of cat and mouse is being played out between Iran and those who accuse them of weapon development, but overall there still seems to be no conclusive proof that weapon development at the controversial Parchin site has been carried out.

That is a pattern that has played out several times now. “Diplomats” provide anonymous information to a reporter in Vienna on new accusations about nuclear weapon development work in Iran. The first version of the story put out by the reporter contains only a vague accusation but is delivered with a sensationalized headline suggesting that new and important evidence supports the conclusion that Iran is carrying out work at Parchin aimed at developing a neutron trigger device for a nuclear weapon . Subsequent expansion of the article reveals that the “evidence” is much weaker than initially portrayed and that technical details tend to contradict the accusations for the large part.

Until yesterday, that pattern had played itself out three times since March, each with George Jahn of AP playing the role of the reporter in Vienna. First, there was the claim in March that Iran was trying to clean the Parchin site to remove evidence of work on a trigger device. It took several weeks after the initial claim, but finally a satellite image purporting to show evidence of “washing” the building at Parchin was produced in early May when David Albright displayed satellite images showing puddles in the parking lot outside the suspect building. Of course, Albright’s claim of “washing” away the radioactivity is ludicrous, as traces would remain, especially if the wash water is simply allowed to pool in the parking lot of the building. Albright and Jahn did not give up, however, and Jahn subsequently came up with a cartoon depicting the chamber (it’s even the same color as the real chamber!). The huge hole in those accusations, though, is that if the accused neutron trigger work with uranium were indeed being carried out at Parchin, then the process of neutron activation would have resulted in both the structural steel of the chamber itself and most likely the structural steel of the building housing the chamber being radioactive throughout the thicknesses of the steel. This would mean that Albright’s claims that Iran could “cleanse” the chamber and the building by grinding and washing surfaces were impossible. Instead, in order to clean the site:

The only way that Iran would be able to hide evidence of work on a neutron trigger device at Parchin would be to dismantle and remove the entire chamber. It most likely would be necessary to raze the entire building as well, since the structural steel in the building surrounding the chamber also likely would have been made radioactive by the neutrons.

Jahn’s third sensational headline followed by less sensational details related to the finding of traces of uranium enriched to 27% rather than 20% at the enrichment site at Qom instead of at Parchin, but this still fits the overall pattern.

Another aspect of attempts to clean evidence of work with radioactivity is removal of the upper layers of soil.

Yesterday, Fredrik Dahl of Reuters took over George Jahn’s role as the reporter in Vienna to release a sensational headline only for the real story to fall short of the accusations (apologies to Jahn for my initial–now deleted–tweets on this revelation, which I attributed to him when I reacted first to the headline and only later noticed the story was from Dahl and not Jahn). I have counted at least five versions of Dahl’s story as it was updated through the day yesterday and this morning. Here is complete article as it appeared in its initial form:

The U.N. nuclear watchdog showed new satellite imagery on Wednesday indicating that Iran may be cleaning a site where inspectors suspect it has carried out tests relevant to developing atomic bombs, participants at a closed-door briefing said.

One person who attended the presentation by senior U.N. nuclear agency officials for diplomats accredited to the International Atomic Energy Agency said a May 25 image showed “ground scraping activities” at the Parchin military site.

Another envoy said one building also appeared to have been removed from the site, compared with earlier images of the same place.

Last week, the IAEA said in a report issued to member states that satellite images showed “extensive activities” at the facility southeast of Tehran.

It did not elaborate, but Western diplomats say they suspect Iran is trying to remove any incriminating evidence from the site, which the U.N. agency wants to visit as part of its probe into possible military dimensions to Iran’s nuclear program.

The first headline wasn’t terribly sensationalist, mentioning only new “activity” at Pachin, but version two, which didn’t appear to have changed in the body of the story had the the new headline “Image shows buildings gone at Iran site: diplomats”, which was quite sensationalist since it was only in later versions of the story that we learned the building housing the chamber is still intact.

On first glance, and without key details that later emerged, the initial versions of Dahl’s story look like the beginning of a “smoking gun” showing that Iran had indeed carried out neutron trigger work at the site and now is trying to hide the evidence. If the explosive chamber and the building housing it were dismantled and the soil beneath and surrounding the building removed, this would be a tacit admission of the accused work and virtually confirm that the chamber was radioactive from neutron activation.

The problem is that, as I predicted, David Albright posted (pdf) the satellite images referred to in Dahl’s article before the end of the day on Wednesday and they paint a dramatically different picture of what is going on at Parchin. As the photos and the later versions of Dahl’s article (see here for the version as of this writing) indicate, the buildings razed do not include the building where it is assumed the chamber resides. Further, the soil being moved is some distance from this building and does not even include the soil beneath the buildings which were razed (the debris from these buildings still litters the building sites, demonstrating that no soil was removed). Rather than demonstrating that Iran is hiding evidence of neutron trigger work, the images to me are more suggestive of either site preparation for the construction of new buildings or work to change the pattern of runoff from a small lake (or “pond” in Albright’s discussion) situated to the north and uphill of the suspect building.

At any rate, Iran knows that the Parchin site is being watched very carefully at the current time, so these actions of razing buildings and moving soil around look to me like a bit of playing around with the “diplomats”, their obedient news reporters and David Albright, attempting to draw them into making new and unsupportable allegations against Iran. At least Dahl seems partially aware of this possibility. He did include this in the later versions of the article:

Robert Kelley, a former senior IAEA official, said that if there were any uranium traces at the site the agency’s inspectors were still likely to find them.

“If Iran is washing out the building and equipment outside, and there is actually uranium present, letting the uranium contaminated water run across the parking lot means the IAEA is going to have a 100 percent chance of finding it.”

Albright, for his part, has doubled down on his earlier accusations of cleaning that resulted in the parking lot water in yesterday’s report, rather than using the new report as an opportunity to step back from his unsupportable allegations:

This new round of activity has followed suspected cleanup activities in the explosives testing chamber building, which are visible in an April 9, 2012 satellite image published in an earlier ISIS report (figure 4).

By the way, the parking lot appears unchanged in the May 25 images compared to April 9, aside from now being dry. If soil was removed there, the parking lot was reconstructed in its original configuration, unlike the other areas where soil was moved with no actions taken to hide that activity.

As for Iran playing around with its accusers, Dahl also has this in his article:

Iran’s IAEA envoy, Ali Asghar Soltanieh, dismissed such accusations by Western officials, telling reporters after the briefing that “this kind of noise and allegations are baseless”.