Chris Hill’s testimony before the Senate has a couple of big, big developments (with the time stamps for the video) — clearing North Korea on the issue of the aluminum tubes (though not the entire uranium enrichment program) at 56:37 and explaining the cause of the delay in unloading the fuel rods from the Yongbyon reactor at 1:27:24
The bottom line in both cases is that, although the disablement and declaration process are not perfect, they are working very well. And, as a matter of personal satisfaction, Hill’s comments vindicate some of the things we’ve been surmising on this blog.
The aluminum tubes weren’t for a centrifuge program. Gee, where have we heard that before? Hill testified that the massive shipment of aluminum tubes believed to be for a clandestine enrichment facility were actually for a “conventional weapons system.”
That doesn’t absolve North Korea of cheating with a small Uraium Enrichment Program (UEP), but remember the issue in 2002 when we walked out on the Agreed Framework was that the North Koreans had a massive uranium program based on that shipment of aluminum tubes. I covered this issue in an early post for Danger Room:
Then, in the summer of 2002, the U.S. intercepted an ass-load of aluminum tubes bound for North Korea. That’s when the Bush Administration freaked. They started arguing that North Korea had gone from a little cheating (in the form of an R&D program) to a massive production program that might produce one or two nuclear weapons as early as 2005.
It also appears, as Chris Nelson first reported, that reports of uranium contamination on the tubes have been resolved. Although Hill didn’t explain how, James had a great post, Analyzing Nork U, that looked at the science behind analyzing uranium contamination.
Unloading the Fuel Rods Hill also testified that the delay in unloading the fuel rods from the Yongbyon reactor was an issue of getting the cooling pond ready and that reports of a “slowdown” in disablement mean that the North Koreans are working one, rather than three, shifts a day to remove the fuel rods.
This was what I surmised in my posts, It’s All About Water Chemistry and Norks Miss Deadline; Slow Disablement.
AHM | February 9, 2008
Well, there are tubes and there are tubes. I’d want to know if he was referring to the intel on the tubes that triggered the 2002 crisis, or the ones intercepted in April 2003 (see
Joby Warrick. N. Korea Shops Stealthily for Nuclear Arms Gear; Front Companies Step Up Efforts in European Market. Washington Post, page A19, August 15 2003.)
The latter were sized correctly for P-2 casings if cut in half (see Mark Hibbs. Urenco tells court aluminum tubing ordered for DPRK fit its centrifuge. Nuclear Fuel, 28(24):8, November 24 2003.)
If it’s the latter ones he’s talking about, that’s much more interesting than the ones they thought were being procured in 2002 (although it’s also possible that they’re the same tubes…)
Andy | February 9, 2008
If the aluminum tubes were for a “conventional weapons system” exactly how did they become contaminated with uranium?
SQ | February 10, 2008
Hill in his testimony mentions two NK weapons systems, which seems consistent with two types of tubes. One, described in the hearings “as an artillery-type system,” did not work, according to Hill. Presumably this means artillery tubes. Another conventional military use for aluminum tubes, as we all know from the case of Iraq, is in making rocket bodies.
This is a stunning development, and, in light of all that followed this failure of intelligence, grotesque.
Rwendland | February 11, 2008
From the Yongbyon spent fuel reprocessing, NK will have depleted uranium – so-called Magnox Depleted Uranium (MDU) in the UK to differentiate it from enrichment plant DU. I wonder if NK has used that in any conventional armour-piercing weapons? A possibility for contaminating other equipment like aluminium tubes for rockets.
Eli | February 11, 2008
I got a different sense of what Hill meant when he was talking about the tubes. He did say that they were currently being used for either of those conventional weapons systems. However, he also alluded to the fact that his team believes that the tubes were not brought into the country for the purpose of being used in the first system. Now this creates a strange ambiguity. Is he implying that they were supposed to be used for the second system instead? But if this is so, why did they waste some of them on the first system that did not work and that the materials did not seem proper for? Or is he implying that the North was trying to create a reason for why they had purchased the tubes and after not being able to make the first system work and create the sense plausible deniability they were seeking, they moved them to the second system that would be able to properly use the tubes?
In either case, it does point to the fact that the tubes are NOT being used for a currently operating HEU program and we should stop dragging our feet on this point. However, if the second interpretation holds true, it does seem fairly damning about what their original intent was.
SQ | February 11, 2008
One possible explanation for the uranium on the tubes (as noted in the Kessler story) was cross-contamination from Pakistani equipment supplied to North Korea. As we have learned from IAEA reports on Iran and Libya, Pakistani uranium has a distinct isotopic signature. How it got that signature, which involves the man-made isotope U-236, I would like to know, but that’s another story.
Bruce Klingner | February 11, 2008
What Chris Hill meant to say was at variance with what a lot of media have reported. I attended Chris Hill’s hearing and was puzzled by the disconnect between his seeming acceptance of the aluminum tubes as non-UEP and earlier reports of some tubes being contaminated with uranium (independently confirmed in my conversations with government sources). I called State Department who clarified that what Hill was trying to say was that North Korea asserted that the tubes WERE being used (note emphasis on current use without any mention by Pyongyang of potential previous use) for two conventional artillery systems. (My assumption is that it must be for multiple rocket launcher vice tube artillery). Chris was not offering a judgement as to whether the US accepted that assertion since the US Intelligence Community assessment remains classified, as does its view on the uranium contamination. I reviewed the tape and think he could have more carefully articulated the distinction.
Andy | February 11, 2008
SQ,
Yes, but that previous contamination was on centrifuge-related equipment. How does that type of material end up on something that’s supposedly for conventional use only? Even if the source of the contamination is Pakistani ISTM we still need to know the how and why of how that material got onto “conventional” aluminum tubes.
SQ | February 12, 2008
Andy:
The answer would seem to be, storage in the same location. Which is a suspicious coincidence…
Bruce:
Thanks for the clarification. What you are saying comes across on a second viewing. If I have it right now, Hill is saying that one set of tubes entered the country for one purpose, then were used for a non-working weapons system, then were used for a second weapons system.
That’s quite different from my initial impression.
Rwendland | February 12, 2008
SQ, isn’t the usual source of U-236 (and U-232) from enriching the uranium output of a spent fuel reprocessing plant? I don’t know much Pakistan nuclear history, but I thought they only got into reprocessing in the late 1990s. Bit of a puzzle – is there any possibility NK sent reprocessed uranium to Pakistan for enrichment before the Agreed Framework came into place, before 1994, and U-236 from this got onto Pakistan’s centrifuges? NK must have been short on natural uranium to do this, and I’m not sure HEU heavy in U-232 and U-236 would be any good for weapons.
UK Magnox reprocessed depleted uranium has about 0.06% U-236, 17,000+ tonnes of which was subsequently enriched into AGR fuel. Reprocessed enriched fuel has about 0.31% U-236 (and 0.9-1.3% U-235). Source: this NDA PPT presentation about what to do with all this UK U/Pu, and this IAEA report has more detail.
NB If NK did do enrichment R&D, it is quite possible this was with a view to producing LEU for the Agreed Framework PWR reactors. They must have been concerned about economic sanctions once they had 2GW of PWR power dependency. If you already have Pu production and implosion bombs, why worry unduly about a HEU route?
SQ | February 12, 2008
Rwendland,
Yes. To the best of my knowledge, U-232, U-233, U-236, and U-237 are all reactor products, whereas U-234, U-235, and U-238 occur in nature. (There’s a handy primer on U here: http://www.iaea.org/NewsCenter/Features/DU/du_qaa.shtml)
James Acton has recently educated us about FT-TIMS. That is presumably the technique that the IAEA used to produce the results depicted in the striking graphic at the bottom of Page 5 of Annex 1 of the June 2004 IAEA Board Report on Iran: http://www.iaea.org/Publications/Documents/Board/2004/gov2004-34.pdf
If I am interpreting it correctly, the cluster of dots in the upper right is traces of HEU of Russian origin that arrived in Iran as contamination on equipment. The cluster of dots in the lower left is traces of LEU of Pakistani origin, which also arrived in Iran as contamination on equipment. The proportion of U-236 in the Pakistani traces is slight, but noticeable.
Maybe this is not as much of a puzzle as it seems. There are claims in the open literature that Pakistan has had a small reprocessing facility at PINSTECH since the early 1980s.
If we must look to foreign sources, though, I wouldn’t favor North Korea. There are other countries that have reprocessed far more spent fuel.
Sandy | February 26, 2008
If a comment of mine just came through please hold it. I see from a further look at the IAEA report that the distinction between U-236 and 36% enriched U is clear, although the situation remains murky. 36% HEU + U-236 might be a combination suggesting Russia as the source, but I’ll wait for the tech experts to opine.
Sandy