North Korea Capabilities Update I: The Nuclear Fuel Cycle



As we are waiting to see whether UNSC Resolution 2270 will have any effect, it is worthwhile to collate what we know from a variety of sources about North Korea’s nuclear and missile capabilities. Multiple theories exist about the big push that Kim Jong Un is making with respect to these programs, none altogether mutually exclusive. One is that he is seeking leverage in advance of being constrained to negotiate. A second is that the weapons program has become a key pillar of consolidating power domestically, both with respect to the military and in the larger public as a symbol of regime capability and strength.

Relatedly is an interpretation I find increasingly plausible in advance of the 7th Party Congress: that the country has broken out permanently and is seeing to cap off a basic deterrent that would permit a partial demobilization of conventional forces and a refocus on economic issues (in addition to Lee Sigal, Robert Carlin has parsed evidence on this last possibility).

Whatever the motives, North Korean capabilities are not standing still. Both for those that want to get back to negotiations and those wishing to ramp up sanctions, North Korea’s capabilities suggest the need for urgency. But it is more likely that we are entering a different world in which dismantlement is not going to happen and the question becomes whether we can accept negotiations over much more modest goals. In this series, I dissect what we know about current capabilities, starting with


In September, the Director of the Atomic Energy Institute claimed that “all the nuclear facilities in Yongbyon, including the uranium enrichment plant and 5 MW graphite-moderated reactor, were rearranged, changed or readjusted and they started normal operation.” What does this mean? Among the more granular monitoring of Yongbyon is that done by “the good ISIS”—the Institute for Science and International Security—based on satellite imagery. Their recent reports can be found here. From mid- 2013 when it was again restarted to mid-2014, the 5MWe reactor appears to have operated at near full power. ISIS assessments since that time have painted a more a mixed picture. The 5MWe reactor is still judged operational, but not fully so on the basis of indicators such as water discharge, steam venting from the turbine building and the pattern of melting snow that would indicate heat emanating from the structures.

Nonetheless, as Director of National Intelligence James Clapper testified in February, even intermittent operation would imply continued accumulation of plutonium in the uranium fuel that would at some point have to be extracted by transporting it to the so-called Radiochemistry Laboratory for reprocessing. Such movements are pretty much impossible to track, but ISIS reports argue that activities at the proximate coal power plant are correlated with activities at the reprocessing facility. They conclude that North Korea “has separated, is separating, or will soon be separating” plutonium from the irradiated fuel. Moreover, since the reprocessing facility was expanded in 2014—and because it was designed to handle spent fuel from the unfinished 50MW reactor—capacity is not a constraint; in another report, ISIS estimates that all of the fuel in the 5MW reactor could in principle be reprocessed in 3-6 months. 

In its most recent estimate of total stocks (as of end of 2014), David Albright put the stock of plutonium at 30-34 kilos, With the range for a single plutonium nuclear weapon ranging from 2-5 kilograms, the estimates also show some spread but with sophisticated analysis of frequency distributions giving an estimate of enough plutonium for 8-11 weapons. 

The new light water reactor remains a mystery. In September, the the IAEA annual report on the country concluded that “there have been no indications of the delivery or introduction of major reactor components into the reactor containment building.” ISIS concurs that the LWR is not operational, and may even have been redesigned.  

Perhaps the central uncertainty in North Korea’s entire weapons program is the status of its uranium enrichment program: is there a second facility or not? (Uncertainty about a second facility is one reason why a number of critics note that freeze proposals centered on Yongbyon are of little value; we don’t know what is being left unfrozen). But we do know that the building housing the reported centrifuge enrichment facility within the Yongbyon Nuclear Fuel Rod Fabrication Plant was nearly doubled in floor size in 2014. Moreover, the IAEA claims to have observed evidence of mining and milling at the Pyongsan uranium mine and the Pyongsan uranium concentration plant; the raw material is there.

In projections that simply extrapolated low, medium and high estimates of production of all fissile material, Albright projected a nuclear arsenal in 2020 that could have from as few as 20 to as many as 100 weapons. If the upper end of this range seems implausible—if only for reasons of diminishing marginal utility—the lower end certainly strikes us as fully plausible if we qualify the estimate to what it would be possible to produce. 

Next time: developments at the test site, prospects for a fifth test, miniaturization, doctrine and stability.

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