Commercial satellite imagery from June 21 indicates that improvements to the infrastructure at North Korea’s Yongbyon Nuclear Scientific Research Center are continuing at a rapid pace. Modifications to the 5 MWe plutonium production reactor’s cooling system appear complete, but a less-than-normal cooling water discharge from the outfall pipe makes a determination of the reactor’s operational status difficult.
The status of the Radiochemical Laboratory—used to separate plutonium from spent fuel rods—remains uncertain, although the associated Thermal Plant has likely continued operations, and a small non-industrial building of an unknown purpose has been newly erected near the cooling tower.
Construction continues on support facilities throughout other operational areas of Yongbyon, especially at the Experimental Light Water Reactor (ELWR), where the new engineering office building appears externally complete and a small building similar to the one observed at the Radiochemical Laboratory has been erected.