North Korea appears to have restarted nuclear reactor at Yongbyon, says IAEA

North Korea appears to have restarted the reactor at its plutonium-producing 5 MWe Yongbyon Experimental Nuclear Power Plant, the International Atomic Energy Agency (IAEA) said in a 27 August report, noting that Pyongyang's nuclear activities “continue to be a cause for serious concern”.

In the report, which covers developments on North Korea's nuclear programme since September 2020, the IAEA noted that while no signs of reactor operation had been observed since early December 2018, there have been indications “consistent with the operation of the reactor”, including the discharge of cooling water, since early July.

The agency also said that the steam plant that serves the radiochemical laboratory at the Yongbyon nuclear research facility was operational from mid-February until early July: a “significantly longer” period than that observed during possible waste treatment or maintenance activities.

“The five-month timeframe is consistent with the time required to reprocess a complete core of irradiated fuel from the 5 MW(e) reactor,” said the IAEA, citing design information it had received from North Korea on the laboratory in 1992.

This timeframe is also consistent with previous reprocessing campaigns announced by Pyongyang, stated the organisation, noting that in 2003, 2005, and 2009 North Korea had disclosed reprocessing campaigns at the radiochemical laboratory, “each of which had lasted approximately five months”.

The IAEA also pointed to continued internal construction activity at the light water reactor (LWR) at Yongbyon, including deliveries of materials and the presence of construction vehicles. However, the agency said that no additional transfers of major reactor components have been observed, adding that, based on the information currently available, it is not possible to estimate when the LWR could become operational.