Evidence suggests that North Korea is ramping up production of plutonium and uranium nuclear materials at the radiochemical laboratory and uranium enrichment facility in the Yongbyon nuclear complex, as it has begun full-scale operation of the experimental light water reactor this summer. Recently, major foreign media outlets covering North Korea have debated and verified the reliability of the thermal infrared analysis of the Yongbyon facility presented in a Daily NK column I published in May. This article summarizes thoughts and opinions on this matter, and also examines what is behind the intermittent night lights observed in Yongbyon through night-time luminosity images.
◆ Yongbyon reactor and light water reactor appear to be operating
Recent conditions at the Yongbyon reactor and light water reactor area were examined using Maxar’s GeoEye-1 satellite imagery (40 centimeter resolution). In the June 19 satellite photo, heated cooling water from the reactor and light water reactor operation is clearly identified being discharged into the Kuryong River through two pump stations, accompanied by white foam. This marks the 16th cooling water discharge detected this year. As it continues to appear in satellite images since late April, the experimental light water reactor appears to have entered full-scale operation. The South Korean Ministry of National Defense had previously predicted that the Yongbyon light water reactor would enter normal operation in or around the summer months.
Below the second pump station, a yellow substance spread out in a rectangular shape can be seen on the ground. This could be wheat or barley being dried after harvest. In North Korea, mid-June is the peak harvest time for wheat and barley in the fields, followed typically by planting corn as the year’s second crop. Soldiers and workers guarding the Yongbyon nuclear facility appear to be engaging in farming activities in empty spaces within the complex as food rations are insufficient.
◆ Analysis of Yongbyon thermal infrared satellite imagery
The temperature distribution within the Yongbyon nuclear complex was examined by analyzing thermal infrared images (100 meter resolution) taken by the U.S. Earth observation satellite Landsat-8. Around 11 AM on June 17, the Yongbyon area had an average temperature of 24°C, with a low of 19°C and a high of 32°C, indicating that the weather was not particularly hot. Thermal infrared analysis showed that the radiochemical laboratory was emitting high heat of 31-32°C, while the uranium enrichment facility and thermal power plant were emitting high heat of 28-29°C, which is shown in purple.
This high heat emission from the Yongbyon facilities suggests that North Korea is accelerating its nuclear material production capabilities and actively operating facilities, following North Korean leader Kim Jong Un’s directive emphasizing “the need to accelerate important activities and production activities for strengthening nuclear forces.”
Recently, major foreign news media, including Newsweek, have debated and verified the reliability of the thermal infrared analysis of Yongbyon facility operations. This seems to have been triggered by a column I wrote, which was translated into English and published on May 23. In response, 38 North presented a different opinion regarding the content in the author’s column that “the Yongbyon radiochemical laboratory was found to be operating, emitting high heat in thermal infrared analysis,” stating that “the facility was not operating at that time.” The argument put forward by 38 North is that, as shown in the left photo below, the boiler room of the thermal power plant was under maintenance at the time. They argue that because the boiler room had its roof removed for repair work, the connected radiochemical laboratory (also known as the reprocessing facility) was consequently unable to operate and had stopped. I’d like to examine this argument further below.
◆ Repairs of the boiler room in the Yongbyon thermal power plant
There is a thermal power plant about 500 meters away from the Yongbyon radiochemical laboratory. It burns coal to operate steam boilers, and the resulting steam is used to turn turbines to generate electricity. The electricity is used to operate the radiochemical laboratory facility.
GeoEye-1 satellite photos taken on May 14 showed that the thermal power plant boiler room roof had been removed. There are three steam boilers, and 38 North claims that since they were stopped for maintenance, the radiochemical laboratory would not be able to operate at the time. In a June 19 satellite photo, the building roof appears to be covered again. This suggests that repair work on the thermal power plant boiler room has been completed.
I shared my opinions on this turn of events with a defector familiar with the internal situation in North Korea. Daily NK provided an introduction to this defector, who is a former member of the Korean People’s Army. We sat together in front of a computer, zooming in on satellite photos to facilitate an in-depth discussion. The defector told me that “the radiochemical laboratory does not completely stop operation due to steam boiler room repairs.” As would be the case anywhere, but especially in North Korea, he emphasized that important infrastructure (especially nuclear facilities) must maintain constant operation and never stop. If repair work is to be done, it would be done while maintaining partial operation of the facility, dividing the work, rather than completely stopping the entire related facility. Halting operations completely would be unthinkable, and if it happened, the facility manager would face accountability at the risk of their life.
Taken this all into account, I argue that the main power source for the Yongbyon nuclear facilities, including the radiochemical laboratory, is separate from the thermal power plant, which is only a backup power source for the facility.
◆ Mysterious late night lights at the radiochemical laboratory
Night-time luminosity images captured lights at the Yongbyon radiochemical laboratory late at night. Mysterious lights were identified around 1:30 AM on March 23 and June 26. Night-time luminosity images (VIIRS) are taken daily, so considering dates that might have been missed, the appearance of night-time lights at the Yongbyon facility was likely more frequent. The question is what is happening there at 1:30 AM? It could be facility maintenance or renovation, or it could be the covert importation of spent fuel rods at night for plutonium extraction reprocessing. Since the international community constantly monitors the facility through satellites, North Korea could secretly bring in spent fuel rods at night to avoid detection. This suggests that North Korea is carrying out dangerous illegal activities that it cannot do openly, playing hide-and-seek with the international community. The several cases of satellite launches conducted at North Korea’s west coast satellite launch site can be cited as recent examples. North Korea attempted satellite launches at night, particularly in the early morning hours, to evade international satellite surveillance.
Meanwhile, influential foreign media outlets recently released an assessment about thermal infrared analysis, which is used to determine the operational status of the Yongbyon nuclear facilities. The prominent U.S. North Korea-focused website Beyond Parallel has provided an in-depth analysis of the reliability of thermal infrared data. I read the three articles with great interest. The conclusion of the series of articles evaluated the results of the thermal infrared analysis of North Korea’s Yongbyon nuclear facilities as generally reliable. The outlet explained that after obtaining and comparing Yongbyon facility operation records for over two years held by the U.N., the results largely matched those of the thermal infrared analysis. When high heat was detected in the thermal infrared data, it corresponded with the operation of the Yongbyon facilities. However, the caveat was that facilities operating at low intensity might not be detected due to weak heat emissions. They also recommended drawing comprehensive conclusions by combining thermal infrared analysis with various other data, as there are still imperfections in the analysis. This is valuable advice worth noting.
Please send any comments or questions about this article to dailynkenglish@uni-media.net.
