Military, Nuclear Weapons

Punggye-ri Update: Continued Activity Near Tunnel No. 4

Key Findings

  • A review of high-resolution Airbus Neo satellite images from September 19 to September 29, 2022, provides details on the current observable status of the Punggye-ri Nuclear Test Facility.
  • While all preparations for a nuclear test appeared completed at Tunnel No. 3, we see new work being done at Tunnel No. 4: 1) significantly, the area directly in front of the portal shows evidence of clearing, and 2) construction of the access road to Tunnel No. 4 continues.
  • There is no new activity at Tunnel No. 3. This is expected because both the United States and South Korea assess North Korea as having finished all preparations for conducting a nuclear test using this tunnel.
  • The detected activity at Tunnel No. 4 could be part of an expansion of North Korea’s nuclear testing capabilities beyond Tunnel No. 3, or it could be a component of a strategic deception plan. 
  • The timing of a seventh nuclear test now remains solely within the hands of Kim Jong-un.

Beyond Parallel’s ongoing detailed coverage of North Korea’s WMD and ballistic missile developments continues with this report addressing observable activities at the Punggye-ri Nuclear Test Facility as of September 29, 2022.

An overview of the Punggye-ri Nuclear Test Facility, September 29, 2022. Click here to enlarge the image. (Copyright © Airbus DS 2022) Image may not be republished without permission. Please contact imagery@csis.org.

Tunnel No. 3

A high-resolution Airbus Neo satellite image collected on September 29, 2022, shows no significant changes to the area immediately outside the portal to Tunnel No. 3 (also known as the South Portal). This lack of new external developments is not unexpected as both the United States and South Korea assess North Korea as having finished all preparations for conducting its seventh nuclear test.

A short distance to the southeast of Tunnel No. 3 is an open-air lumber mill and a small storage yard. What appears to be some minor changes to the size and number of lumber/logs located here are noted in the latest image.

A September 29, 2022, view of Tunnel No. 3 at the Punggye-ri Nuclear Test Facility. Click here to enlarge the image. (Copyright © Airbus DS 2022) Image may not be republished without permission. Please contact imagery@csis.org.

Tunnel No. 4

The construction of the access road to Tunnel No. 4 (also known as the West Portal) has resumed, and the road is now cleared to the area directly in front of the collapsed portal. This area in front of the collapsed portal shows evidence of recent grading. There is no evidence in the September 29, 2022, image of any significant activity to reopen the portal. Any effort to do so will likely require rebuilding the extensive support cribbing seen above it prior to the 2018 disabling. Experts believe that the 2018 disabling only collapsed a small section of the entrance to the tunnel as was done at Tunnel No. 3. As noted in previous reports, it remains unclear whether this activity is designed to expand North Korea’s nuclear testing capabilities beyond Tunnel No. 3 or a component of a strategic deception plan.

A view of the access road leading to Tunnel No. 4 and the recent grading activity in front of its collapsed portal, September 29, 2022. Click here to enlarge the image. (Copyright © Airbus DS 2022) Image may not be republished without permission. Please contact imagery@csis.org.

Main Administration and Support Area

Continued activity is observed in the main administration and support area. Here, the construction of three support buildings appears to be complete, while one remains under construction. Additionally, two unidentified objects, which may be piles of drying grain, are observed in the center of the courtyard.

Overview of the Main Administration and Support Area, September 29, 2022. Click to enlarge. (Copyright © Airbus DS 2022) Image may not be republished without permission. Please contact imagery@csis.org.

Tunnels No. 1 and No. 2

The September 29, 2022, satellite image continues to show no activity at either of the remaining two tunnels at the Punggye-ri Nuclear Test Facility—Tunnel No. 1 (East Portal) and No. 2 (North Portal).

Overview of the collapsed Tunnel No. 2 (North Portal), September 29, 2022. Click to enlarge. (Copyright © Airbus DS 2022) Image may not be republished without permission. Please contact imagery@csis.org.
Overview of the abandoned and collapsed Tunnel No. 1 (East Portal), September 29, 2022. Click to enlarge. (Copyright © Airbus DS 2022) Image may not be republished without permission. Please contact imagery@csis.org.

Elsewhere at the Facility

In the reviewed images, no activity of significance was observed in the Command Center Area further south of the tunnels. However, minor ongoing activity to address damages from recent flooding is noted along the facility’s sole access road between the Command Center and the tunnels.