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North Korean Nuclear Test Preparations: An Update

27 April 2012

Recent press reports on the impending North Korean nuclear test have been ambiguous. Some have quoted reliable sources that a test is imminent. Others have stated that there are no obvious signs that a test will happen soon. The most recent commercial satellite imagery available of the Punggye-ri Nuclear Test facility supports the contention that preparations are continuing and that the North Koreans are preceding as if the test go-ahead decision has already been made. The imagery does not, however, give any indication of when that detonation may take place.

Satellite pictures from April 18, 2012 are the latest in a series of photos that document continuing preparations for an upcoming nuclear test. A March 8, 2012 image shows that North Korea dumped spoil material—excavated from the test tunnel—and created two adjacent teardrop shaped mounds, together covering an area that is 300 square meters greater than observed in 2011 (indicating that the tunnel has been expanded since then) (see figure 1). Overall, some 8,000 cubic meters of rubble have been excavated at the site covering 4,000 square meters. The photo also reveals a dark-toned material situated adjacent to the tunnel entrance which may be stemming material intended to eventually seal the tunnel, but is more likely mud impeding work at the site.

Figure 1: Punggye-ri Nuclear Excavation (March 8, 2012)

GeoEye satellite image/analysis by Allison Puccioni, IHS Jane’s

The imagery, taken after a recent snowfall, shows significant activity: the road system around this remote base is entirely snow-free, indicating extensive vehicle traffic. The central courtyard of the operations base is also clear of snow and there are several signatures of generator activity. A rail line for mining carts (also visible in subsequent pictures) that has been used to bring out and dump excavation material, also known as “spoil,” is visible. Vehicles, structures and unidentified objects are on top of and around the spoil pile, perhaps to prepare the test device and diagnostic equipment in the test chamber. Once that is done, the mining carts can be used to deliver stemming material and spoil to seal the shaft during the final test preparation stage.

A satellite photo from March 27, 2012 shows that there is new vehicle tracking on the spoil pile from the road to the tunnel portal and small pieces of unidentified equipment were also newly placed on top of that pile (see figure 2). It is unclear at this time what this new activity specifically represents with respect to nuclear test preparations.

Figure 2: Punggye-ri Nuclear Excavation (March 27, 2012)

GeoEye satellite image/analysis by Allison Puccioni, IHS Jane’s

The latest imagery, taken April 18, 2012, documents continuing preparations for an upcoming nuclear test and shows a train of mining carts on top of the spoil pile and random unidentified structures or objects on or near the piles (see figure 3). Based on an examination of previous satellite photos, their position and number appear to vary on a day-to-day basis, indicating the continued movement of vehicles, structures and other objects on or near the spoil piles at the mouth of the test tunnel. According to one press report on April 21, the North had completed the removal of the large spoil pile near the test site, probably to seal the tunnel for the explosion. However, this imagery shows the size of the pile largely unchanged. Whether the test device has been emplaced in the chamber and stemming with other material has been completed, remains unclear.

Figure 3: Most recent satellite picture of Punggye-ri Nuclear Test Facility (April 18, 2012)

GeoEye satellite image

The April 18 photo illustrates a drainage ditch that passes water flow from a gully around the spoil pile that blocked the original path. Without such a ditch, the entrance would be muddy, making it more difficult to work in the area. The following 3D ground level rendering of the site highlights the steepness of the terrain and the need for such a ditch.

Figure 4: 3D Model of Punggye-ri Nuclear Test Facility

Google Earth/GeoEye image 2010/rendering by Los Alamos National Laboratories

Figure 5: Successive March – April 2012 imagery shows increasing activity around spoil pile.

Satellite imagery: GeoEye.

This article is a “38 North” exclusive with contributions by Jack Liu and Allison Puccioni.

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13 Responses to “North Korean Nuclear Test Preparations: An Update”

  1. SuanneM. says:

    […] North Korea conducts its third nuclear test (possible). Punggye-ri, North Korea. […]

  2. […] North Korea conducts its third nuclear test (possible). Punggye-ri, North Korea. […]

  3. […] North Korea conducts its third nuclear test (possible). Punggye-ri, North Korea. […]

  4. […] onder het water zit) maken duidelijk dat deze regio nog voor de nodige levendigheid gaat zorgen. Noord-Korea lijkt intussen haar oude spiel weer opgepakt te hebben. Een derde kernproef lijkt aanstaande. […]

  5. […] to try to pinpoint the location of the 2006 and 2009 North Korean tests, and point to evidence first published by the 38 North website in April of a third major tunnel in the same Punggye-ri area, which the authors assess is […]

  6. […] North Korea appears to have an underground tunnel ready for testing. Commercial satellite imagery shows a recently excavated “south portal” for a tunnel in Punggye-ri, situated very close to […]

  7. […] North Korea conducts its third nuclear test (possible). Punggye-ri, North Korea. […]

  8. […] agreed that North Korea faces further isolation if it continues its pursuit of a nuclear program. Activity is ramping up at North Korea's nuclear test site, a sign that the country is preparing for… is ramping up at North Korea's nuclear test site, a sign that the country is preparing for a test, […]

  9. […] North Korea conducts its third nuclear test (possible). Punggye-ri, North Korea. […]

  10. […] The 38 North website of the U.S.-Korea Institute of the Johns Hopkins School of Advanced International Studies posted three satellite photos showing the progression of work at the blast site over the last seven weeks. […]

  11. […] 372 km (231 miles) northeast of the Three Revolutions Exhibition Hall, excavation and construction work proceeds.  The ongoing activity suggests that preparations are under way for the DPRK to conduct a third […]

  12. […] im luftleeren Raum ist, zeigte sich spätestens am vergangenen Freitag, als die Fernaufklärer von 38 North mal wieder ein paar Ergebnisse ihrer Arbeit vorlegten. Danach konnte man auf dem Nukleartestgelände in Punggye-ri zwischen dem 08.März und dem 18. […]

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Credit for photo of young North Korean girl: T.M. All rights reserved, used with permission.