Aju Business Daily

Mt. Mantap in the Punggye-ri site where Pyongyang conducted its sixth and most powerful nuclear test on September 3 has revealed "widespread observable surface disturbances", according to 38 North, the website for a U.S. research institute.

"It is not surprising that there were a number of post-test earthquakes," 38 North said, adding such tremors may have caused some concern about "Tired Mountain Syndrome".

However, the site's complete abandonment as a whole remains "unlikely" for the time being, given the presence of additional test portals, the website said, citing U.S. nuclear test history at the Nevada Test Site.

Despite numerous post-test earthquakes, the Nevada site was not abandoned for nuclear test purposes until a nuclear test moratorium took effect in October 1992, 38 North said.

"Such historical precedent, combined with the presence of two other, as yet unused tunnel complexes within the test site, leads us to conclude that there is no valid reason to assume that the Punggye-ri test site is unable to contain additional underground nuclear tests."

At Punggye-ri, the presence of two other test tunnel complexes "provides sufficient means to continue testing at the site irrespective of test-induced effects to Mt. Mantap," 38 North said.  So far, Pyongyang has claimed no radioactivity was released from the test site.

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