Both Adam and Origuy have asked me about reports of a tunnel collapse at the Punggye-ri nuclear test site. Between 100 and 200 workers are said to have died. Yonhap News, which I’ve linked, is usually reliable.
After the last nuclear test, which was much bigger than earlier ones, three seismic events were detected from Punggye-ri. This led a group of analysts to posit “tired mountain syndrome,” which is a fancy term for fracturing by the tests, leading to a need for more bracing in tunnel construction and possible damage to existing tunnels. Because it appeared that North Korea had built systems of tunnels for multiple nuclear tests, this could be a severe loss to North Korea’s program.
The tunnel collapse supports this interpretation. The number of people involved suggests that North Korea digs its tunnels largely by hand, rather than with large tunneling machines available in the West. The collapse, said to be in a tunnel under construction, also suggests that North Korea has done little bracing in its tunnels. This would work well enough in hard rock, but the fracturing may make it no longer possible.
A related fear, that the tests might activate a nearby volcano, is unlikely. Compared to natural processes like volcanoes, even hydrogen bombs look small.
North Korea has not tested a missile or a nuclear device for over a month. Problems at Punggye-ri may be the reason. This also may be part of the reason that North Korea has been threatening an atmospheric test.
Tunnel Collapse At The North Korean Nuclear Test SitePost + Comments (62)