N.Korea Details Shutdown Nuclear Test Site

North Korea's Foreign Ministry on Saturday described how the regime intends to dismantle its nuclear test site in Punggye-ri, North Hamgyong Province.

The first step will be using explosives to collapse the underground tunnels used to test nuclear weapons. North Korea has dug at least four tunnels under Mt. Mantap in Punggye-ri.

The No. 1 tunnel on the eastern side of the mountain, which was used in the North's first nuclear test in 2006, and tunnel No. 2 to the north, which was used in the second to sixth tests, have already collapsed and are apparently no longer in use. Tunnels No. 3 and 4, which are on the west and south side and were dug more recently, are still apparently usable.

There is a strong chance that tunnel No. 2, the most-used one, has been contaminated by radiation, and experts say it will be difficult to set up explosives there even if workers wear protective suits. That means explosives can only be set up at the mouth of the shaft.

"The ground layer underneath Mt. Mantap has already collapsed, so any haphazard attempt at blowing it up could cause radiation leaks to the surface."

Some experts warn that underground hollows measuring hundreds of meters across that were formed by the nuclear blasts could collapse, causing tremors or even landslides, but others say radiation leaks could be contained simply by sealing off the entrances. More than 100 m of the entrances would have to be filled up to render the tunnels permanently useless.

The North will then demolish the buildings at the test site and formally close the entrances to the site. There are dozens of buildings near the tunnel entrances and south of the mountain.

"Security personnel and research staff will be evacuated simultaneously with the dismantlement of the test site so that the surrounding area will be shut down," the ministry said.

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