MARY LOUISE KELLY, HOST:
Among the promises made when the leaders of North and South Korea met last week was this, a vow by North Korea's Kim Jong Un to shut down his country's nuclear test site and to do so as soon as next month and invite international journalists and other observers to witness it. Well, the site is named Punggye-ri. It is where North Korea has conducted all six of its nuclear tests. To learn more about it, we have called Patrick McEachern. He's a former State Department diplomat now at the Wilson Center. Welcome to the program.
PATRICK MCEACHERN: Thank you. It's a pleasure to be with you.
KELLY: Tell us what this test site looks like. I mean, where is it in North Korea, and what's the terrain? Describe it for us.
MCEACHERN: Sure. North Korea's only known test site is basically three tunnels underneath a mountain up by the Sino-North Korean border. So it's in the far north of the country, as far as - away as possible from U.S. and South Korean military assets.
KELLY: And away from big population centers too, it sounds like.
MCEACHERN: Yes, that's right. The test sites came into sharper relief after, as you mentioned, the first nuclear tests back in 2006. And they've been very closely watched since that time.
KELLY: I want to follow up on something you said there. You described this as North Korea's only known nuclear test site. There might be others?
MCEACHERN: Yeah. We certainly don't know if there are others. And so that's one of the important points to keep in mind when we talk about the fact that this known nuclear test site is going to be closed down. There's certainly the possibility that the North Koreans decided to tunnel somewhere else.
KELLY: So how big a concession is it for the North Korean leader to say we're going to shut it down? I mean, what is its significance within the broader nuclear program of the country?
MCEACHERN: From a technocratic standpoint, it's a very limited concession. But I think it's important to keep the - two things in mind. First, this was a unilateral concession that the North Koreans offered a few days before the inter-Korean summit. So it was really a symbolic effort that was intended to create the right tone for that inter-Korean summit that just took place. And so in that regard, I think it had its political effect. But I don't think it - we should focus on it too much as a significant step towards North Korean denuclearization.
KELLY: Let me ask you this. There's been discussion, particularly after the last nuclear test North Korea carried out just this past September, discussion of something called tired mountain syndrome. Explain what that is.
MCEACHERN: Yeah. So there's been, as we mentioned, all six nuclear tests at the same spot. So you have some wearing-out of those tunnels, and there is even some suggestion after the last nuclear test in September that one of those tunnels may already be collapsed. We think that the nuclear test site is probably still operational, but how much longer it can conduct nuclear tests in it safely is an open question.
KELLY: So bottom line, Kim Jong Un says he's going to do this. He says he's going to do this in the next few weeks. What will you be watching for?
MCEACHERN: Yeah. I fully expect that he will blow up these tunnels by the end of May. There is going to be a verifiable way to see it. We'll have journalists and foreign experts there. The important thing to look out for though is when North Korea decides to cease its operations at its nuclear production facilities and invite in inspectors from the International Atomic Energy Agency. Those will be the way that we'll really be able to verify their nuclear shutdowns.
KELLY: So this as a gesture, perhaps an important gesture, but a symbolic one. You'll be watching for other things on the program in the weeks and days to come. Patrick McEachern, thanks so much.
MCEACHERN: It's my pleasure. Thank you for having me.
KELLY: He's a former intelligence analyst at the State Department, currently a fellow at the Wilson Center.
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