These N. Korean Reactors Light Up Danger Signals
Next Wednesday, at a coastal construction site in North Korea, diplomats from the United States, Europe, Japan, South Korea and North Korea will watch from a reviewing stand as South Korean builders pour the first concrete for the foundations of two large U.S.-type nuclear power reactors. We promised the North these reactors, known as light-water reactors or LWRs, in 1994 in exchange for the shutdown of the country's small plutonium production operation based on their own home-built reactors.
The diplomats are going to the pouring to celebrate the belief that this exchange puts more distance between the North Korean regime and nuclear weapons, perhaps even putting such weapons out of North Korea's reach. The North's home-built reactors were an easy source for bomb plutonium, but the LWRs, our State Department keeps saying, are "proliferation-resistant." Sounds almost too good to be true. Alas, it is.
Comparing reactors of the same size, we'd rather see countries build LWRs (whose name derives from their use of ordinary water for cooling). Reactors of the type North Korea copied, unlike LWRs, are continually refueled, creating constant opportunities for diverting fuel to weapons programs. To take fuel out of an LWR, you need to shut down the entire thing, and it's harder to do that surreptitiously or frequently.
But the LWRs come in large sizes and make lots of plutonium, too. The ones we're supplying to North Korea can make more than all the home-built reactors they would replace. These technical points are important and apply to similar reactors in other countries as well. Consider the parallel case of the LWRs Russia is building for Iran. The State Department thinks the reactor project could help the Iranians make bombs. Here its instinct is right. But because the State Department is caught up in its "proliferation-resistant" description of the LWRs for North Korea, it can't explain why reactors of the same type are threats in Iran. The Russians have seized on the inconsistency in the U.S. approach to defend their own project. The confusion isn't just at State. The latest comprehensive report from the Carnegie Endowment Non-Proliferation Project describes the Russian LWRs as "particularly unsuitable" for producing bomb plutonium.
In truth, LWRs could be used to produce dozens of bombs' worth of weapons-grade plutonium in both North Korea and Iran. This is true of all LWRs -- a depressing fact U.S. policymakers have managed to block out. Over the past three decades, the purveyors of the plants and diplomats looking for a neat fix for proliferation concerns have come up with a web of rationales for why the LWRs are not a security worry. We now have to cut through this tangle to get at the facts on which to base sensible policy. The basic technical information has been available for years in official reports, including those of the national laboratories, Congress and International Atomic Energy Agency (IAEA), and it tells us several important things.
• LWRs can produce large amounts of "weapons-grade" plutonium, the kind ideally suited for bombs. The ability to make bombs with the plutonium LWRs generally produce -- known as "reactor-grade" plutonium -- has been debated for 25 years. (Despite the designation, such plutonium can, with the right know-how, be used to make nuclear bombs.) What has been widely ignored is that LWRs also produce lots of what is generally accepted to be "weapons-grade" plutonium. It all depends on how long you let the fuel sit in the reactor. The less time the fuel stays, the more suitable the plutonium is for bombs. According to a Livermore weapons laboratory report written about the LWRs for North Korea, after the first scheduled refueling, about 15 months after initial start-up, a standard LWR will contain about 300 kilograms of near-weapons-grade material. That's dozens of bombs' worth. What nation needs more?
• Extracting plutonium from spent LWR fuel rods by chemical reprocessing is no longer the obstacle it once was. A 1977 Oak Ridge Laboratory internal report, widely distributed at the time, details how this might be done quickly and cheaply, at least by nations that know what they are doing. After years of training and experience, North Korea and Iran would qualify. Pyongyang already has a reprocessing plant and would need only an additional unit at the front end to cut up the long LWR fuel rods into small pieces, which could then be placed in dissolution tanks. American diplomats who defend the suitability of the LWRs for North Korea have seized on Pyongyang's lack of such a front-end cutter as a reason for us to feel secure. Because a commercial fuel "chopper" is a complex, prohibitively expensive item that few countries possess or are willing to sell, obtaining one is supposed to be an insurmountable hurdle for the North. But the reprocessing experts at Oak Ridge, who were designing a cheap, easy-to-hide facility for making plutonium for bombs, said they could use less sophisticated, readily available parts. Instead of the costly chopper, they required only one "metal-cutting saw, abrasive disk" for cutting under water. No big deal.
Altogether, the Oak Ridge engineers estimated that from the first diverted LWR spent-fuel assembly to production of plutonium metal for bombs would be only a matter of weeks. Their little plant is designed to then turn out a bomb's worth a day from typical LWR fuel. Sticking to our example using only near-weapons-grade plutonium, there would be enough for, say, a couple of dozen bombs in a couple of months. That's a pretty fast path to a fairly large arsenal.
• We can no longer assume that the threat of detection will deter would-be bomb makers from cannibalizing LWRs' spent fuel. The last refuge of proponents of the LWRs-are-proliferation-resistant view is that would-be bomb makers couldn't do all this without getting caught. The theory is that no aspiring nuclear power would risk the wrath of the world's major powers. But it's hard to sustain this view after Iraq's and North Korea's Nuclear Nonproliferation Treaty (NPT) violations, their stiff-arming of IAEA inspectors and the slow reaction of the world powers. Suppose North Korea or Iran had illicit LWR reprocessing labs ready to go before they extracted spent fuel from their LWRs. The IAEA assumes that from the first production of plutonium metal to the first bomb might be a matter of weeks. Amassing an arsenal of dozens of bombs could take a few months or less. That's a lot less time than it took to respond to Iraqi and North Korean NPT violations -- and in the latter case we thought Pyongyang had already separated more than a bomb's worth of plutonium. Knowing this, bomb makers might figure that they could make lots of weapons before facing any severe reaction. And would they be wrong to expect that with bombs in hand, they would get more respect?
These points should wake us up to the dangers of the LWRs. These power reactors have their place, but they are too dangerous to be in countries with appetites for nuclear weapons and few other ways to acquire them. They don't belong in North Korea -- at least under the present closed regime -- and they don't belong in Iran until things there change, too. In upcoming talks with Russia and North Korea, we should spell out the dangers of LWR fuel. We also must take the dangers into account in considering future LWR deals and in reevaluating the safeguards system that applies to all of them.
It is too late to cancel the diplomatic ceremony around the pouring of the concrete for the LWRs in North Korea. But it would help if the diplomats there muted their enthusiasm and treated the occasion as one for reflection rather than celebration.