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June 2, 2022
Deconstructed: North Korea's Nuclear Programs
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Paul Kerr

President George W. Bush has declared that he will only support an agreement with North Korea that contains measures to verify the complete and irreversible end of Pyongyang’s nuclear weapons programs. Yet, implementing such an agreement will be complicated by U.S. officials’ limited intelligence about these programs. North Korea’s closed society and strict control of information, along with an apparent paucity of relevant human intelligence, have forced U.S. officials to make intelligence assessments based on relatively limited information. In fact , these intelligence assessments have sometimes shifted over time without any new public evidence warranting the shift.

Any verification scheme resulting from a new agreement with North Korea will have to account for both its plutonium- and uranium-based nuclear programs. The following is a summary of the best publicly available information about Pyongyang’s nuclear programs.


Plutonium Programs

At least some of North Korea’s plutonium facilities are already known to the United States and have been subject to International Atomic Energy Agency (IAEA) monitoring under a 1994 agreement—the Agreed Framework—between the two countries.

Pre-1992 Nuclear Activities

The current North Korean nuclear crisis originated in 1992 when the IAEA uncovered evidence that North Korea had separated more plutonium from spent fuel generated by its five-megawatt nuclear reactor at Yongbyon than it had initially declared to the agency. In an attempt to determine how much plutonium North Korea had actually produced, the IAEA demanded “special inspections” in 1993 of two suspected nuclear-waste storage facilities that North Korea had not declared to the agency.

North Korea reacted to the IAEA request by announcing its intention to withdraw from the nuclear Nonproliferation Treaty (NPT), sparking a diplomatic crisis that was ultimately resolved in October 1994 when the United States and North Korea concluded the Agreed Framework. That agreement charged the IAEA with monitoring a freeze of North Korea’s nuclear facilities at Yongbyon as well as approximately 8,000 spent fuel rods. The agreement also mandated that the agency be allowed to finish its inspections after an international consortium had completed a “substantial portion” of the construction of two proliferation-resistant nuclear reactors promised to North Korea. The construction of the reactors, however, lagged far behind schedule prior to the project’s suspension at the beginning of December 2003. The IAEA has never been able to conduct full inspections of North Korea’s nuclear facilities. (See ACT, December 2003.)

U.S. intelligence assessments that North Korea has built one or two nuclear devices are believed to be based on estimates of the amount of spent fuel North Korea reprocessed prior to 1992 (approximately 12 kilograms, according to a reported CIA estimate).

Post-January 2003

Since ejecting IAEA inspectors in December 2002 and announcing its withdrawal from the NPT, North Korea has restarted the Yongbyon reactor, announced that it has completed reprocessing the spent fuel placed in storage under the Agreed Framework, and implied that it is using the plutonium to fabricate nuclear weapons. Scientists say that such an amount of spent fuel could yield enough fissile material for up to six nuclear weapons, depending on the efficiency of North Korean scientists and technicians.

Consequently, any verification scheme will have to determine how much of the spent fuel, if any, North Korea has reprocessed. Such an investigation would include both the area in which the spent fuel was stored and the reprocessing facility, as well as any hot cells that North Korea possesses. Hot cells are small, shielded rooms that can be used to reprocess small amounts of spent fuel. Inspectors will also need to take into account the possibility that North Korea has clandestine reprocessing facilities.

Additionally, inspectors will have to investigate the status of the five-megawatt reactor, including whether North Korea has reprocessed any spent fuel produced since restarting the reactor in February 2003. That reactor can produce fissile material sufficient for approximately one nuclear warhead per year, according to U.S. estimates.

Investigators will also need to assess the status of two larger, incomplete reactors whose construction was frozen under the Agreed Framework. North Korea has implied that it may resume construction of those reactors. Ambassador Robert Gallucci, who helped negotiate the 1994 agreement, estimated that these reactors could produce sufficient fissile material for approximately 30 nuclear weapons per year when finished. These reactors are, however, at least several years from completion.

Uranium Enrichment

North Korea denies U.S. charges that it has a gas centrifuge-based uranium-enrichment program. Little is known about this program, including the location of its related facilities. Clandestine centrifuge facilities are widely believed to be more difficult to detect than plutonium-based nuclear programs.

According to U.S. estimates, North Korea’s uranium-enrichment program appears to be significantly less advanced than its plutonium-based program. North Korea is believed to have procured components for a gas-centrifuge-based uranium-enrichment facility, but there is no publicly available evidence that it has integrated these components into a functioning system capable of producing uranium.

Public CIA assessments about the program have changed significantly during the past year. The CIA said in November 2002 that North Korea was “constructing a centrifuge facility” capable of producing “two or more nuclear weapons per year,” perhaps as soon as “mid-decade.” Assistant Secretary of State James Kelly told Congress in March 2003 that the facility could start producing fissile material in “months and not years.”

Subsequent CIA reports have been increasingly vague. For example, a November report covering the last half of 2002 says only that North Korea “had begun acquiring material and equipment for a centrifuge facility,” with the apparent “goal” of building a plant. Another November report covering the first half of 2003 says nothing about the program.