| Yongbyon Nuclear Scientific Research Center | |
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The 5 MWe experimental reactor |
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| Korean name | |
| Chosŏn'gŭl | 녕변핵시설 |
| Hancha | 寧邊核施設 |
| McCune–Reischauer | Nyŏngbyŏn haeksisŏl |
| Revised Romanization | Nyeongbyeon haeksiseol |
The Yongbyon Nuclear Scientific Research Center[1] is North Korea's major nuclear facility, operating its first nuclear reactors. It is located in the county of Nyŏngbyŏn in North Pyongan province, about 90 km north of Pyongyang. The center produced the fissile material for North Korea's nuclear weapon tests in 2006 and 2009, and since 2009 is developing indigenous light water reactor nuclear power station technology.
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The major installations include all aspects of a Magnox nuclear reactor fuel cycle, based on the use of natural uranium fuel:
Magnox spent fuel is not designed for long-term storage as both the casing and uranium metal core react with water, it is designed to be reprocessed within a few years of removal from a reactor. As a carbon dioxide cooled, graphite moderated Magnox reactor does not require difficult-to-produce enriched uranium fuel or heavy water moderator it is an attractive choice for a wholly indigenous nuclear reactor development.
The Magnox facilities were disabled in 2007 in accord with the six-party talks agreement, but following the breakdown of that agreement were partially re-enabled in 2009 to reprocess existing stocks of spent fuel.
The center also has an IRT-2000 pool-type research reactor, supplied by the Soviet Union in 1963, operational since 1965.[2] The reactor fuel is IRT-2M type assemblies of 36% and 80% highly enriched uranium.[3][4] As the center has not received fresh fuel since Soviet times, this reactor is now only run occasionally to produce Iodine-131 for thyroid cancer radiation therapy.[5]
In 2009 North Korea announced its intention to build an indigenous experimental light water reactor and the uranium enrichment technology to provide its nuclear fuel.[6] In 2010 a 2,000 gas centrifuge uranium enrichment plant to produce low enriched uranium (LEU) fuel began operating, and construction started on the experimental 25 to 30 MWe light water reactor, with a target operation date for the reactor of 2012.[7] In November 2011, satellite imagery indicated that the reactor construction is progressing rapidly.[8]
Construction of the 5 MWe experimental reactor began in 1980, and the reactor first went critical in August 1985. This reactor was an initial small technology proving reactor for a following development program of larger Magnox reactors. It operated intermittently until 1994 when it was shut down in accordance with the U.S.-North Korea Agreed Framework. Following the breakdown of the Agreed Framework in 2002, operation restarted in February 2003, creating plutonium within its fuel load at a rate of about 6 kg per year.[9] The reactor fuel was replaced between April and June 2005. The spent nuclear fuel has been reprocessed with an estimated yield of about 24 to 42 kg of plutonium metal,[9] some of which was used for the nuclear weapons involved in the 2006 and 2009 North Korean nuclear tests.[10]
Yongbyon is also the site of a 50 MWe Magnox prototype power reactor, but construction was halted in 1994 about a year from completion in accord with the Agreed Framework, and by 2004 the structures and pipework had deteriorated badly.[11] This construction was being dismantled in 2010.[7]
Another 200 MWe Magnox full-scale power reactor was being constructed at Taechon, 20 km north-west of Yongbyon, () until construction was also halted in 1994 in accord with the Agreed Framework. By 2005 reconstruction of this reactor was uneconomic.
The reactor designs were based on declassified information about the British Magnox design at Calder Hall and elsewhere, and the spent fuel reprocessing plant on the multi-national European Company for the Chemical Processing of Irradiated Fuels (EUROCHEMIC) plant at Mol-Dessel in Belgium.[9]
On Tuesday 13 February 2007, an agreement was reached at the Six party talks that North Korea will shut down and seal the Magnox nuclear reactor and associated facilities and invite back International Atomic Energy Agency personnel to conduct all necessary monitoring and verifications.[12] In return for this North Korea will receive emergency energy assistance from the other 5 parties in the form of 50,000 tons of heavy fuel oil.
International Atomic Energy Agency (IAEA) inspectors arrived at the site on June 28 to discuss verification and monitoring arrangements for the shutdown.[13] This had been delayed from April due to a dispute with the United States over Banco Delta Asia.[14] On June 3 an anonymous South Korean government official indicated that the shutdown may start following the first oil shipment later in the month.[15] On July 14, Sean McCormack stated that North Korea had told the US that the reactor had been shut down. He added that the US welcomed the news, and was awaiting verification from the IAEA team.[16] The next day, IAEA chief Mohamed ElBaradei announced the UN's confirmation that the reactor had been shut down.[17] On 18 July 2007, the IAEA confirmed that all five nuclear facilities at Yongbyon had been shut down.[18]
In his Introductory Statement to the IAEA Board of Governors on 2008-03-03, the Director General stated that he could not provide an update on the disabling of the facilities, as it was not undertaken by the IAEA. All fuel rods from the 5 MWe Experimental Nuclear Power Plant and nuclear material generated by the disabling of the Nuclear Fuel Fabrication Plant were under IAEA containment and surveillance.[19]
On Friday 27 June 2008, North Korea destroyed the most visible symbol of its nuclear weapons program - the cooling tower at its main atomic reactor in the complex. The implosion was witnessed by a number of international journalists and diplomats.[20]
The demolition of the 60-foot (18 m)-tall cooling tower, which carried off waste heat to the atmosphere, is a response to U.S. concessions after the North delivered a declaration of its nuclear programs to be dismantled. The United States paid the US$2.5 million demolition fee.
During 2008 tensions resurfaced between North Korea and the U.S. due to disagreements over the six-party talks disarmament process. On October 8, 2008, IAEA inspectors were forbidden by the North Korean government to conduct further inspections of the site. However two days later the U.S. removed North Korea from the U.S. State Sponsors of Terrorism list and the Yongbyon deactivation process resumed.[21]
According to the state-run North Korean news agency KCNA website, the DPRK resumed the processing of fuel rods to recover plutonium at Yongbyon on April 25, 2009 in response to the UN's condemnation of its recent rocket launch. This material supplemented that used for nuclear weapons testing.[22]
The DPRK had previously carried out an initial nuclear test on 9 October 2006. This first North Korean nuclear test on 9 October 2006 was detected immediately by the United Nation’s Comprehensive Nuclear-Test-Ban Treaty Organization seismic stations, despite its small yield; the findings were subsequently corroborated by the detection of radioactive noble gases from the test.[23] As a result the United Nations Security Council unanimously adopted Resolution 1718 condemning the test and demanding that the DPRK give up nuclear weapons. The Democratic People's Republic of Korea carried out a subsequent underground nuclear test on 25 May 2009.[24] Sig Hecker, former director of Los Alamos National Laboratory, indicated that the DPRK program holds the potential for producing about six to eight bombs. Their initial weapons produced a limited-success nuclear test on 9 October 2006, with a yield estimated at between 0.3 to 1.0 kiloton.[25]
The DPRK’s Korean Central News Agency announced that the 25 May 2009 test had demonstrated an increase in explosive power over its low-yield 2006 nuclear test.[26] Russia's Defense Ministry provided a preliminary estimate that its yield was 10 to 20 kilotons - comparable to the bombs dropped by the US on the Japanese cities of Hiroshima and Nagasaki in August 1945.[27] However Park, writing in the Bulletin of the Atomic Scientists, stated: "The reported estimates of Richter magnitude spread from 4.5-5, and the standard conversions to explosive yield suggest a yield of 2-6 kiloton-equivalents of TNT. Most of the latest Richter magnitude estimates have come in the low half of the 4.5-5 range, so it seems likely that the yield was 4 kilotons or smaller." From this he concluded, that the May 2009 explosion's yield "was still far short of the expected yield of a crude Hiroshima-type bomb. More than likely this means North Korea tried and failed to get a simple plutonium bomb to detonate correctly."[28]
On November 12, 2010, the facility was visited by Siegfried Hecker who prepared an updated report demonstrating the unexpectedly advanced state of the plant.[29] Among the surprising findings were the presence of 2,000 recently completed high-speed centrifuges that are able to produce enriched uranium.[30]
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