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North Korea: second nuclear test

Nuclear Monitor Issue: 
LAKA Foundation

On May 25 North Korea conducted a second underground nuclear test. History shows that – in contrast with import of uranium enrichment technology - there is nothing illegal about the acquisition of the weapons-grade plutonium by North Korea and its nuclear test. It’s an everlasting myth that underground nuclear blasts don’t cause any radioactive contamination. In fact they can just only conclusively proved by this phenomenon. The only way to stop nuclear testing is to stop and to prevent the rationale of deterrence by mediating conflicts.

The May 25 blast was up to 20 times more powerful than the first nuclear test on October 9, 2006. This first test was considered to have been relatively weak, about 1 kiloton, suggesting design problems. Pyongyang’s official Korean Central News Agency (KCNA) gave no details of the location of the latest test. However, South Korean officials said a tremor was detected around the north-eastern town of Kilju, near where the first test was conducted, close to the Russian border.

In a comment in The Times Dr. David Lowry, former director of the European Proliferation Information Centre, stated that Korea’s actions are not unlawful or illegal, though they are certainly against progressive security norms. In January 2003, North Korea didn’t illegally leave the Non-Proliferation Treaty (NPT), as under treaty Article X this is permitted. Lowry: “Among the grievances North Korea cited to justify departure from the NPT was continuous verbal aggression by a bellicose U.S., including dubbing North Korea a “rogue state,” and President Bush including North Korea with Iraq and Iran as part of the infamous Axis of Evil.”

Radioactive pollution
In order to calm down the public in Russia's Far East, the Russian media reported that a team of meteorologists hasn't detected an increase in radiation levels in the air. However, an anonymous U.S. official said that tests for radioactivity in air samples from the region were still underway. After the 2006 nuclear test, it took a U.S. airplane less than a week to detect radioactive material in air over the East Sea. Though the seismology readings are consistent with an atomic explosion, an initial round of analysis did not confirm that Pyongyang fired a second atomic bomb. Another defense source declared to the South Korean press agency Yonhap that South Korea is checking air samples for radioactive material at the military facility in Dongducheon, 40 km north of Seoul and only 15 km from the border, and where the U.S. Forces has a large portion of its troops stationed. They operate jointly with other centers across South Korea to confirm the North Korean announcement of a nuclear test, the source said.

Virtually all underground tests leak a fraction of their radioactive noble gases after the blast. These gases can be detected hundreds of meters high at distances hundreds or thousands of kilometers away. This is where the anonymous official was referring to. South Korea, Japan and the U.S. are currently sampling the air downwind of the North Korean test site and trying to detect traces of radioactive xenon, a common tracer of a nuclear explosion. About 8 percent of the elements created in the fission explosion comprise radioactive noble gases of krypton and xenon. These radioactive gases can damage our genetic material and many many of them decay into solid radioactive particles that are known as deadly substances. 

History of North Korea’s nuclear program
North Korea’s nuclear program started in the 1950s with conducting research on radioactive isotopes for multiple applications at the Academy of Sciences. The Yongbyon nuclear energy research complex was built in the early 1960s. After completion the Soviet Union provided the IRT-2000 Nuclear Research Reactor at the site in 1965. The small research reactor first went critical in August 1965, but did not become fully operational until 1967 after two years of testing. The IRT-2000 was originally 2MW(th), but North Korea expanded its capacity to 4MW(th) in 1974, and to 8MW(th) in 1987. Pyongyang subsequently expanded the complex and built a number of new facilities. The Yongbyon facility houses thousands of scientists and researchers, many of whom studied nuclear technology in the Soviet Union, China and Pakistan. The military runs the nuclear weapons program along with the intelligence service — under the direct supervision of President Kim Jong-Il.

The Yongbyon nuclear energy research complex includes a large plutonium reprocessing plant as known as the Radiochemistry Laboratory. This facility is a six-story building, approximately 180m in length, 20m in width, and about the size of two football fields. The primary function of the installation is to reprocess spent nuclear fuel. One assumes the construction began in 1985, and by 1992 it had been completed. North Korea signed the NPT in 1985 but did not submit to IAEA inspections until May 1992. In May 1992 North Korea declared to the IAEA that this facility was for training nuclear specialists in separating plutonium, and for handling nuclear waste. However, during IAEA inspections in 1992, the IAEA concluded that it was a reprocessing facility. In 1993, IAEA inspectors discovered that North Korea was preparing to install a second reprocessing line in the building. At that time, inspectors estimated that about 70 percent of the facility’s internal equipment had been installed.

Experimental Reactor
The plutonium North Korea separated in the Radiochemistry Laboratory for building their nuclear weapons was probably mainly from the spent nuclear fuel of its 5MW(e) Experimental Reactor. This is a graphite-moderated, gas-cooled reactor with a thermal power range of 20-25MW. In his comment in The Times Lowry reminds to a long forgotten written Parliamentary answer in the House of Commons by Douglas Hogg, when he was a junior foreign office minister 15 years ago. Responding to Llew Smith, then a backbench Labour MP with strong anti-nuclear leanings “We do not know whether North Korea has drawn on plans of British reactors in the production of its own reactors. North Korea possesses a graphite moderated reactor which, while much smaller, has generic similarities to the reactors operated by British Nuclear Fuels plc.” He then added: “However, design information of these British reactors is not classified and has appeared in technical journals.” A few months earlier, Hogg, responding to another Smith question asking whether the foreign office had been requested by the IAEA to provide details of the Magnox nuclear plant design from which the North Koreans developed its nuclear reactor design for the plant currently part of the nuclear inspection effort of the special IAEA safeguards inspection team presently in North Korea, revealed “Information has been provided to the IAEA on Magnox reactor design to allow it to validate a computer program used for reactor physics calculations. Such calculations can be applied in the safeguarding of any graphite moderated reactor.” This Magnox reactor design was the one used at Calder Hall at Sellafield to produce military plutonium for the U.K. nuclear weapons program […].”

Construction of the Korean Calder Hall clone reactor began in either 1979 or 1980, and was reportedly under construction by at least July 1980. The reactor is fueled by natural uranium, which is abundant in North Korea. Another advantage by using this reactor design is the use of carbon dioxide in the cooling system, which means that it doesn’t need heavy water. In addition, the reactor uses graphite as a moderator. Graphite is also available in North Korea. The problem with this type of reactor is that it is difficult to store the spent fuel for an extended period - the fuel cladding is magnesium, which breaks down when exposed to water or moisture – turned out to be an advantage for North Korea. There isn’t necessarily a suspicion for military purposes when the spent fuel is reprocessed, because this activity is a necessity in this case. The reactor went critical on August 14, 1985 and operational in 1986. According to North Korea the reactor was operated between 1986 and 1994. According to data presented on the website of the Nuclear Threat Initiative (NTI) the reactor was shut down for 71 days in 1989, about 30 days in 1990, and about 50 days in 1991. These periods could have been used to discharge the spent fuel. The reactor was not being monitored by the IAEA because North Korea did not ratify a safeguards agreement until April 1992.

Plutonium stocks in the 1990s
The amount of plutonium that could have been taken from the Experimental Reactor depends upon the operational history of the reactor, the reprocessing technology, and the measure in which North Korea exploited the opportunities provided by shutdowns of the reactor in 1989, 1990 and 1991. According to IAEA inspectors North Korea almost certainly reprocessed plutonium in all three years. It is widely assumed that about 4 kg of plutonium has been reprocessed from the IRT-2000 Nuclear Research Reactor and that the upper bound for the amount of plutonium that could have been extracted from the Experimental Reactor is approximately 6.9 to 10.7 kg. These amounts, calculated by David Albright are widely accepted by analysts. Enough weapon-grade plutonium for two bombs. Sources within Japanese and South Korean intelligence services claim North Korea may have extracted more plutonium during reactor slowdowns in 1990 and 1991, with a total amount of 24 kg of plutonium. In 1993 the German weekly magazine Stern cited a Russian counterintelligence report claiming that North Korea had bought 56 kg of Russian plutonium on the black market.

IAEA safeguards inspections
In April 1992, after inspection of the Experimental Reactor and other nuclear facilities in Yongbyon, the IAEA discovered discrepancies in North Korea’s initial declaration. This led to special ad hoc inspections. In June 1993, Pyongyang began bilateral negotiations with Washington to resolve the impasse. North Korea allowed the batteries and film for cameras to be replaced, but not the return of IAEA inspectors to complete the inspections that began in May 1992. In May and June 1994, North Korean technicians, without the supervision of IAEA inspectors, once again discharged the reactor’s spent fuel rods and placed them in the cooling pond. This action nearly led to a military confrontation with the United States, before former President Jimmy Carter’s trip to Pyongyang defused the crisis. Carter’s trip encouraged Kim Il Sung to accept some guidelines that resulted in the negotiation and conclusion of the Agreed Framework in October 1994.

Nuclear trade with Khan
With the abandonment of its plutonium program after the Agreed Framework, U.S. officials claimed North Korea began a uranium enrichment program. Around 1997, according to U.S. intelligence officials, Pakistan, through Abdul Qadeer Khan, supplied key technology and information to North Korea in exchange for missile technology. From Pakistan, ultracentrifuge technology, knowledge and material, were exported to among others North Korea. A mixture of legal and illegal transactions, involving businessmen from all over the world as well as individuals in the higher circles of the military and political elite in Pakistan allowed nuclear proliferation to proceed much faster than even those familiar with the issue expected. In the 1970s Khan obtained the most modern blueprint from the drawing board of Urenco’s ultracentrifuge technology in the Netherlands. President Musharaf acknowledged in 2005 that Khan had provided centrifuges and their designs to North Korea. Some evidence points to the existence of this program as early as 1987. This program apparently received new life in 1997 when Pakistan, strapped for cash by U.S. sanctions, began paying for its North Korean missile imports with uranium enrichment technology. In a written statement - that was mentioned in relation to Khan’s public confession of having leaked nuclear technology on 4 February 2004 - Khan himself is said to have confessed to selling nuclear technology to Iran, Libya and North Korea.

A December 2001 U.S. National Intelligence Council report ascertained that in the mid-1990s, North Korea had produced one, possibly two, nuclear weapons. In December 2002, Pyongyang lifted the freeze on its plutonium-based nuclear weapons program and expelled IAEA inspectors. On 10 January 2003, North Korea declared its withdrawal from the NPT and on 10 February 2005, North Korea announced that it had manufactured nuclear weapons.

Current plutonium stocks
In May 2008 the U.S. received North Korean Plutonium Program documents. North Korea delivered 18,000 pages of documents describing the nation’s plutonium production program to a senior U.S. State Department official. Included in the records is information on the state’s efforts in 1990, 2003 and 2005 to reprocess plutonium for nuclear weapons. The records should help to clarify the amount of plutonium produced by Pyongyang. Officials there have apparently placed the stockpile at around 30 kg, while U.S. officials believe the actual amount could be closer to 50 kg. The receipt of the documents took place during talks that were held aiming at breaking the deadlock over the October 2007 six-nation agreement under which North Korea would receive economic, security and diplomatic benefits in exchange for giving up its nuclear sector.

Rationale of nuclear tests and necessity of nuclear disarmament
In line with the statements made by Dr. David Lowry, David Krieger - president of the Nuclear Age Peace Foundation – notes that the rationale for virtually all nuclear tests by all states has been to bolster a country’s nuclear deterrent for the purpose of self-defense. The five permanent members of the U.N. Security Council, all nuclear powers, have tested nuclear weapons in total more than 2,000 times. The U.S. alone has tested over 1,000 times. That means that North Korea, which has conducted two nuclear tests, has tested one thousandth the number of times as the five recognized nuclear weapons states have tested and one five-hundredth the number of times the US has tested. Krieger adds to these clarifying comparisons: “It is, of course, dead wrong that deterrence provides a country with protection. In fact, it may lead to a country being attacked by nuclear arms.” U.S. President Barack Obama promised to place nuclear nonproliferation and nuclear disarmament high on his administration's agenda. He seems to understand the threat of an increasing nuclear deterrence on the globe. Hopefully, these first steps of the Obama administration will have major follow-ups.

Sources: The Moscow Times, 27 May 2009 / AFP, 29 May 2009 / Yonhap. 26 May 2009 /
‘Nuclear explosions conducted underground are definitely not safe’at / / / Nuclear Monitor, 15 May 2008 / Korea’s actions are not unlawful, The Times, 29 May 2009 / A.Q. Khan, Urenco and the proliferation of nuclear weapons technology at /

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