h minimal foreign equipment procured. When the joint statement on the Denuclearization of the Korean Peninsula was concluded in December 1991, all three facilities had been fully operational for a number of years, with two additional (50 MWe and 200 MWe) graphite moderated gas cooled reactors under construction.
The Enrichment Route
North Korea’s closed society and isolationist position has made it immensely difficult to accurately gauge its nuclear activities. Pyongyang has gone to great lengths to hide much of its nuclear program, including its enrichment route. Nevertheless, there have been indications, including procurement related evidence, that point in the direction that North Korea has been actively pursuing enrichment since the mid-1990s, with likely exploratory attempts made up to a decade earlier.
It is clear that North Korea received a key boost in its uranium enrichment capability from Pakistan through the A.Q. Khan network. Deliveries of P-1 and P-2 centrifuges, special oils, and other equipment from Pakistan to North Korea in the late 1990s were acknowledged by former Pakistani President General P. Musharraf in his memoirs, “In the Line of Fire.” President Musharraf also wrote that, separately, North Korean engineers were provided training at A.Q. Khan’s Research Laboratories in Kahuta under the auspices of a government-to-government deal on missile technology that had been established in 1994. In all likelihood, North Korea also received the blue prints for centrifuges and other related process equipment from the Khan network during that period of time.
In the late 1980s, North Korea acquired vacuum equipment from a German company. While such equipment was primarily meant for North Korea’s fuel fabrication plant then under construction, some of the vacuum pumps could have been used for enrichment experiments. But additional attempts made in 2002 to again acquire vacuum technology after the completion of the fuel fabrication plant strongly pointed to its use for enrichment purposes. Evidence of North Korea’s procurement activities in the late 1990s to the early 2000s showed its objective to achieve industrial or semi-industrial scale enrichment capacity, based on a more efficient Pakistani P-2 centrifuge design. In 1997, an attempt was made to acquire large amounts of maraging steel suitable for manufacturing centrifuges. In 2002/2003, North Korea successfully procured large quantities of high strength aluminum from Russia and the United Kingdom, another requirement in making centrifuges. A simple tally of the amounts and types of equipment and material sought by North Korea suggests plans to develop a 5000-centrifuge strong enrichment capacity. This appears consistent with a separate earlier enrichment offer A. Q. Khan had made to Libya.
For North Korea to have embarked on procuring equipment and materials meant for a (semi)industrial scale enrichment facility, it is highly likely that the known Uranium Enrichment Workshop (UEW) at Yongbyon, which in reality approximates a full sized facility, is not the only one that exists. More workshops would have been needed to serve as test beds for pilot cascades of P-1 and P-2 centrifuges prior to (semi)industrial scale enrichment operations. While we have signs of North Korea’s enrichment goals, the final picture remains unclear given that the actual amount of items procured remains unknown. This problem is compounded by the fact that the North Koreans have and are continuing to source nuclear material and equipment from several parties. Moreover, there remains a high degree of uncertainty concerning the level of North Korea’s enrichment technology development.
In April 2009, after expelling IAEA inspectors, North Korea publicly announced for the first time that it was proceeding with its own enrichment program. To reinforce its intentions, North Korea followed up with a letter to the UN Security Council on September 3 to confirm that it was embarking on an enrichment phase. In November 2010, the North Koreans unveiled to Siegfried Hecker, a pre-eminent nuclear e