SEMEY, Kazakhstan -- Though much of Kazakhstan’s Cold War-era nuclear detritus -- left over from years of Soviet atomic tests -- was sealed in a mountain years ago, it theoretically could be removed and used for illicit weapons of mass destruction, according to experts.
The hope is, though, that any such move to bore inside well-sealed tunnels for deeply hidden material and attempt to chemically extract fissile material would be so impractical as to offer little temptation to would-be bad actors.
Theoretically it is possible to pull high-grade plutonium from tunnels inside the Central Asian nation’s Degelen Mountain, but in real terms it is basically “impossible,” Sergey Lukashenko, director of the Institute of Radiation Safety and Ecology at Kazakhstan’s National Nuclear Center, told a group of visiting U.S. journalists. Their travel was organized by the International Reporting Project.
Special “binding agents” used to seal the nuclear material have made it “very difficult to take it out,” said Sergei Berezin, the deputy director general of the National Nuclear Center, which oversees the former Soviet nuclear testing grounds.
He said it would be “cheaper to produce new plutonium from scratch” than to attempt to withdraw the nuclear material from Degelen in northeastern Kazakhstan, near the Russian border. The high cost of getting at the fissile material would make any extraction operation by clandestine scavengers financially unappealing, Berezin suggested.
Unbeknownst to many people, for years after the fall of the Soviet Union, there existed a very real danger that large chunks of high-grade plutonium leftover from nuclear weapons tests might be discovered in the tunnels of Degelen, collected and then sold on the black market to terrorists, according to an investigative report called “Plutonium Mountain” published last week by the Belfer Center for Science and International Affairs at Harvard University.
The danger was averted, thanks to a fruitful three-way cooperative arrangement between the United States, Russia and Kazakhstan -- along with some amount of luck. The detailed inner workings of that 17-year effort to secure the plutonium inside Degelen Mountain were revealed for the first time in the 40-page report. The public, though, got a taste of just how serious a proliferation danger existed in early 2011 when Wikileaks published U.S. State Department cables that discussed the project.
The three nations declared last fall that they successfully had secured almost all of the sensitive nuclear material at Degelen. Intergovernmental consultations are said to be ongoing for a separate project that would gather up a large amount of plutonium-contaminated soil from around the Semipalatinsk Test Site, which could be used to build a radiological “dirty bomb,” and place it inside the mountain structure.
The completed project to secure an unknown, but substantial, quantity of nuclear weapon-usable material inside Degelen was “one of the very few successful joint projects of the USA and Russia, where both parties can understand [each other] very well,” said Berezin. “We wish it was like that [for] every project,” he told reporters through a translator.
With the fall of the Soviet Union, much of the local Kazakhstani economy around the Semipalatinsk Test Site was devastated, leading a number of people to take up scavenging for copper wiring and other metals in Degelen Mountain that they could sell. The scrap metal was left behind by Soviet scientists and workers, who from 1961 to 1989 built up an elaborate tunnel infrastructure to support more than 220 underground tests, according to the Belfer Center report.
From 1993 to 1997, the United States carried out a $6 million effort to destroy the nuclear testing infrastructure at Degelen, sealing its 181 tunnels and 13 test shafts, says the report by Eben Harrell, an associate at the Belfer Center’s Project on Managing the Atom, and David Hoffman, a contributing editor at the Washington Post.
Per an agreement with Russia, the tunnels were closed without any U.S. officials exploring their interiors, so there was no full accounting of the nuclear-weapons-usable material there.
“The tunnel sealing had not dealt with the fissile materials the Soviets had left behind -- some of which were readily accessible if anyone got inside the tunnels, and some of which were in containers outside the tunnels,” reads the report.
The closure also did little to prevent enterprising local scavengers from using industrial equipment to drill through the seals and reenter the tunnels to resume searches for valuable metals. Gold-mining operations also were taking place in close vicinity of the site, according to the report.
It would take more than a decade before these remaining risks were addressed -- work that required new cooperation between Kazakhstan, Russia and the United States.
U.S. nuclear weapons scientist Siegfried Hecker began in 1997, after his retirement as director of Los Alamos National Laboratory, to focus much of his energies on convincing the U.S. government that there was still a serious proliferation risk at Degelen Mountain.
Not all of the Soviet Union’s nuclear tests and experiments inside and around Degelen resulted in the dispersal of the used fissile material. Some tests were duds that left behind whole chunks of undetonated highly enriched uranium or plutonium. Other experiments are thought to have left behind smaller pieces of high-purity plutonium and uranium material, the Belfer report states.
Some nuclear experiments took place outside of Degelen at nearby fields, where bore holes were dug to house the procedures. Other, smaller atomic experiments were conducted in "kolbas," which are special containment chambers. Some of the kolbas were sealed inside the mountain, but some of them lay outside the mountain in the open, according to the report.
“This material would be easily accessible to recover by a group interested in obtaining weapons materials for nuclear proliferation,” Hecker wrote in a 1998 letter to the U.S. embassy in Kazakhstan, summarizing the situation at Degelen, according to the Belfer report.
Subsequent fieldwork turned up enough accessible plutonium in just the kolbas and other more-compact and less-protected “end-boxes,” which housed atomic experiments with smaller explosive yields, to fuel more than 12 nuclear warheads, according to the report.
“Individuals could easily access the area and ‘mine’ the material without being detected,” Hecker wrote.
During one visit in 1998, “Hecker was shown one of the Semipalatinsk test tunnels which had been closed earlier in the decade by the U.S.-backed program. The front of the tunnel was plugged, but the scavengers -- looking for steel rails which had been laid in the tunnels -- broke in by drilling down from above, bypassing the plugs,” the report states.
By luck, it appears that no scavengers ever made off with any notable quantities of high-grade uranium or plutonium. But they are believed to have come extremely close to finding the material.
In two incidents, metal foragers broke into containment chambers used for nuclear experiments; however, there were no indications that any plutonium had been removed, according to the report authors. The Pulitzer Center on Crisis Reporting and the MacArthur Foundation sponsored their work.
For a time, efforts to secure Degelen Mountain were carried out semi-informally by U.S. scientists and some former Soviet counterparts who shed light on work done years before at Semipalatinsk. Kazakhstan supplied laborers to seal off the tunnels and close the bore holes.
In 2000, the United States, Russia and Kazakhstan held talks on heightening their mutual efforts to further secure the fissile material.
Washington agreed to finance the project, which ultimately cost $150 million. Russia provided information about suspected locations of fissile material. Kazakhstan arranged for project personnel to enter the nation and allowed the international work to take place.
Scientists devised different solutions for securing various pockets of fissile material, according to the Belfer report.
The nuclear material located inside the kolbas was secured against extraction by pumping a specialized concrete mixture containing iron into the containment chamber. The bore holes also were sealed.
“Now all of these tunnels are blocked -- and not only blocked; we [also] make a special physical [concrete] barrier,” said Lukashenko, the Institute of Radiation Safety and Ecology director.
Progress moved along in fits and starts after the turn of the century, with one pause attributed to a lapse in an umbrella agreement that governed Kazakhstan’s participation in the U.S. Cooperative Threat Reduction program.
At the 2010 Global Nuclear Security Summit in Washington, President Obama, then-Russian President Dmitry Medvedev and Kazakhstani President Nursultan Nazarbayev jointly agreed to wrap up work at Degelen by 2012.
This political deadline gave the project the final push it needed and, in October of last year, officials from the three nations gathered at Semipalatinsk to formally toast completion of the project.