The Nuclear Time Bomb

Since the end of the cold war, the United Nations has logged more than 800 incidents in which radioactive material has gone missing, often from poorly guarded sites. Who is taking it - and should we be worried? Julian Borger investigates.

Bulgarian Greenpeace activiststs march dressed in anti-radiation suits on the streets of the capital Sofia. Photograph: Vassil Donev/EPA

A little before dawn on a recent summer morning, a convoy of three large blue lorries, a handful of police cars and a bus rumbled along the dual carriageway heading north out of the Bulgarian capital, Sofia. Even if it had not been so early, the motorcade would probably not have drawn much attention. The lorries were unmarked, the bus carrying a few sleepy policemen was old and scruffy, while the lumbering shipment was big and slow enough to explain the escort and its flashing blue lights.

But for Bulgaria, and indirectly for the rest of us, the convoy's progress marked an important transition - the departure of the country's last remaining stockpile of High Enriched Uranium (HEU), the stuff of which nuclear bombs are made. It took two years of talks and preparatory work before the highly radioactive material - just over 6kg of spent fuel from a defunct research reactor - was fished out of the storage pools in which it had lain unused and largely forgotten for nearly 20 years. It was sealed in steel casks - custom-made by ...koda, the Czech car manufacturer - and lowered into the three anonymous blue trucks.

Over the course of the morning of July 5, the convoy made its way over the mountains and down to the banks of the river Danube, where the containers were winched into a long, black barge bound for Ukraine. Ten days and a rail journey later, the HEU arrived in Russia, whence it had come nearly half a century earlier as a gift. In Chelyabinsk, just east of the Urals, it is to be reprocessed or blended down. I was permitted to witness its secret journey on condition that nothing was printed until the shipment reached its destination, and this small but massively lethal fragment of the cold war was made safe.

The operation was the latest in a series - part of an accelerating scramble to clean up the scattered legacy of nuclear profligacy. In the 50s and 60s, the US and Soviet Union exported HEU-powered nuclear reactors to their allies for power generation and experimentation. When the cold war finally came to an end, deals were done on dismantling the redundant weapons in the former Soviet republics. Under a programme called Megatons To Megawatts, one tenth of America's electricity is generated from uranium from thousands of former Soviet warheads. The Russians blend down HEU in the warheads to Low Enriched Uranium (LEU), which cannot be used in bombs; the Americans transport it to nuclear power stations back home.

However, that still left thousands of kilograms of weapons-grade material, mostly HEU, in civilian reactors at power stations and universities around the world, some with no more security than a watchman and a padlock.

As the logic of deterrence and mutually assured destruction recedes from the collective memory to be supplanted by the fears evoked by the September 11 attacks, nuclear terrorism has emerged as the number one threat to western security. The suicidal extremist driving a crude nuclear device into the centre of a major city is now the ultimate nightmare. George Bush and Tony Blair went to war in Iraq with the ostensible aim of preventing Saddam's assumed nuclear stockpile falling into the hands of al-Qaida jihadists. Barack Obama has called nuclear terrorism "the greatest danger we face".

The gap between rhetoric and effective action, however, is startling. The US has so far spent $648bn on the war in Iraq to eliminate a threat that never existed. The amount spent on removing fissile material from countries that actually do have the ingredients for a nuclear device has been paltry by comparison. The Global Threat Reduction Initiative (GTRI), launched in 2004 after previous efforts at eliminating the world's civilian stocks of fissile material had proved ineffectual, has an annual US budget of about $150m, or roughly what the US military spends in eight hours in Iraq. Britain allocates a respectable £36.5m a year to the programme, most of it on helping to secure nuclear sites in the former Soviet Union, but that still pales in comparison to the £1.7bn cost last year of keeping troops in Iraq.

There is no question that the threat of nuclear terrorism is real. As long ago as 1998, Osama bin Laden declared it was a religious duty to acquire nuclear weapons "to terrorise the enemies of God". Just days before the September 11 attacks in 2001, the al-Qaida leader met a Pakistani delegation, including two retired nuclear scientists, in Kandahar. According to accounts of that meeting, Bin Laden expressed keen interest in how to build a bomb and was told it was technically quite simple - acquiring the fissile material was the main obstacle.

Al-Qaida has spent years trying to overcome that problem. Western intelligence officials believe the organisation was cheated several times by middlemen claiming to have weapons-grade material for sale. An al-Qaida defector, Jamal Ahmed al-Fadl, has described helping Bin Laden clinch a deal in Sudan, his home country: Bin Laden paid $1.5m for a 30-inch cylinder supposedly containing South African uranium. The cylinder is widely believed to have been a fake.

Ivan Ivanov, a Bulgarian businessman working for a Dubai-based building contractor, claims to have met Bin Laden in Pakistan in April 2001, and to have been approached the day after the meeting by an al-Qaida scientist who proposed a scheme for buying Bulgarian nuclear material. Ivanov says he turned down the deal, but Bulgaria has remained a source of concern for anyone worried about proliferation. The country's post-Soviet nuclear industry has been hit by one safety scandal after another, and the EU has taken the unusual step of cutting off funds because of the hold that corruption and organised crime have on the country's economy.

The removal of Bulgaria's HEU last month was therefore more than a technicality. It represented the elimination of a significant threat. Officials at Sofia's Institute for Nuclear Research and Nuclear Energy, where the spent fuel had been stored since its reactor was shut down in 1989, claimed security had been beefed up in recent years, but the Institute was clearly suffering from years of neglect. Feral dogs chased each other through the bushes in the grounds around the reactor.

The removal operation was overseen by a two-man American team, who represent the business end of the Global Threat Reduction Initiative. Their job is to fly around the world trying to persuade governments that it is in their long-term interests to part with their stocks of fissile material.

The US duo are both immigrants. Andrew Bieniawski, a 41-year-old from South Africa, is in charge of the programme at the National Nuclear Security Administration (NNSA), the part of the US department of energy that is responsible for looking after the US nuclear arsenal, making sure the bombs still work and do not blow up unexpectedly. His deputy, Igor Bolshinsky, a former mine technician from the Ukrainian coal city of Donetsk, has responsibility for repatriating the Soviet-origin material and does most of the travelling and persuading - "Schmoozing for world peace," as Bolshinsky put it.

"This is what keeps us on the road 70% of the time," he said. "We see different reactors in different conditions, and we know this removal has to be done very fast. We don't want to give more time to people who are preparing to steal this material."

In Sofia, Bolshinsky had been in fine form, cajoling, joking and flattering Bulgarian officials in a mix of Russian and English. He was consequently stunned on the designated day of the uranium's departure when Bulgarian security - somewhat prickly over the arrival of this ebullient American employee in the nation's inner nuclear sanctum - ordered the uranium convoy to leave the institute an hour earlier than agreed, without bothering to tell Bolshinsky.

In the past few years, Bolshinsky has overseen uranium removals from Libya to Vietnam, and has been tailed in the course of his duties by some of the world's most persistent secret policemen, but this stunt stretched his sense of humour to breaking point. "Not good, not good at all," he said emphatically when he turned up at the reactor at dawn to find the car park empty. He jumped into a car for a high-speed chase along a Bulgarian motorway, in pursuit of the missing uranium casks.

He finally caught up with the convoy about 32km north of Sofia, parked on the hard shoulder of the motorway. Ivan Gorinov, the head of "physical protection" at Bulgaria's Nuclear Regulatory Agency who appeared to have taken the decision to leave early, was unapologetic. "I don't care about the American taxpayer," Gorinov said defiantly, and a touch sulkily, when he was reminded that the exercise had been US-funded. Nor did he hide his lack of enthusiasm for the presence of journalists, suggesting that we might prefer to see a wet T-shirt competition underway in the nearby town of Kozloduy than observe the casks being loaded on to the giant barge.

Gorinov said later he would have been less nervous if the HEU shipment had gone by rail, but the necessary transit agreements would have taken too long to negotiate. It had been decided to take the quicker but riskier option of moving the uranium casks about 180km to the Danube by road, where it was theoretically vulnerable to ambush or protests.

"That was a big challenge, from the security point of view, and from the point of view of keeping it secret," Gorinov said, "but we had a constant exchange of information with the Bulgarian security services." A chain-smoker, he began to relax only when technicians in white coats and caps lowered the blue containers into the belly of the 86m barge and slid its long lid over them. "It looks just like any other barge - business as usual on the Danube," he declared triumphantly.

As the barge moved off downstream, heading towards Ukraine and a rendezvous with a Russian train, Bulgaria became officially free of HEU.

There are two kinds of nuclear bomb. Modern warheads involve an implosion device, in which the fissile material, normally plutonium, is violently compressed by shaped charges until it reaches critical mass, and the process of nuclear fission becomes self-sustaining. This is an extremely hard trick to pull off reliably, and is the province of sophisticated state programmes. However, there is a much cruder form of bomb, which achieves critical mass by firing one chunk of HEU at another. A "gun-type" bomb such as this, Little Boy, was dropped on Hiroshima. As the apartheid government in South Africa discovered, it can be developed by a relatively small team with some basic engineering skills. It is the sort of bomb a terrorist organisation would build. Plutonium is useless for such a device. It requires HEU, which happens to be far more plentiful and much less well guarded.

Under the GTRI, a total of 610kg of HEU fuel (both spent and fresh) has now been returned to Russia from countries including Serbia, Romania, Libya, Uzbekistan, Poland, Germany, the Czech Republic, Latvia and Vietnam. More than a third of those shipments took place in 2007, as the urgency underlying the programme has increased. US-made HEU has meanwhile been repatriated from Latin America, Europe and south-east Asia. In fact, at about the same time the uranium convoy was leaving Sofia, secret shipments of HEU and plutonium were on the way to the US from Japan, Sweden, Germany and Denmark. More than 50 HEU reactors around the world have been converted to use LEU. Four reactors have been closed down altogether.

Hungary and Kazakhstan are next on Bieniawski and Bolshinsky's visiting list, after which virtually all the fresh HEU fuel being stored at civilian sites around the world will have been dealt with. And almost all the Soviet-origin spent HEU, which can still contain high concentrations of weapons-grade material, is due to be removed from civilian sites around the world by 2010. Bieniawski said every day counts. "We are very concerned about this material. We take this threat to be very real. The information that we have lets us know we have to act as aggressively as possible to remove this material," he said.

The programme does not include military stockpiles, which are usually better guarded and are part of a different scheme, nor does it cover "gap" HEU fuel, made in neither the US nor the Soviet Union, but in countries such as South Africa that ran their own nuclear programmes. Ukraine and Belarus are also reluctant to give up all their HEU.

There is another, even more troubling, question hanging over Bieniawski and Bolshinsky's work: could their efforts already be too late? They are, in effect, running a race blindfold. They do not know if their adversaries - the terrorist groups, smugglers and bent officials with whom they work - are behind them, breathing down their necks, or ahead of them, or even whether they have already crossed the finishing line. What is beyond doubt is that they are in the race - and their footprints are all around.

Since the end of the cold war, the UN's nuclear watchdog, the International Atomic Energy Agency (IAEA), has logged more than 800 incidents in which radioactive material has gone missing or been seized from smugglers. Eighteen of those cases involved weapons-grade material, HEU or plutonium, mostly of Soviet origin. Another seven cases of weapons-grade theft or contraband have yet to be confirmed by the IAEA, but are considered well-founded.

In a recent example, a Russian fish trader and occasional smuggler named Oleg Khinsagov was arrested in Georgia in early 2006. He had about 100g of weapons-grade HEU in his leather jacket, wrapped in a plastic bag, and was under the impression he was about to sell his sample to a Muslim from a "serious organisation" on the market for fissile material. Khinsagov told his customer there were two more kilograms available. The would-be buyer turned out to be a Georgian government agent, and Khinsagov is now sitting in prison in Tbilisi, apparently too terrified of his Russian contacts to name them.

At a time when long-standing Russian-Georgian tensions have exploded into conflict, Moscow has been unhelpful in the extreme, implausibly claiming that it is impossible to tell where Khinsagov's HEU came from. Coincidentally or not, an estimated 2kg of HEU went missing when a top-secret former Soviet nuclear laboratory in the Georgian region of Abkhazia fell to Russian-backed separatists in 1993. It simply disappeared into the chaotic underworld of the Caucasus where organised crime thrives on national rivalries, and has not been seen since.

Last November, on the other side of the world, two groups of armed men broke into the emergency control centre at South Africa's supposedly high-security Pelindaba nuclear facility, where hundreds of kilograms of HEU are stored - they stumbled on a senior security official who was not supposed to have been there but was keeping his girlfriend company. The intruders shot him and fled.

In formal testimony to the IAEA, the South African government admitted the attackers were "technically sophisticated" and had "prior knowledge of the electronic security systems". On the other hand, they insisted the site's fissile material had not been in danger and that only a computer had been taken. There have been no arrests so far.

Most of the nuclear thefts located by the IAEA to date have involved small quantities of HEU, far short of the 55kg necessary to build a gun-type bomb, but no one knows how much more has disappeared unnoticed. Matthew Bunn, a proliferation expert at Harvard, has estimated the risk of a nuclear attack on the US in the next decade to be 29%. He was once asked by an investment bank to carry out a similar exercise for London. He will not say what he told the bank, revealing only that he estimated a smaller risk than his US estimate, but still "a real number".

James Acton, a nuclear proliferation expert at King's College London, said, "Even if you think that there is a one per cent, or half per cent, chance of there being such a catastrophic event, it's probably worth taking a lot more precautions than we are at the moment."

A terrorist group could make do with much less than the 55kg of HEU necessary to achieve critical mass and detonate whatever it had managed to steal or buy on the black market in the form of a "dirty bomb". Acton said radioactive material could also be sprayed like an aerosol across a wide urban expanse, in a stealth attack that could pass unnoticed until it was too late.

"If people insist on the same standards [for radioactivity] we have now, we would have to give up large areas of the city. People would ultimately have to get used to the risk of going back to a slightly contaminated part of London," Acton said. It would be so easy to perform and so devastating in its effects, he added: "I really don't know why an attack hasn't happened already."

Dhiren Barot, a north London al-Qaida member arrested in 2004 on terrorism charges, had been planning a dirty bomb attack using tiny radioactive particles found in home smoke alarms, which he intended to buy by the thousand. Jacqui Smith, the home secretary, has said the government is taking the threat seriously and a computer simulation of a radiological attack on London was carried out by the Home Office last year. Senior officials in the Bush administration took part in a similar exercise last year, involving three simultaneous dirty bomb blasts, and Spain, another recent terrorist target, carried out a drill earlier this year.

Meanwhile, radiation detectors are being installed in ports around the world, as a last line of defence against a smuggled nuclear device. So far they have produced literally millions of false alarms (a particular potassium isotope in bananas, for example, can set off the sirens). The White House has its own nuclear bomb squad, which it scrambled in 2005 to intercept US-bound ships suspected of carrying a weapon. It turned out they were carrying scrap metal contaminated by illegally dumped radioactive material.

This is the emerging battlefield of the 21st century. Western governments have little idea whether they are being overly paranoid or recklessly negligent in their preparations. The potential is so horrifying, there seems little choice but to prepare for the worst.

The Guardian,