The Threat of Nuclear Terrorism

By Sam Nick Alvaro | 1996-07-01 12:00:00

Since the end of the Cold War, fear of a nuclear war has faded as did the yo-yo and hula hoop. Actually, nuclear mishap now may be more likely than ever. However, the fear now is not concerned with "mutually assured destruction" but from nuclear terrorism. Devices might be placed in such settings as the Paris subway, the World Trade Center, an Oklahoma government building, or a university favored by the Unabomber. What should we do about such possibilities?

The Uranium Threat

Non-proliferation groups, such as the Nuclear Control Institute (NCI), have promoted U.S. government policies to end civilian uses of bomb-grade uranium. Highly enriched uranium (HEU) is uranium with the isotope U-235 in a concentration greater than 20 percent. Concentrations of 90 percent or higher are generally required for nuclear weapons and are called "weapons- grade" uranium. Commerce in such material is especially dangerous because of the relative ease with which it can be made into nuclear weapons. Terrorists possessing modern weapons-grade uranium would have a good chance of setting off an explosion simply by dropping one half of it onto the other half.

International trade in HEU began with little foresight in the 1950s under the Atoms for Peace program. Over the next three decades, the United States exported dozens of nuclear research reactors and HEU - the same material used in the Hiroshima bomb. If stolen, less than 25 kilograms of this material would suffice to build a nuclear weapon.

Not until the 1970s did the U.S. government appreciate fully the proliferation dangers of such commerce. Carter Administration officials realized that the HEU in research reactor fuel could be diverted by nations or terrorists for nuclear explosives. Most research reactors are on university campuses and centers where security is lax and access to this material relatively unfettered.

The Plutonium Threat

Plutonium, a man-made element, was first produced in gram quantities during World War II. Today there is a growing awareness of the threat it poses. Thus a recent study by the RAND Corporation stated, "It is critical that countries pay attention to the proliferation threat from the civilian side if they want to maximize the nonproliferation value of dismantling U.S. nuclear weapons and those of the former Soviet republics."1

There is actually far more plutonium in civilian than in military nuclear programs. More than 1,200 metric tons of it have been produced in reactors. Of this, about 260 tons have been produced for weapons. All the rest, nearly three times as much, has been produced in civilian nuclear power reactors. With the end of the nuclear arms race, the amount of military plutonium is expected essentially to stay constant and then decline as plutonium from retired warheads is disposed of. But the civilian plutonium produced in power reactors will grow from 650 tons in 1990 to 2,100 tons in the year 2010 - more than eight times the amount of weapons plutonium.

Reprocessing, Big Time

A major difference between military and civilian plutonium is that most military plutonium has been chemically separated ("reprocessed") from the spent fuel of reactors for direct use in weapons, while most civilian plutonium remains embedded in spent fuel. As long as plutonium remains in highly radioactive spent fuel, it is not immediately accessible for weapons.

However, commercial reprocessing of spent fuel from civilian power reactors is now getting underway on a large scale. The impact of this reprocessing is startling: While in 1990 there was more than twice as much separated, weapons- usable plutonium in military as in civilian programs, by the year 2000 more plutonium suitable for direct use in weapons will exist in civilian than in military programs for the first time. By the year 2010, there will be nearly 550 tons of civilian, weapons-usable plutonium - more than twice the amount in military programs.

Considering that less than 18 pounds of plutonium is enough for a Nagasaki-type bomb, the proliferation risk of all this potential weapons material is enormous. The ostensible purpose of commercial reprocessing is the recovery of plutonium for "recycling" as fuel in power reactors. If, when the Non-Proliferation Treaty (NPT) came into force 25 years ago, there may have been an economic rationale for reprocessing spent fuel and recycling plutonium, that is no longer the case. At that time, it was feared that world reserves of uranium could not keep pace with demand for reactor fuel, resulting in a shortage of the non-weapons-usable uranium fuel used in civilian power reactors. Today there is a world glut in cheap uranium, and plutonium-based fuel for power reactors is four to eight times more expensive than comparable uranium fuel.

Only five nations engage in commercial reprocessing today - Britain, France, India, Japan, and Russia. Reprocessing capacity is shown by weight of the spent fuel reprocessed annually (metric tons of heavy metal per year). Plutonium constitutes about one percent of the weight of the spent fuel.

The great risk is the inability of the International Atomic Energy Agency (IAEA) to detect losses of weapons quantities of plutonium from large processing facilities. The IAEA faces substantial uncertainties in measuring plutonium, which tends to stick to the surfaces of plant equipment, where it is difficult and hazardous to clean out. There are also limitations to the agency's surveillance and containment measures. The difficulty of safeguarding plutonium was recently shown at a pilot-scale plutonium fuel fabrication plant in Japan, where the IAEA has required the operator to clean out the plant and produce nearly 70 kilograms of plutonium that is reportedly stuck in the processing equipment--a procedure expected to take two years to complete. Under such circumstances, the IAEA cannot fulfill its timeliness and detection goals, which are designed to meet the safeguards requirement of the NPT, "preventing diversion of nuclear energy from peaceful uses to nuclear weapons."

Transportation of the plutonium and the waste byproducts of reprocessing poses other safety and environmental hazards. Plutonium is fiendishly toxic; microgram quantities embedded in the lungs after inhalation or in bones after ingestion cause cancer. In 1987, Japan canceled plans to transport its plutonium by air from Europe after failing to develop a crashworthy shipping cask. In 1992, over 40 nations protested against Japan's first large-scale shipment of plutonium by sea after it became known that international standards for the shipping cask were below the fire, collision, and deep-immersion conditions experienced in severe accidents. If a nation such as Japan cannot properly handle nuclear material, what does this mean for the terrorists who smuggle HEU?

Nuclear Terrorism

Developments in the Middle East, evidence of nuclear smuggling from the former Soviet Union, along with terrorist attacks in Manhattan and Oklahoma City, have amplified the grounds for concern about nuclear bombing.

Beyond the threat of nuclear smuggling and civilian nuclear terrorism, nations that stockpile tons of plutonium and bomb-grade uranium for peaceful purposes could convert these fuels into nuclear weapons at any time.

The NCI has seen two issues that must be raised by the bombing of urban centers in the United States. The first question is whether nuclear power plants would be vulnerable to a meltdown if successfully attacked with a bomb of that size. The second question concerns the adequacy of international efforts to improve physical protection over nuclear materials and retired warheads; to develop contingency responses to nuclear theft; and to improve technical capabilities for finding and disarming terrorist nuclear bombs in order to thwart extremists seeking to make such weapons.

Regarding the first issue, the NCI and the California-based Committee to Bridge the Gap succeeded in getting the NRC to require nuclear power plant operators to install defenses against truck bombs. That rule apparently defends against a bomb as large as the one used at the World Trade Center. However, since the Oklahoma bombing, this policy implementation may need to be amended.

Seizure of almost three kilograms of HEU from nuclear smugglers arrested in 1994 in the Czech Republic dramatically illustrates the breakdown in controls over weapon-usable nuclear material in the former Soviet Union, the suspected source of the material. It also makes clear that the risk of nuclear terrorism is growing. Steven Dolley and Paul Leventhal of NCI have analyzed the extent to which the threat of nuclear terrorism is possible. Three seizures of plutonium and one of HEU in Germany took place during the summer of 1993, showing the emergence of a black market in nuclear materials being smuggled out of the former Soviet Union.2 These seizures were relatively small compared to the seizures of HEU that were also reported to have taken place: one involving six pounds in St. Petersburg in March 1994; one of three pounds near Moscow in October 1992; and one of about 4.5 pounds in Lithuania in 1992.

How much HEU is needed to make a nuclear bomb? A research team at the University of California (Santa Cruz) found that three kilograms would be sufficient. By means of computer modeling of a simple fission weapon design, they found a nuclear yield equivalent to more than 100 tons of high explosives could be achieved with only one kilogram of HEU and "a yield half that of the Hiroshima bomb" with five kilograms.3 They concluded that one can make an atomic weapon with much less nuclear material than thought, and urged that the use of HEU be eliminated in order to prevent the spread of small-scale atomic weapons.

Further, terrorists need not build an actual nuclear bomb in order to cause nuclear violence. Less than three kilograms of HEU would be sufficient to construct an easily transportable and concealable "chain-reacting radiological weapon." While not producing a nuclear explosive yield, such a device could be made to go "super-critical" and disperse lethal amounts of radioactivity over a radius of hundreds of yards.

Can HEU be used on its own to make nuclear bombs, or is it strictly a triggering material for hydrogen bombs? The Hiroshima bomb was a fission weapon fueled solely with HEU. Iraq, Pakistan, and South Africa chose to base their covert nuclear weapons programs on HEU.4 Thus, HEU was both a fuel for first-generation nuclear weapons and a potential trigger for more advanced thermonuclear weapons.

How Complex Is The Design?

Are nuclear weapons too complex to be built by terrorist groups? An anonymous "nonproliferation expert" has been cited as claiming that "while assembling enough fissile material is the most expensive and difficult part of constructing a bomb, those seeking to produce their own nuclear weapons must also secretly develop an effective detonation system and a delivery means, such as a missile or special aircraft."5 The first part of the statement is worth emphasizing. Without HEU or plutonium, building a nuclear weapon is impossible. Construction of nuclear weapons is relatively straightforward for sophisticated terrorists or proliferating states once these materials are in hand.

A panel of five former U.S. nuclear weapons designers reported to the International Task Force on the Prevention of Nuclear Terrorism that a workable nuclear bomb "could be constructed by a group not previously engaged in designing or building nuclear weapons, providing a number of requirements were adequately met,"6 and that even such a crude design could produce a yield in the 10 kiloton range. College students, with no access to classified information, have produced workable designs for nuclear fission weapons and even thermonuclear weapons. The particular properties of HEU simplify the weapon design process. Luis Alvarez, a physicist with the Manhattan Project, noted in his memoir that "with modern weapons-grade uranium, the background neutron rate is so low that terrorists, if they had such material, would have a good chance of setting off a high-yield explosion simply by dropping one half of the material onto the other half; even a child could do it."7

The easiest way for a terrorist group to obtain such material is to acquire weapons-usable plutonium, created in civilian reactors that generate electricity for cities rather than in military reactors that produce material for bombs. The problem is that although the intended use of these two types of reactors differs, the byproduct is the same: plutonium, an essential ingredient of nuclear weapons. Civilian power reactors are typically much larger than military production reactors and therefore produce many times more plutonium. The nuclear industry is well on its way to introducing this plutonium on the world market as a commercial fuel, as it does uranium. The uranium now used in reactors is a low grade that cannot be used in weapons, but the plutonium can be used either for fuel or for bombs.

The United States no longer reprocesses spent fuel of power reactors at home for both economic and non-proliferation reasons. Seventy-five percent of the plutonium being extracted today in Europe and Japan is from U.S.-supplied nuclear fuel, but these countries do not enforce the same non-proliferation laws that restrain plutonium programs in the United States. The U.S. has given political interests with allies clear precedence over its obvious security interest in making sure that its nuclear fuel exports do not end up as weapons-usable plutonium in world commerce. As a result, U.S.-origin plutonium is now beginning to enter world commerce in frightening amounts.8

Nuclear Security In The Former Soviet Republics

In June 1994, Dr. William C. Potter, Director of the Center for Nonproliferation Studies at the Monterey Institute of International Studies, testified to the Subcommittee on International Security, International Organizations, and Human Rights of the U.S. Congressional Committee on Foreign Affairs. He stated his growing pessimism about the nuclear insecurity in the post-Soviet states, because of: (a) credible reports that for the first time weapons-grade plutonium may have been smuggled out of Russia; (b) evidence of serious deficiencies in the national safeguards system in Russia and the other successor states which possess nuclear assets; and (c) growing pressures in Russia to subordinate the objective of stringent export controls to those of hard currency exports and personal profit.

Although the details remain unclear, approximately six grams of weapons-grade plutonium were recovered from a small canister seized in an apartment near Konstanz in May 1994. It was mixed with 50 grams of an alloy that probably originated in the waste streams of metallic plutonium production at a reprocessing facility in Russia.

The Cooperative Threat Reduction Program has emphasized the rapid transfer of nuclear weapons to Russian territory and their dismantlement. More attention, however, must be given to improving the national safeguards system in Russia and the former Soviet republics to prevent theft of weapons-grade material by organized crime from civilian nuclear facilities.

All of the former Soviet states with nuclear assets have defective safeguards of nuclear material. Particularly worrisome are suspect security and accounting procedures at nuclear fuel storage facilities for propulsion reactors, plutonium storage facilities for dismantled weapons, and sites for research reactors, critical assemblies, and fast breeder reactors. Due to sloppy accounting practices in the past, few of the former Soviet republics can even determine the quantity of HEU at their own facilities. One can imagine the uncertainty at nuclear facilities in Russia that possess HEU and plutonium stocks thousands of times larger. Under such conditions, it is probably impossible at the present time to distinguish between "material unaccounted for" and material that has been stolen. Nevertheless, it must be acknowledged that plutonium storage facilities are ulnerable to theft, especially in light of the following complicating factors: the enormous quantities of weapons-grade material in question; the growing disaffection of large segments of the Russian population; plummeting morale in the Russian military and the nuclear industry; the widespread disregard in Russia for law; pervasive corruption throughout the government; the increasing reach of organized crime; and an economic malaise that encourages the plunder and sale of government property. According to a recent study by Russian physicist Oleg Bukharin, there are severe shortages of trained personnel and modern equipment, adequate material transport control procedures, storage, and processing facilities.9

Another factor is the former Soviet states' inexperience in export controls. If a terrorist group bribes someone to obtain HEU for them they still must be able to transport it across the border. However, porous frontiers between Russia and the other Soviet successor states make it a simple matter to ship illicit goods from Russia to the other former republics. Action has been taken to remedy these shortcomings. In 1992, eight of the former Soviet states reached an agreement on export control coordination, although it has yet to produce the intended results. They have been undermined by severe budget constraints, a shortage of trained personnel (aggravated by the migration of many government professionals to the more lucrative private sector), the absence of legislation governing nuclear energy and nuclear exports, and the low priority most policy makers attach to nuclear nonproliferation and export controls.

The problems identified here are all rooted in the economic, political, and social conditions of contemporary Russia. As such, they are unlikely to be resolved until progress is made in stabilizing the economy and in restoring public trust in governmental institutions, law, and social justice. These changes will not occur soon, and foreign nations, including the United States, can make only a marginal difference. Nevertheless, we should try to do so.

In the fall of 1991, conditions in the disintegrating Soviet Union created a threat to nuclear safety and stability. An estimated 30,000 nuclear weapons were spread among the former Soviet republics. About 3,200 strategic nuclear warheads were located outside of Russia. These conditions also caused concerns that former Soviet nuclear weapons scientists and engineers would export their expertise or services to rogue countries and groups. Although significant positive changes were occurring in the Newly Independent States and many of the threats of the Cold War were disappearing, these weapons and materials continued to pose global security risks. The spectre that nuclear materials could be smuggled out of Russia increased anxiety that, unless action was taken, it would be only a matter of time before sufficient materials to build a bomb fell into the hands of rogue states.

It Is Not Too Late

Humankind stands at a fork in the road. The low road ahead is to keep using plutonium as a commercial fuel on the premise that it will be protected against misuse for bombs by nations and concerned groups. The high road leads to a ban on civilian plutonium. There is still time to choose between these paths. Plutonium is an essential weapons material, but not an essential reactor fuel. We can choose to phase out nuclear power (see Kristen Ostling's article on this option in the May/June Peace Magazine) but even if we are slow to do so, ample reserves of inexpensive uranium exist to keep power reactors operating. Low-grade uranium fuel for power reactors is four to eight times cheaper than mixed plutonium-uranium fuel. The plutonium industry, originally established to offset an anticipated uranium shortage, is no longer needed. But the factories it has built in the meantime to extract plutonium and fabricate it into fuel are beginning to start up nonetheless.

The question is not whether we can live without civilian plutonium, but whether the world can live with it. If present plans proceed, many hundreds of tons of separated plutonium will have to be protected in the decades ahead against the loss of the few pounds needed for a the turn of the century, 1,400 metric tons of plutonium will have been produced in the spent fuel of nuclear power reactors, and some 300 tons of it will have been separated into weapons-usable form. The amounts will continue to grow rapidly. By 2010, there will be 550 tons of separated plutonium in commerce, more than twice the amount now contained in the world's nuclear arsenals. Assuming that the technology and materials suitable for making nuclear weapons continue to spread as articles of commerce, nuclear proliferation and the closely connected threat of nuclear terrorism will become a principal danger of our time.

The "G-8 Summit on Nuclear Safety" took place in Moscow in April 1996 to promote cooperation on nuclear safety problems. The leaders combined their nations' experience as users of nuclear power to consider the safety of civil nuclear reactors; the management of radioactive waste; and the security of nuclear materials. They considered ways of strengthening cooperation in the following areas:

These are only the first steps toward nuclear security, but they are overdue. Any educated person today can go to a public library and find out how to build a nuclear device. Anyone with Internet access can obtain working diagrams, such as the one shown on page 13, for constructing nuclear weapons. There is no way to block this information, but we can block the accessibility of fissile materials. If the world's states do not do so, we must expect the worst.

Sam Alvaro is a recent graduate of Erindale College, University of Toronto.

Peace Magazine Jul-Aug 1996

Peace Magazine Jul-Aug 1996, page 11. Some rights reserved.

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