Extremely high levels of radioactivity can kill anyone coming into contact with it — or just getting too close to it — within a matter of days or weeks. Radioactive materials slowly lose their radioactivity and so can become in theory safe to handle but in most cases this is a very slow process. Plutonium, for instance, has a half-life of over 24, years which means it will remain lethal for over , years.
Other radio-isotopes remain radioactive for millions or even billions of years. The safe, long-term storage of nuclear waste is a problem that is reaching crisis point for both the civil nuclear industry and for the military. During the Cold War years of the s and s, the development of the British atomic bomb was seen as a matter of urgency.
Dealing with the mess caused by the production, operating and even testing of nuclear weapons was something to be worried about later, if at all. For example, the Ministry of Defence does not really have a proper solution for dealing with the highly radioactive hulls of decommissioned nuclear submarines, apart from storing them for many decades. As a result, 19 nuclear-powered retired submarines are still waiting to be dismantled, with more expected each year. Yet Britain goes on building these submarines.
This callous disregard for the future has spilled over to the nuclear power industry. For example, at Dounreay, in the north of Scotland, nuclear waste and scrap from the experimental reactor and reprocessing plants were simply tipped down a disused shaft for over 20 years.
No proper records of what was dumped were kept and eventually, in , an explosion showered the area with radioactive debris.
The problems of long term, secure storage of nuclear waste are unsolved and growing more acute year by year. Earlier attempts by the nuclear industry to get rid of it by dumping it in the sea were stopped by environmental direct action, trades union protests and now by law. All details concerning military nuclear waste are regarded as official secrets.
However, large and growing quantities of radioactive waste exist at the Rosyth and Devonport dockyards and in particular at the Aldermaston and Burghfield Atomic Weapons Establishments. One feature of Aldermaston and Sellafield in particular is that they are old sites, and have grown up in an unplanned, haphazard way. New buildings are fitted in between old, sometimes abandoned, buildings.
Some areas and buildings are sealed off and polluted by radioactivity. Local streams, and in the case of Sellafield the sea shore, are polluted. The demolition of old radioactive buildings is a delicate, slow and dangerous process. In the circumstances it is hardly surprising that the amount of nuclear waste can only be estimated. Civil intermediate level solid waste is mainly stored at Sellafield awaiting a decision on a national storage facility.
Military intermediate level solid waste is stored where it is created: dockyards, AWE plants etc. Both civil and military high level solid waste is generally moved to Sellafield for temporary storage.
The major problems are with the long-term storage of intermediate and in particular high-level wastes. Since these are very dangerous and very long-lived, any storage facility has to be very secure i.
Because of this very long time scale, it can never be sealed up and forgotten. Containers corrode with time. There are earth movements. Water seeps through rocks. The waste will have to be stored in such a form that it cannot be stolen and misused and in such a way that it can be inspected and if necessary retrieved and moved.
Plans to dig a trial deep storage facility under the Sellafield site were thrown out in Geological evidence suggested that the local rock is too fissured and liable to be affected by water seepage. Instead of having a storage site ready by , the date has been put back more or less indefinitely. No alternative site has even been identified.
Apart from the technical, geological problems, few communities seek a huge, long-term nuclear waste storage site in their neighbourhood. The time and resources needed to make the transition from latent to active proliferation can range from very large to very small. Inadequately controlled plutonium or highly enriched uranium, combined with secret design and testing of non-nuclear components of nuclear warheads, can allow a nation or terrorist group to have deliverable nuclear weapons within days, or even hours, after acquiring a few kilograms or more of the key nuclear weapon materials.
Contrary to widespread belief among nuclear engineers who have never worked on nuclear weapons, plutonium made in nuclear power plant fuel can be used to make all types of nuclear weapons. In early nuclear weapons, such as the plutonium bomb tested in New Mexico in , and then used in the bombing of Nagasaki, use of reactor grade plutonium would have tended to cause the chain reaction to start prematurely.
This would lower the most likely explosive yield, but not below about 1 kiloton, compared with the 20 kiloton yield from these two bombs. Reactor grade plutonium can also be used for making relatively crude nuclear explosives, such as might be made by terrorists. Although the explosive yields of such bombs would tend to be unpredictable, varying from case to case for the same bomb design, their minimum explosive yields could credibly be the equivalent of several hundred tons or more of high explosive.
All nuclear weapons require plutonium or highly enriched uranium. Some use both. The required amounts vary considerably, depending on the desired characteristics and on the technical resources and knowhow available to those who design and build the weapons.
Estimates of the maximum total number of U. Nuclear power plants typically produce a net of about kilograms of plutonium per year for each 1, megawatts of electric power generating capacity.
Some nuclear power plants, with combined electrical generating capacity of nearly , megawatts, are now operating in 32 countries. Total net annual production of plutonium by these plants is nearly 70, kilograms, enough for making more than 10, nuclear warheads per year. So far about four times as much plutonium has been produced in power reactors than has been used for making nuclear weapons-about 1 million kilograms, most of which is in spent nuclear fuel in storage, compared with about , kilograms for weapons.
Nearly , kilograms of plutonium have been chemically separated from spent power reactor fuel in chemical reprocessing facilities in at least 8 countries Belgium, France, Germany, India, Japan, Russia, United Kingdom, and United States.
Research and test reactors can also produce significant amounts of plutonium that, after chemical separation, can be used for making nuclear weapons. This has apparently been the route to nuclear weapons followed by Israel and started by North Korea.
Principal suppliers have been and now are the five declared nuclear weapon states. It has been estimated that the world inventory of highly enriched uranium for civil purposes is about 20, kilograms. Although this is dramatically smaller than the more than 1 million kilograms of highly enriched uranium associated with nuclear weapons, it may be extremely important to some countries that are secretly developing the technology for making nuclear weapons.
Facilities for enriching uranium in its concentration of the isotope U to the levels of a few percent needed for light water power reactor fuel can be used for further enrichment to high concentrations used for making nuclear explosives. The technology for doing this is proliferating, both in terms of the numbers of countries that have such facilities, and in the variety of different ways to carry out the enrichment.
The continuing international spread of knowledge of nuclear technology related to nuclear power development is an important contributor to latent nuclear weapon proliferation.
Some of the people who have become experts in nuclear technology, whether for military or civil purposes, could be of great help in setting up and carrying out clandestine nuclear weapon design and construction operations that make use of nuclear materials stolen from military supplies or diverted from civil supplies, perhaps having entered a black market.
An example of highly advanced latent nuclear weapon proliferation is the nuclear weapons development program that started in Sweden in the late s.
It remained secret until the mids, when much detail about the project started becoming publicly available. It included hydronuclear tests of implosion systems containing enough fissile material to go critical but not enough to make a damaging nuclear explosion. The objective of the Swedish nuclear bomb program was to determine, in great detail, what Sweden would need to do if the government ever decided to produce and stockpile nuclear weapons.
Another type of latent proliferation that I find especially worrisome is the possible bombardment of nuclear facilities that thereby would be converted, in effect, into nuclear weapons. Military bombardment or sabotage of nuclear facilities, ranging from operating nuclear power plants and their spent fuel storage pools to large accumulations of high level radioactive wastes in temporary or long term storage, could release large quantities of radioactive materials that could seriously endanger huge land areas downwind.
Electric power plants and stored petroleum have often been prime targets for tactical and strategic bombing, and sometimes for sabotage. In the case of operating nuclear power plants, core meltdowns and physical rupture of containment structures could be caused by aerial or artillery bombardment, truck bombings, internal sabotage with explosives, or by control manipulations following capture of the facility by terrorists. For orientation to the scale of potential radioactive contamination, consider strontium and cesium, two especially troublesome fission products with half-lives of about 30 years.
The inventories of these radionuclides in the core of a typical nuclear power plant 1, electrical megawatts are greater than the amounts released by a 20 megaton H-bomb explosion, assuming half the explosion energy is accounted for by fission. Inventories of dangerous radioactive materials can be considerably greater in a waste or spent fuel storage facility that has served the needs of many nuclear power plants for many years.
In some cases it may not be credible that chemical explosives could release large fractions of such materials and cause them to be airborne long enough to contaminate very large areas. In such situations, however, the explosion of a relatively small nuclear explosive in the midst of the storage area could spread the radioactive materials over huge areas.
Perhaps the greatest extent of latent proliferation of nuclear weapons is represented by nuclear power fuel cycle facilities that can become enormously destructive nuclear weapons by being bombed by military forces or terrorists. Given the rapidly increasing rate of worldwide latent proliferation of nuclear weapons, what can be done to assure that it does not lead to considerable surges in active proliferation of nuclear weapons?
But the IAEA has authority only to inspect designated or in some cases suspected nuclear facilities, not to interfere physically to prevent a government from breaking its agreements under the treaty if it so chooses. Furthermore, a major function of the IAEA is also to provide assistance to countries that wish to develop nuclear power and use it.
Thus the IAEA simultaneously plays two possibly conflicting roles-one of encouraging latent proliferation and the other of discouraging active proliferation. Such a decision might be made secretly or openly at any time government leaders conclude that threats to their security or ambitions of conquest warrant breaking safeguard agreements; at that point they can quickly extract the key nuclear materials needed for a few or for large numbers of nuclear weapons. Various proposals have been made for developing nuclear power in forms that are less prone to diversion of nuclear materials for weapons than present nuclear power systems.
None of these proposals avoid the production of substantial quantities of neutrons that could be used for making key nuclear materials for nuclear weapons, however. And none avoid the production of high level radioactive wastes, the permanent disposal of which is still awaiting both technical and political resolution. The high spontaneous fission rate of Pu acts as a kind of poison in the core of nuclear bombs. Typical commercial power reactor fuel cycles are around two years.
If the fuel cycle is shorter the electricity becomes uneconomic. All this means that the plutonium than can be extracted from the fuel rods of a commercial nuclear power reactor is not suitable for making nuclear weapons. There are 31 nations with nuclear power stations and 58 with research reactors.
Only seven of the nine nuclear-armed countries have civilian power programs. All of the technical factors can be circumvented with sufficient time and money. Uneconomic fuel cycles can be run and warheads built with high levels of radioactivity. However, no country has developed indigenous nuclear weapons after deploying civilian nuclear power stations. Historically, if a country wants to produce a nuclear bomb, they build reactors especially for the job of making plutonium , and ignore civilian power stations.
Portsmouth Climate Festival — Portsmouth, Portsmouth. Edition: Available editions United Kingdom. Become an author Sign up as a reader Sign in. Patrik Hermansson.
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