The "nuclear fuel cycle" is an astonishing piece of terminology that has established itself in common parlance over the past decades although it is constantly refuted by reality. The myth of the nuclear fuel cycle is based on an early dream of nuclear engineers, namely that the fissile plutonium produced by commercial uranium reactors could be separated out in reprocessing plants and then used in fast breeder reactors - creating in effect a perpetuum mobile from non-fissile uranium (U-238) to plutonium (Pu-239) for more breeder power plants. The idea was to create a gigantic industrial cycle with more than a thousand fast breeder reactors and dozens of reprocessing plants on a large civilian scale such as that found today only at La Hague in France and Sellafield in Britain. In the mid-1960s, nuclear strategists were forecasting that Germany alone would possess a fleet of breeders with an overall capacity of 80,000 megawatts by the year 2000 but the plutonium route in nuclear technology, which German expert Klaus Traube who once directed the Kalkar reactor project on the Lower Rhine later called the "utopian solution of the 1950s" (Erlösungsutopie der 50er Jahre), 9 became possibly the greatest fiasco in economic history.
9 Klaus Traube: Plutonium-Wirtschaft? (Hamburg, 1984), p. 12
Breeder technology is exorbitantly expensive, technically undeveloped, even more controversial with respect to safety than conventional nuclear plants, and especially vulnerable to military exploitation. It has yet to gain ground anywhere in the world. Only Russia and France each operate a single breeder reactor stemming from the early development period. Japan (whose prototype breeder in Monju has been idle following a severe sodium fire in 1995) and India are officially pursuing development in this area but without prospects for further developments in breeder technology, the main historical motivation for separating out plutonium at reprocessing plants now no longer applies.
In addition to France and Great Britain, Russia, Japan and India operate smaller reprocessing plants for the retroactively declared purpose of re-using the plutonium generated in conventional light-water reactors in the form of so-called mixed oxide (MOX) fuel rods. When not shut down due to technical problems, reprocessing plants generate horrendous costs along with their plutonium and uranium. They also produce highly radioactive nuclear waste that requires permanent disposal, as well as radiation levels exceeding those of light-water reactors by a factor of ten of thousands. Reprocessing also requires frequent precarious transports of highly radioactive materials, some of which would be suitable for military or terrorist purposes thus greatly increasing the number of possible targets for terrorist groups.
Because a comparatively small proportion of the highly radioactive nuclear waste generated in commercial power plants is reprocessed, and because spent MOX fuel rods are generally not recycled again, the only part of the nuclear fuel cycle that remains is the name. In the real world, this cycle is open. In addition to electricity, nuclear power plants generate waste products that cover the spectrum from highly to weakly radioactive, and which are highly toxic. They require secure disposal sites for enormous periods of time that depends on the natural, so-called half-time periods of the radionuclides, which differ greatly. The plutonium isotope Pu-239 loses half its radioactivity in 24,110 years; the cobalt isotope Co-60 does so in 5.3 days.
Half a century after nuclear power plants started producing electricity, there is not one single authorised and operational final disposal site for highly radioactive waste - a state of affairs that recalls the well-known image of the atomic airplane taking off without any one considering where it will to land. In some countries - such as France, the USA, Japan and South Africa - comparatively short-term and low to medium radioactive waste is stored in special containers near the earth's surface. Germany has prepared the "Konrad" former iron ore shaft in Salzgitter in the state of Lower Saxony for the underground storage of non-heat-generating waste from nuclear plants, as well as from research reactors and nuclear medical applications. However, storing nuclear waste in this former ore pit continues to be the subject of legal dispute. The initial lack of concern about nuclear waste was evident in a 1969 statement by the above-mentioned physicist and philosopher Carl Friedrich von Weizsäcker. "It won't be a problem at all," he said. "I've been told that all the atomic waste that will accumulate in Germany until the year 2000 will fit in a cubic container measuring 20 metres in length. If that is well closed and sealed and placed in a mine, we can hope to have solved this problem."10 In the meantime, exotic early proposals such as storing the waste in space, at the bottom of the sea, or in the ice of Antarctica have vanished from public view. Experts cannot decide whether granite, salt, clay or other minerals represent the best substrate for long-term storage of highly radioactive and heat-generating waste -all cite both advantages and disadvantages for every option.
The question of whether radioactive waste can be safely isolated from the biosphere for hundreds of thousands or millions of years is ultimately philosophical. It defies human imagination. The pyramids, after all, were built a mere 5,000 years ago. One thing is clear though, because nuclear waste exists, and because the question of long-term storage cannot be answered conclusively, the best technical solution based on the latest state of knowledge has to be sought and found. Attempts to avoid the issue do not help matters at any rate. An example of this would be so-called transmutation, whose advocates propose constructing special reactors to split the most hazardous and persistent waste into isotopes that will only be radioactive for a few hundred years. For decades now, only a small number of scientists have considered this prospect seriously but even proponents presumably do not really believe it can significantly reduce the most hazardous by-products of nuclear technology.
To put transmutation technology into practice, innovative reprocessing plants, in which the highly radioactive isotope cocktail from nuclear power plants would be broken down via complex chemical processes into individual elements using far more sophisticated systems than in existing plants would first have to be built. The plutonium plants at La Hague and Sellafield would be like simple chemical laboratories in comparison. Moreover, a fleet of reactors would have to be developed in which the separated isotopes could be selectively bombarded with so-called rapid neutrons, split, and transmuted into less hazardous radionuclides. Even if it were technically feasible to build these plants, nobody could or would be willing to fund this type of nuclear infrastructure. This disposal method would undeniably carry far greater risks than the final disposal policy currently pursued in many countries, namely in carefully selected underground repositories. The fact that despite these considerations, the notion of transmutation survives primarily in France and Japan has more to do with the breeder visions still nurtured by parts of their respective nuclear communities than with serious prospects of it being put into practice.
10 Cited in B. Fischer, L. Hahn, et al: Der Atommüll-Report (Hamburg, 1989), p. 77
Gradually and belatedly, the major nuclear-power producing countries are reaching the conclusion that selecting a final disposal site is more than a scientific or technical problem. None of the national site selection programmes, most of which were launched in the 1970s, has yet produced an authorised final repository. This is because the selection procedures have ignored or rejected public opposition, democratic participation and transparency for far too long. In attempting to learn from these mistakes, Germany developed and formulated a multi-stage selection process with public participation throughout. It is not yet clear whether this process, which was agreed by scientists from both the pro and anti-nuclear energy camps in 2002 following years of intensive debate, has a realistic chance of success. The CDU/CSU and SPD coalition government elected in the autumn of 2005 has initially postponed the question of whether to seriously consider other final disposal sites than the salt dome in Gorleben prepared back in the 1980s.
Final disposal plans in Finland and the USA are relatively far along at present. The gigantic facility at Yucca Mountain in Nevada, however, has been the object of controversy for decades while the largely finished site at Olkiluoto in Finland has benefited from a comparatively high acceptance by local and regional populations. The majority of residents are reassured by the fact that no major failures have occurred for many years at the nuclear power station in Finland, as well as by an already functioning final repository for low and medium radioactive waste.
The putative fuel cycle is not only open at the back end, however. From the very beginning, it has also been highly problematic at the front end. Uranium mining operations to acquire the fissile material for the bomb and later for civilian power plants have claimed a huge toll, especially in the early stages. Large amounts of radioactive nuclides, which had been shielded by the earth's crust, have entered the biosphere. Maintaining or expanding nuclear power will considerably increase the health and environmental costs associated with uranium mining. The search for this heavy metal, which is not particularly rare as such but whose concentrated deposits are few in number, started shortly after World War Two. The horrific effects of the US bombing of Japan did not inhibit, but rather spurred, Allied ambitions to develop strategic resources. Great efforts were made to expand and secure access to uranium. At the time, miners' health and environmental issues played merely a subordinate role. The USA worked mines both on its own territory and in Canada, while the Soviet Union developed uranium mines in East Germany, Czechoslovakia, Hungary and Bulgaria. Thousands of miners met painful deaths from lung cancer after years of heavy labour in poorly ventilated, dusty tunnels contaminated with radioactive radon. Some of the hardest hit were those at the East German "Wismut" facility, which at times employed more than 100,000 people. As uranium concentrations in the earth generally only differ by tenths of a percent, large amounts of excavated earth accumulated. The exposed uranium ore contained relatively high concentrations of radon gas and other radioactive nuclides. This resulted in severe and long-term radioactive exposure not only for the miners themselves, but also for the surrounding area and its residents. Extraction processes using liquid reagents, which contaminated the surrounding land, surface water and ground water, exacerbated the problem.
The situation improved with the boom in nuclear electricity generation in the 1970s. From then on, governments were no longer the sole purchasers of fissile material. A private uranium market developed, which meant that the very harsh working conditions could no longer be ascribed to the special military and strategic status of uranium mining. With the end of the Cold War, conditions underwent another fundamental change. The military demand for uranium declined steeply. Deposits no longer required by the USA or the former Soviet Union could now feed the civilian market for fissile material. Moreover, as nuclear disarmament proceeded, large amounts of weapons-grade uranium with high fissile content quickly became available from the now superfluous Soviet and American nuclear stockpiles. This may have been the most comprehensive programme ever for converting instruments of war to civilian commercial purposes. Large amounts of the highly explosive weapons material were "diluted" with natural or so-called depleted uranium (U-238 from which the fissile U-235 isotope was extracted) and then used as fuel for conventional nuclear power plants. This completely new development on the market caused international prices for reactor-grade uranium to plummet, which meant that only relatively high-volume deposits were still mined. On into the year 2005, almost half of the uranium split in nuclear power plants around the world was no longer coming from enriched, "fresh" uranium ore, but rather from the superpowers' military stockpiles.
In the foreseeable future, however, uranium supplies from the Cold War will run out. Uranium prices have already begun to rise, and will continue to do so at an accelerated pace. If nuclear power plants are to continue operating at today's level or if the reactor fleet is expanded, old mines will have to be re-opened, as will new deposits with ever lower yields, which in turn will mean ever smaller amounts of uranium and ever greater volumes of waste rock with above-average concentrations of radioactive isotopes - with all the attendant health and environmental risks. Furthermore, the industry needs time to expand its uranium mining capacities, which it will not have if nuclear energy generation is to expand rapidly. As also happens during periods of cheap oil, exploration efforts slowed down greatly after the release of surplus military stockpiles, so we only know of relatively few deposits today. Moreover, it takes an average of at least ten years from the time a uranium deposit is identified to the point when mining can start.
The approaching bottleneck in uranium supplies will be exacerbated by a huge imbalance between supply and consumer countries. Canada and South Africa are the only nuclear- energy producing countries that are not dependent on uranium imports. The major countries that use nuclear power either have essentially no uranium production of their own (France, Japan, Germany, South Korea, Great Britain, Sweden, Spain) or considerably smaller capacities than would be needed to sustain the operation of their reactors over the long term (USA, Russia). As far as its fuel supply is concerned, nuclear power is a domestic source of energy almost nowhere in the world. Russia in particular risks facing a serious uranium supply crisis in 15 years already. This shortage could then be shifted to plant operators in the EU who currently acquire about one third of their fuel from Russia. China and India could also face a fuel shortage if both expand their reactor fleet as announced.
Given the above considerations, the following is clear: neither fuel supply nor waste disposal for the world's nuclear power plants can be secured over the long term. The new reactors planned and under construction in some countries will only exacerbate these problems. With uranium reserves limited or largely accessible only at disproportionate cost, concerted expansion strategies will soon require a permanent switch to plutonium - with reprocessing plants everywhere and fast breeder technology the reactor standard. This development strategy would knock today's problems up to a higher dimension. It would multiply the amount of highly radioactive waste that requires permanent disposal. The search for final spent-fuel repositories would also have to be broadened to include more sites with higher total volumes.
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