A very important read for anyone interested in questions and answers about the Nuclear Fuel Chain. (excerpts below, full document here)
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The beginning of the end
Like other metals uranium is found as ore mineral in rock. However, the actual uranium content in the ore amounts to only 0.5%. Historically, uranium has primarily been
mined underground or in open pit mines. More recently, however, solution-based “leaching” of uranium has gained importance. In the “liquid” process, sulphuric acid or sodium hydroxide is directly channelled into underground reservoirs and the uranium containing solution is pumped to the surface. The most economically important uranium mines are located in Australia, Canada, Kazakhstan, Brazil, India and more recently in Africa. For years, the quantities produced have not always covered the amount of uranium needed worlwide. This shortfall in the uranium market is primarily met through existing stockpiles, old nuclear weapons and reprocessed fuel elements.
Toxic tailings
The production of the yellow uranium concentrate, or “yellowcake”, is done in processing plants near the mines. Sulphuric acid or alkali and large amounts of water are used to dissolve the uranium from the rock. The separation process leaves ever accumulating quantities of remainder rock and rubble – also known as tailings. These tailings3are pumped into reservoirs in spite of containing many health damaging substances such as thorium, radium and heavy metals (including arsenic). The tailings continue to release 85% of their original radioactivity, only decreasing to a less dangerous level over a few hundred thousand years.
Contamination of humans and nature
Radioactive dust is released in both the mining and milling of uranium. If this dust reaches a human body, radioactive material attacks the cells. Uranium miners are therefore exposed to a highly increased risk of cancer. Additionally, in the areas surrounding the mines, cancer rates in the local populations are higher-than-average. Numerous leaks and crevasses in the mine can cause radioactive waste from the tailing basin to enter the water cycle and contaminate ground and drinking water, lakes, rivers and even the air we breathe. The wind blows radioactive dust from the dried tailings all over the landscape. Radon gas will also escape and if is inhaled, it can cause lung cancer. Animals in
the vicinity of Australian mines exhibit significantly increased sterility and mutation rates. Since most uranium mines are located in arid regions, the high water consumption used in the mining also promotes the desertification of these regions.
At the expense of indigenous peoples
The people who are most affected by uranium mining are indigenous peoples including the Native Americans (Navajo, Laguna, Acoma, and other tribes) in North America, the Tuareg in Niger, the Adivasi in India, and the Aboriginal people in Australia. About 70% of the uranium development areas are on indigenous peoples’ lands. Since their way of life is strongly rooted in local ecosystems, the radioactive contamination essentially means the annihilation of their livelihoods and cultures. Again and again ancestral populations have had to move, established communities have been destroyed and traditions have been disrupted. Often, the development of new uranium mines is accomplished through undemocratic processes. For example, the Australian Government has overridden their environmental laws, including their Water Act, along with the law supporting the cultural heritage of indigenous peoples, in order to support the Olympic Dam mining company.
Uranium Weapons
Uranium weapons contains depleted uranium (DU). As a waste product of the uranium enrichment process, DU accrues worldwide in large quantities. Compared with conventional
munitions, using depleted uranium can double the effectiveness of a weapons penetration. Due to its high density, for example, uranium can penetrate steel. The first time depleted uranium munitions were used, was in the 1991 Gulf War. In the Balkan war, in the late 1990‘s, NATO used 12 tons of depleted uranium munitions, and in the Iraq war, up to 165 tons have been fired so far.
Irreversible destruction of the gene pool
U238 is not only a radioactive alpha particle emitter, but also a chemical poison. Even low doses can damage internal organs. Higher concentrations cause heavy metals poisoning.
Frequent miscarriages and genetic defects in newborns after the Kosovo war and in Iraq, are attributed to depleted uranium munitions. The gene pool of the affected population is destroyed forever.
Dust drifts without respect to borders
As of 2007, 18 countries have included depleted uranium munitions in their arsenals: UK, USA, France, Russia, Greece, Turkey, Israel, Saudi Arabia, Bahrain, Egypt, Kuwait, Jordan, Pakistan, Oman, Thailand, China, India and Taiwan. Besides Iraq, depleted uranium weapons were already used in Afghanistan, Kuwait, Palestine, in Lebanon and Kosovo.
The areas contaminated by depleted uranium include production facilities in the US and the UK, weapons testing grounds and storage sites, and, of course, the locations where accidents have occured and where military actions using depleted uranium weapons have taken place. The clouds of dust contaminated with radioactivity are blown by the wind to areas hundreds of miles away from the site of conflict. Dust drifts, which contain the particles of depleted uranium, blow radioactive particles in dust storms to adjacent areas and countries.
Risky residue
Uranium must first be”enriched” in order to be processed into fuel rods for nuclear power generation. This process also creates highly toxic and radioactive residues.
For electricity generation current power plant models need the easily fissionable uranium isotope U235. However, the yellowcake uranium concentrate only contains 0.7% U235, the largest portion comprises of the more stable U238. Therefore, yellowcake, if it is to be suitable for use in a reactor – needs to be “enriched“ to a U235 content of 3% to 5%. The material to be enriched must also be available in gaseous form. Therefore, it is converted from yellowcake to the chemically aggressive and toxic substance, uranium hexafluoride. In a complicated process, the two isotopes of the uranium hexafluoride U235 and U238 are then separated from each other as much as possible. The part with the greater amount of U235 is called enriched uranium, the part with the lower amount of U235 is called depleted uranium (DU). The enriched material is then compressed into pellets in fuel element factories, pooled into fuel rods and then used as fuel in nuclear power stations. The depleted uranium cannot be used for electricity production.
Uranium transports across Europe
For every ton of enriched uranium, at least seven tons of depleted uranium hexafluoride nuclear waste is created. In Europe, most radioactive remains are transported from Western Europe to Russia where, according to the enrichment company Urenco, the recovery of usable uranium is supposed to happen. From an economic perspective, the re-enrichment of the material is much more expensive than to mine for new natural uranium. For companies, it is primarily a convenient way to dispose of nuclear waste. Since 1996, a total of 27,000 tons of uranium waste from the German enrichment plant in Gronau has been sent to Russia. Worldwide, an estimated 1.1 million tons of depleted uranium is stored at enrichment plants.
Hazardous cargo
Radioactive waste producers carry a risk of their storage tanks leaking and potentially releasing radioactive waste into ground and drinking water. In July 2008, at the French
enrichment plant in Tricastin, 30,000 litres of radioactive uranium solution was released from leaking tanks. Another problem is the risk of accidental explosions. According to the German Government, between early 2007 and October 2008, there were over 300 shipments of nuclear materials through Germany, mostly on public streets. These shipments also pass without escort through inner cities. The uranium is transported as gaseous UF6. Upon contact with humidity, a leak of UF6 would release corrosive hydrofluoric acid. Barrels of UH were found outdoors steadily emitting nuclear radiation. In the Tomsk region, where an enrichment plant is located, the local human life expectancy is only 48 years.
With electricity from coal, oil and gas, the energy from most nuclear reactors is produced in a steam generating power plant. However, the heat from nuclear power is not produced by combustion, but rather by fission.
Hot potato
Just under 3% of global energy is generated by 439 nuclear power plants. In nuclear power stations, large amounts of energy are produced by the fission of a uranium nuclei
inside fuel rods. The released neutrons, in turn, generate more fission and set neighboring atoms into motion and a chain reaction is created. If this process is not controlled, it can lead to a meltdown. In the worst scenario, radioactivity can leak uncontrollably. Water is commonly used to control the speed and temperature of the reactions. The resulting heat from the nuclear fission is transferred to the water, thereby creating steam, which drives the turbines, and electricity is generated.
Risk in detail
The most common types of nuclear power plants are light water reactors, where water serves as coolant and particle brake. There are two types: boiling water and pressurised water reactors. In the somewhat simpler constructed boiling water reactor. The same water which surrounds the fuel elements, drives the generators. Especially with this model, severe hydrogen explosions have occured in the german NPPs of Gundremmingen in 1987, Krümmel in 1999 and Brunsbüttel in 2001. In the pressurised water reactor, nuclear fission and
electricity production are separated by two water circuits. But, both types of reactors pose technical risks. There are frequent leaks and cooling problems. This can be very dangerous, if during an emergency shutdown, the emergency systems still have to deal with the cooling of high temperatures. At a new reactor in Harrisburg, Pennsylvania, the cooling systems failed after an emergency shutdown in 1979, which almost resulted in a meltdown. Also, the emergency power supply is very vulnerable in both models. In 2006, at Forsmark in Sweden, half of the power sets shut down. The nuclear power plant employees acted without functioning measurement systems. According to the former heads of the design department, it was only seven minutes away from a meltdown. The NPPs Krümmel and Brunsbüttel, but also Isar 1 and Gundremmingen are very similar in the design to Forsmark. In heavy water reactors, heavy water (D2O) is used for cooling and is very costly to produce. In graphite reactors, graphite is used as a neutron brake. Examples of this type of reactor are the Soviet RBMK reactors. But the most well known is, Chernobyl. A variety of these type of reactors are still in operation in Russia. A special type of graphite reactor, are high-temperature reactors (pebble bed reactors). They work with fuel balls as the neutron brake. This technology, however, has never gone beyond the testing phase. Breeder reactors in addition to electricity production, are simultaneously used to “breed” fuel-grade plutonium, which is then, in turn, used in other power stations. The security risk is considerably higher, because plutonium is much more explosive and hazardous than uranium. With the exception of small research reactors, not a single “fast breeder“ is currently in operation.
The great explosive force of nuclear weapons and the generation of energy in nuclear power plants occur in the same way: atomic nuclei fission and subsequent release of energy.
Human guinea pigs
Research on nuclear fission was motivated by military intentions from the start. In 1942, in the U.S. the construction of the atomic bomb began under the leadership of the physicist
Robert Oppenheimer, in the top secret “Manhattan Project”. The first nuclear weapon was tested in July 1945 in Alamogordo in the desert of New Mexico. The bombings of Hiroshima and Nagasaki followed shortly afterwards, instantly killing 225,000, and killing and maiming thousands more over the following years. According to information from the International Physicians fort the Prevention of Nuclear War (IPPNW), up to 1998, there were 2058 nuclear tests in numerous locations. To quantify that, between 1945 and 1998, every ten days a test took place. There were 500 nuclear bombs ignited above ground, in the atmosphere, under water or on the Earth. Approximately three times as many tests took place underground after the signing of the Partial Test Ban Treaty in 1963. The tests were conducted primarily in the Pacific Islands, Nevada (USA), Kazakhstan, Russia and China.
Uncontrolled chain reaction
The explosive energy of nuclear weapons is produced by the splitting of atomic nuclei. When a neutron hit a fissionable nucleus, it decays, releasing large amounts of energy.
A chain reaction is set in motion. As a result of nuclear weapons testing, scientists hopes to gain information on pressure waves, temperature, amount of radiation and the potential direction of the radioactive cloud.
Deadly rain
After the detonation of an atomic bomb, there is a release of so-called “nuclear fallout”, an intensely radioactive material. The larger radioactive particles fall down immediately after the explosion and leave a fatal amount of radiation on the ground. Smaller radioactive particles are later thrown into the air. They travel, over large distances, and contaminate soil, air and food products. These particles can cause the symptoms of acute radiation sickness: dizziness, vomiting, cramps, diarrhea, fever, bleeding from mucous membranes, and loss of hair, all of which normally lead to death within a short time. Local weather conditions determine the nature of the fallout. After the atomic bombs on Hiroshima and Nagasaki. Black rain fell. A dark, thick, oily precipitation, full of radioactivity. In the Marshall Islands, radioactive ash rained down, which the inhabitants of the Marshall Islands thought was a kind of “snow”. Local explosion, global radiation As a result of the nuclear tests, the global exposure is greatly increased. This has led, and will continue to lead in the future, to a reduction in human health. An IPPNW study has looked at 430,000 fatal cancers worldwide, which are thought to be as a direct result of the long-term consequences of nuclear testing. Radiobiologists at the University of Munich, Germany, estimate this number could even be as high as three million.
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