Uranium is a heavy silvery-white radioactive metallic chemical element that occurs in nature and is used as a fuel in nuclear reactors and weapons. Uranium is found in trace quantities around the world, but in only a few places is it found in concentrated deposits or ores. The world’s richest deposits are found in Saskatchewan, (Canada), Australia and in parts of Africa. Uranium occurs in nature as a blend of three similar types, or isotopes. The most common type of uranium found in natural deposits is U-238, which makes up 99.27%. The rest is a mix of U-235 (0.72%) and U-234 (trace quantities). Most atomic power stations use enriched uranium, where the more useful (fissionable) U-235 atoms are concentrated to make up a larger proportion of the mix. Even the highest grade deposits contain less than 1% uranium. So huge amounts of ore have to be processed to get useful quantities of the uranium. Uranium isotopes are radioactive. The nuclei of radioactive elements are unstable, meaning they are transformed into other elements, typically by emitting particles (and sometimes by absorbing particles). This process, known as radioactive decay, generally results in the emission of alpha or beta particles from the nucleus. It is often also accompanied by emission of gamma radiation, which is electromagnetic radiation, like X-rays. These three kinds of radiation have very different properties in some respects but are all ionizing radiation — each is energetic enough to break chemical bonds, thereby possessing the ability to damage or destroy living cells.
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How is Uranium produced?
Crushing : Uranium ore is either dug out of the ground or the uranium is leached from the ore in the mine. Typically these mines are built to last only about 15 years. Drilling and blasting are used in either open pit (strip-mining) or underground mines. Because uranium is generally found in such low concentrations, huge amounts of rock must be mined. For every one tonne of uranium ore produced, there are 55 tonnes of waste radioactive rock produced. The uranium content of the ore is often between only 0.1 percent and 0.2 percent. Before the uranium metal is extracted, the ore must be crushed into finer and finer fragments. After primary crushing, the ore is passed into a rotating ball mill, which grinds the rock into a fine powder. This powder is then treated to remove the uranium. The powder left over from the extraction of the uranium is called tailings. The minute size of these particles makes it impossible to keep them completely isolated from workers and the surrounding environment. In addition, the release of decay products of uranium into the biosphere is greatly accelerated.
Milling : The ore is typically milled near the mine to reduce transportation costs. Huge amounts of water and chemicals are added to the pulverized ore. The uranium chemically bonds with a strong acid (sulfuric acid) or a strong base (caustic soda, also called sodium hydroxide) and, through a series of steps, about 90 percent of the uranium is separated from the host rock.
Refining : The last stage of drying, separating (centrifuging) and chemical precipitation, results in a product called Yellow Cake, which is a yellow to brown powder that contains 90 percent uranium oxide (U3O8). Once it is milled into yellowcake (U3O8), uranium is then sent to be processed into Nuclear Fuel.
Uranium ore usually contains only a small percentage of pure uranium. As long as it remains outside the body, lower grades of this ore pose little health risk. However, if uranium is inhaled or ingested, its radioactivity can trigger the development of lung cancer and bone cancer. Uranium at low concentrations is also chemically toxic and can cause damage to internal organs, notably the kidneys. Animal studies suggest that uranium may affect reproduction and the developing foetus. Its carcinogenic nature increases the risk of leukemia and soft tissue cancers, such as bowel cancer. It can cause changes in the DNA genetic code and/or chromosomal damage.
What are the Problems with Uranium Mining?
1. Tailings Waste Tailings are the left-over sludge after the uranium metal is extracted from the uranium ore and are dumped into manmade lakes, also called tailing ponds. The half-lives of the principal radioactive components of mill tailings, Thorium-230 and Radium-226 are long, 75,000 and 1,600 years respectively. These tailings are pumped into tailing ponds and covered with water to reduce radioactive emissions In addition to the radioactive hazards, tailings may contain chemically hazardous substances including cyanide, arsenic, lead and mercury, which are able to get into the environment by seepage, leaching and blown dust. Uranium tailings can retain as much as 85 percent or more of the original radiological elements. Tailings is almost as radioactive as the uranium itself and some of it may remain hazardous for more than 250,000 years, which might as well be forever causing cancer.
2. Radon Gas As uranium emits radiation, it transforms itself into a new element, which in turn emits radiation and decays, and goes through 14 steps until it eventually – after hundreds of thousands of years – becomes a stable form of non-radioactive lead. One of the elements along the way is radon, a radioactive gas that can travel for hundreds of kilometers before decaying. Mine workers and others who breathe in this gas risk developing lung cancer and other forms of lung disease.
3. Environmental Contamination Uranium mining contaminates the air, water and earth with radioactive chemicals and heavy metals that can never be properly cleaned up. In addition to the radiation hazard, mining is also associated with poisonous process chemicals, heavy metals and the use of huge quantities of water. In the short term, uranium mine sites wreck the ecology of the local region; in the long term, they pose a risk to a much broader area.
4. Health risks The health risks of uranium mining are by now quite well known, although still aggressively disputed by the mining industry. Collectively, uranium miners suffer the highest radiation doses of all workers in the nuclear fuel chain (apart from accident cleanup crews). The main problems are inhalation of dust and radon gas, which leave alpha radiation emitters lodged in the body where they can do most harm. As the contamination from the mines spread away from the minesite, local people are also exposed to contamination. While uranium mining is most commonly associated with cancer, low level radiation is also implicated in birth defects, high infant mortality and chronic lung, eye, skin and reproductive illnesses.
5. Nuclear Waste There is a massive amount of high level nuclear waste still being spewed out by reactors around the world and there is nowhere safe to put it. Nuclear power stations create this waste as part of normal operations, but there are also risks of reactor accidents. The most well known of these accidents have been at Chernobyl in erstwhile Soviet Union ( now Ukraine) and Three Mile Island, USA. The explosion at Chernobyl in 1986 killed many people, spread nuclear pollution right around the planet and forced the permanent evacuation of the surrounding area.
6. Nuclear Weapons While the Government of India does not like to admit it, nuclear power is a military technology designed to produce plutonium for nuclear weapons. Isn’t it shocking that the Indian government spends 14% of its budget on military related spending whereas less than 3% is spent on health and education!
Is Uranium Exploration dangerous?
Before mining uranium, exploration or looking for uranium needs to be carried out. This is done to find out where exactly the uranium is located in high deposits and to also determine its quality. This kind of exploration of uranium can also cause health risks to communities, especially those that already have high background levels of radiation. Taking rock samples can disturb uranium ore and release uranium into the biosphere. Once exposed to air and moisture, the composition changes – radioactive dust particles can spread by water and air. When drilling occurs, the exploration may disturb underground uranium deposits, which then can leach out into underground water reservoirs, potentially contaminating drinking water aquifers. Exploration of Uranium in West Khasi Hills ( Domiasiat) has also indicated its dangerous and negative impact on health.
Is it only in Meghalaya that people are not allowing Uranium Mining?
Meghalaya is just one of the places in the world where there is opposition to uranium mining. People around the world have organized to stop uranium exploration and mining. In many such countries even the governments agree with the people and have put a ban on uranium exploration and mining. Canada and Australia have the highest deposits of Uranium, but states in these countries have independently decided not to allow mining of uranium to safeguard their land and people. On February 27, 1980, the British Columbia Minister of Mines d announced a seven-year moratorium on the recording of mineral claims for the purpose of uranium exploration and the development of uranium deposits on existing claims. The moratorium expired in 1987, but was again renewed. On April 8, 2008, the Nunatsiavut Government imposed a 3-year moratorium on uranium mining on Labrador Inuit Lands. Nova Scotia has had a moratorium on uranium exploration and mining since 1982. If a company finds uranium in concentrations greater than 100 parts per million, it must report those results and stop digging. The Western Australia state government policy prohibits uranium mining. The South Australia state government has a “no new uranium mines” policy. The Queensland state government policy prohibits uranium mining. In New South Wales, the Uranium Mining and Nuclear Facilities (Prohibitions) Act 1986 prohibits prospecting or mining for uranium. In Victoria the Nuclear Activities (Prohibitions) Act 1983 prohibits exploration and mining for uranium. In USA, Uranium mining has been barred in Virginia by a 25-year-old moratorium. Greenland doesn’t allow any uranium mining or prospecting to take place on the island.
How safe is Nuclear Power?
To say that Nuclear Power is a safe method for power generation is a lie. Nuclear energy is fraught with dangers at every step right from mining, transportation, storage, utilization and management of the end product. The radiation related diseases in the population around Uranium mines and Nuclear facilities are well known. There is no fool proof method to safeguard the nuclear facilities. India has poor track record in this matter. According to reports an estimated 300 incidents of a serious nature have occurred at Indian Nuclear Facilities, causing radiation leaks and physical damage to workers, but these have remained official secrets. According to the studies conducted by International Physicians for the Prevention of Nuclear War (IPPNW) and German Society for Radiation Protection (IPPNW/GfS) in the region around Chernobyl in Ukraine after the Nuclear Accident, found that 50,000 to 100,000 liquidators (clean-up workers) died in the years up to 2006. Between 540,000 and 900,000 liquidators have become invalids and disabled.12,000 and 83,000 children were born with congenital deformations. These dangers were once again made clear in a recent study published in July 2007 in the European Journal of Cancer Care (2007, 16, 355363), that showed that there is up to 24% rise in Leukemia in children around nuclear facilities in Canada, France, Germany, UK, Japan, Spain and the US. Can we afford to sacrifice human resource at the cost of power generation?
How safe is Nuclear Waste ?
Till date there is no method with which we can dump the nuclear waste safely. There have been complaints that workers at the uranium mines and the extraction plant in Jaduguda in the state of Jharkhand, and the Nuclear Fuel Complex in Hyderabad—which churns out 50,000 tons of contaminated waste product every day—are not adequately protected from radiation intake and external exposure. Several studies conducted in these areas point to radiation related diseases in the local population.
Isn’t Nuclear energy a cheap way of producing Electricity?
Government claims that nuclear power will add 20000 Megawatts in the next 20 years to the power generation. But the estimates based on previous experience show that it may not lead to more than 5000 to 7000 MW generation. In the year 1998 instead of an installed capacity of 2180 MW from the nuclear power plants, we were getting less than 872 actual MW of power. That means our nuclear plants were generating less than 40% of their installed capacity. India has already invested more than Rs.80000 crores on these nuclear power plants. At present, 25 percent of our energy budget goes to the Department of Atomic Energy (DAE), which accounts for far less than 3 per cent of total power produced in our country. To build 20000.00 MW of nuclear capacity in the next two decades India will have to spend Rs.10000.00 crores every year for 20 years which means a total of Rs.200,000 crores. If you compare Nuclear power to other sources of energy then you realize that Nuclear power is one of the most expensive sources of energy.The cost of building a power plant based on Coal comes out to be around Rs. 4.5 crores per MW. Like wise combined cycle gas turbines that run on gas or Naptha cost around Rs. 3.00 crores per MW. But the cost involved in producing power from nuclear energy is around Rs.10.00 crores Per MW i.e double the cost from fossil fuel and triple the cost from gas.
But are there any alternatives?
It is incorrect to say that there are no other alternatives. That the Thermal plants add to green house effect is an acceptable argument but electricity generation accounts for only 9 percent of global Green House Gas (GHG) emissions. Emission from cars and other forms of transportation is much higher. That nuclear plants involve no fossil fuel is untrue. Each step in the “nuclear fuel cycle”, from uranium mining to reprocessing, emits GHGs. Nuclear power isn’t hugely superior to gas or coal as regards GHG emissions. It’s certainly inferior to renewables like wind and solar. India has ample potential for renewable resources of energy, which are hazard free, much cheaper, transparent, do not require any security and are much easy to be installed. For example the total gross potential of wind power in our country is over 45000 Megawatts out of which we are using only 2900 MWs. Solar and biomass energy potentials have not been fully explored even though they are in abundance. Small Hydro power plants have a potential of about 15000 MWs. Similarly biomass power has a potential of 19000 MWs and urban and industrial waste of 1700 MWs. Besides this India receives solar energy equivalent to over 5000 trillion kWh/year, which is far more than the total energy consumption of the country. Let us divert our budget to Research and Development in renewable energy sources. These promise us a cleaner and safer environment and guarantee us our life!