The Environmental, Social and Ethical Consequences of mining,
processing and using Uranium
Uranium, an element of the chromium group, never occurs naturally in a free state, although through processes of extraction it can be obtained from rare complex minerals such as pitchblende, carnotite, and uranite. Unfortunately, mining and using Uranium has become an issue that the world must tackle. At every stage of Uranium’s life, problems arise and damage our world, whether it is in an environmental, social or ethical sense.
Before the uranium can be used it has to be mined. Pitchblende, a dark mineral that is the chief source of uranium, is “taken from the earth like any other metal, blasted and dug” from open-pit mining, surface mining and underground mining. Although, the creation of the mines causes great environmental damage because they not only destroy natural landscapes, they also drive people and other organisms from their habitats. Also the uranium mines and their processing operations in nuclear reactors produce sandy wastes called tailings. These contain several radioactive elements, including thorium, radium, and radon, which emit low levels of radiation. This increases radiation risks to the workers, and environmental contamination.
To obtain uranium, pitchblende goes through complex milling processes so that in the end it can be sold to nuclear reactors, in a form known as yellow cake (with the chemical symbol U3O8). First, pitchblende is grinded in small grains to increase its surface area, preparing it for the leaching process where it will be treated with strong acids. Then water is added to make it easier for the pitchblende to be transported by pumps to where the leaching process with take place. The water molecules are then driven away by heated, and the little pieces of pitchblende are exposed to strong acids, for instance sulfuric and nitric acids. All the uranium in pitchblende dissolves, forming uranyl sulfate (UO2SO4); sulfates containing others metals such as radium that also helped to form pitchblende ore are precipitated. Then sodium hydroxide is added and uranium is precipitated as sodium diuranate, which is also known as the yellow oxide of uranium and it has the chemical formula of Na2U2O7 · 6H2O. Uranium can also be obtained from carnotite, and to do so the ore is ground into a fine powder and is added to caustic soda and potash, thus dissolving out uranium, vanadium and radium. After the worthless sandy wastes are washed away, the solution is treated with barium chloride and sulfuric acid. Then a caustic alkali solution is added to the clear liquid which was left behind, which precipitates the radium and, more importantly, the uranium in concentrated form.
