Would you want to live near a vein of uranium?
Uranium, Depleted Uranium, Enriched Uranium
Uranium is a metallic chemical element with the symbol U and the atomic number 92. It was named after the planet Uranus. It occurs naturally in the mineral pitchblende and many other minerals; particularly uraninite. Its distribution around the world is fairly uniform. It is radioactive, and isotope 235U is used for nuclear reactors and nuclear weapons. Uranium is toxic, but 235U is found in small amounts in animals, plants, water, rocks and soil without harm. Refined uranium is very dense, but it is not strongly radioactive. In contact with the air it gains a coat of uranium oxide.
235U is the only fissile isotope that occurs naturally; 238U is formed by bombarding 232Thorium with neutrons. 238U is also used to make plutonium for nuclear weapons; 239Pu. Uranium was used in the Manhattan Project and on the bomb that was dropped on Hiroshima. The later bombs used plutonium.
239Pu is usually manufactured in nuclear reactors by exposing 238U to neutron radiation which turns some of it into 239U; two beta decays soon produce 239Pu. The 239Pu and the remaining 238U and any other isotopes of other elements are then separated chemically. Reactor-grade plutonium contains at most 80% 239Pu. Whilst a commercial reactor using unenriched uranium can be used to produce uranium, most need to shut down for weeks to change fuel elements, and unsuitable mixes of the isotopes are produced. Such reactors may be shut down more frequently, or have mechanisms for swapping 238U slugs frequently, so the IAEA inspects them frequently. The RBMK and CANDU types of commercial processor can refuel without shutdowns. In designs which cater for refueling like this, it is not possible to fully contain the reactor, which led to the Chernobyl accident being far worse than it might otherwise have been. Canadian Candu nuclear power reactors use natural unenriched uranium.
Uranium has been used to add a yellow or green tint to glass and ceramic glazes. It is also used for radiometric dating and some chemical uses. Phosphate fertilizers may be contaminated with natural uranium.
Understandably, countries keep tight control over their uranium mines and reserves.
Uranium ores emit radon gas, making mining hazardous.
Concentrated uranium from mines is called yellowcake, as it used to be yellow with a cake-like consistency. With modern methods it tends to be green or black. It is mostly uranium oxide (U308).
Depleted Uranium
Depleted Uranium is almost entirely 238U, with only a little 235U. It is very dense, so some militaries used it to shield tanks and for bullets, missiles and other penetrating weapons. It may also be used as counterweights in helicopters and airplanes.
Enriched Uranium
Enriched Uranium has a higher proportion of 235U than normal. It is used to power nuclear ships and submarines. It is also used in nuclear weapons. Most commercial nuclear power plants are only slightly enriched.
Texas Family Fights Uranium Mining
The U.S. Environmental Protection Administration has condemned the water that five generations of an extended family has been drinking because of high uranium levels. They are told that it is natural seepage from a vein of uranium that runs near their well. They believe that it is due to the mining that has been carried out nearby for the past 20 years, and want it stopped.
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