Uranium Basics
Uranium is a naturally occurring, very heavy metal. One of the heaviest elements on the periodic table, it holds the symbol “U.” Natural uranium (U3O8) occurs in the earth’s crust as commonly as tin or zinc. The sandy, yellowish substance called yellowcake, the commodity uranium-mining companies produce, is the form natural uranium takes when extracted from ore.
Yellowcake, the commodity uranium-mining companies produce
Natural uranium is nearly everywhere. It is present in most rock and in seawater, and very small concentrations of it may be found in food and human tissues. A square mile of earth about 1 foot deep typically contains about two tons of uranium. Concentrations large enough to be of economic interest at prevailing uranium prices, however, occur only in hard rock and sandstone.
It is advisable to take the same safety precautions with yellowcake which one would take with lead. Like many cleaning fluids commonly kept beneath kitchen sinks, it is harmful only if ingested. Yellowcake neither burns nor blows up, which makes it useless in the hands of terrorists and far safer to transport than common fuels like gas and propane. Yellowcake, or natural uranium, has very little radioactivity; it only emits alpha particles, a form of radiation which penetrates neither human skin nor clothing. The daughter products of natural uranium—radium, thorium, and radon gas; which occur alongside uranium in nature—produce 85% of the radiation generally associated with uranium, but these products are removed during the mining and milling process and are therefore absent from yellowcake.
The production of yellowcake is but the first of many stages in the nuclear fuel cycle, the process of turning uranium ore into electricity for America’s vast nuclear defense fleet and 104 reactors. Without fuel made from yellowcake, there is no nuclear power.
Uranium is used primarily to generate electricity in nuclear reactors, and uranium is a significant fuel source for Virginia and for the whole nation. Dominion Power’s four reactors in Virginia—two at North Anna and two at Surry—produce nearly forty percent of Virginia’s electricity, and the reactors consume roughly 1.6 million pounds of uranium per year. In 2010, nuclear power was the largest source of electricity in the Commonwealth. On the national level, 20 percent of U.S. electricity is generated by 104 nuclear reactors, and it takes about 55 million pounds of uranium to fuel those reactors each year.
Although nearly all of the uranium produced the world over is used to generate electricity in nuclear reactors, other uses of uranium are worth noting. Throughout the 1800s, uranium gave vases and other household items fashioned of glass a green-yellow hue. It has, of course, been processed for nuclear weapons. Presently, however, it is more commonly used for ship anchors and military vehicle armor because of its extremely high density. Another prominent modern use for uranium is nuclear medicine; it is fissioned in reactors to produce radioactive isotopes, which are then used to develop diagnostic images, as well as to treat thyroid cancer and blood disorders.