Uranium tailings

Uranium tailings are a waste material of uranium mining. In mining, the raw uranium ore is brought to the surface and crushed into a fine sand. The valuable uranium-bearing minerals are then mechanically removed, and the remaining radioactive sand, called "uranium tailings", is stored in huge impoundments.

If these uranium tailings are left on the surface and allowed to dry out, the radioactive sand can be carried great distances by the wind, entering the food chain and bodies of water.

Uranium tailings contain over a dozen radioactive nuclides which are all harmful to living things. The most important of these are thorium-230, radium-226, radon-222 (radon gas) and the daughter isotopes of radon decay, including polonium-210.