Timeline November 1978

The Uranium Mill Tailings Radiation Control Act was passed in 1978 and directs DOE to stabilize and control uranium mill tailings at inactive milling sites and vicinity properties. DOE formed the Uranium Mill Tailings Remedial Action (UMTRA) Project to organize its compliance with the Act.

Since the 1940's, uranium ore has been mined in significant quantities in the United States. At first, private companies mined the ore for the federal government to use in national defense programs. After the 1950's, uranium was also needed as fuel for nuclear power plants to produce electricity. Tailings are the sand-like material remaining after uranium has been extracted from the ore at a uranium mill. Tailings contain residual uranium and radium and many other materials, including arsenic, nickel, iron, molybdenum, copper, thorium, radon gas, and all the other elements in the uranium decay chain. The Act directs DOE to clean up not only the milling sites but also vicinity properties. These properties are residences, commercial structures, or open lands where tailings were used as construction materials before their potentially harmful effects were recognized.