Nuclear materials contain a great variety of isotopes, elements, chemical compounds, and mixtures. Definitions are important because substances are managed by law and regulation according to classification. Radioactive materials fall into several categories according to their origin, the type of material present, and their level of radioactivity. There are two distinctions of radioactive waste: Defense waste and Commercial waste.
Defense wastes are those that have been produced since the beginning of World War II. They are the result of plutonium production, and spent fuel from nuclear propulsion reactors. On the other hand, commercial wastes are those produced by reactors used for electrical power, by facilities used to process reactor fuels, and by a variety of institutions and industries. Both defense and commercial reactor wastes stem from the operation of fission reactors, but defense wastes generally are considerably older and less radioactive.
There are three important types of radioactive waste :
