Radioactive waste also plays a significant role. Uranium tailings are waste by-product materials left over from the rough processing of uranium-bearing ore. They are not significantly radioactive. Mill tailings are sometimes referred to as 11(e)2 wastes, from the section of the Atomic Energy Act of 1946 that defines them. Uranium mill tailings typically also contain chemically hazardous heavy metal such as lead and arsenic. Vast mounds of uranium mill tailings are left at many old mining sites, especially in Colorado, New Mexico, and Utah. Although mill tailings are not very radioactive, they have long half-lives. Mill tailings often contain radium, thorium and
Uranium metallurgy to any appreciable extent that is fissile, that is, fissionable by thermal neutrons. The isotope U is also important because it absorbs neutrons to produce a radioactive isotope that subsequently decays to the isotope 239Pu (plutonium), which also is fissile. Uranium in its natural state comprises just 0.71% U and 99.3% U, and the main focus of uranium metallurgy is the enrichment of uranium through isotope separation. Uranium metallurgy In materials science and materials engineering, uranium metallurgy is the study of the physical and chemical behavior of uranium and its alloys. Commercial-grade uranium can be produced through the reduction of