Between 100 million and 280 million tons of phosphogypsum waste are estimated to be produced annually as a consequence of the processing of phosphate rock for the production of phosphate fertilizers. In addition to being useless and abundant, phosphogypsum is radioactive due to the presence of naturally occurring uranium and thorium, and their daughter isotopes. Depending on the price achievable on the uranium market, extraction of the uranium content may be economically lucrative even absent other incentives, such as reducing the harm the radioactive heavy metals do to the environment.