 Plutonium has been released into the environment in aqueous solution from nuclear reprocessing and uranium enrichment plants.The chemistry of this plutonium is different from that of the metal oxides formed from nuclear bomb detonations.One example of a site where plutonium entered the soil is Rocky Flats where in the recent past XANES (X-ray spectroscopy) has been used to determine the chemical nature of the plutonium in the soil.