Uranium recovery

Uranium recovery is the extraction or concentration of uranium from any ore processed primarily for its source material content. Similarly, thorium was also extracted or processed in the past. The uranium recovery processes result in wastes that typically contain relatively low concentrations of radio­active materials having long half-lives. The wastes, in both solid and liquid forms, are classified as 11e(2) byproduct material in accordance with AEA definitions (see Table 18.3).

Three types of uranium recovery facilities have operated, are currently operating, or are planned to operate in the future within the United States: conventional mills, heap leach facilities, and in-situ recovery facilities. Con­ventional mills and heap leach facilities extract uranium from ore processed above ground and, consequently, generate large volumes of solid 11e(2) byproduct material. This material is disposed of in licensed near-surface impoundment(s) on the site of the processing facility or in an offsite waste disposal facility licensed to accept 11e(2) byproduct material. In-situ recov­ery facilities differ from the others in that they leach uranium from ore bodies in the subsurface. Consequently, the predominant waste stream for in-situ recovery facilities consists of liquid wastes generated during their operation (typically less than 200 megaliters per year). The liquid wastes are disposed of by deep disposal well injection, by evapotranspiration to the atmosphere through land application of partially treated liquid waste, or by evaporation to the atmosphere from man-made lined ponds. The volume of solid waste generated at an in-situ recovery facility (including salts from the evaporation process) is relatively small (typically less than 1000 m3 per year) and is ultimately disposed of offsite at a waste disposal facility licensed to accept 11e.(2) byproduct material.

Prior to the mid-1980s, the sole type of uranium recovery facility in the United States was the conventional mill. Many of those previously operat­ing facilities were reclaimed or are in the process of remediating (decommissioning) waste resulting from extracting uranium. Because of near-surface impoundments, those properties (and heap leach facilities) will be subject to long-term care after closure through government ownership. In-situ recovery facilities do not include onsite disposal impoundments and, thus, do not require long-term care after closure.