Leachability uranium

This easily leachable uranium could have been remobilized during phases P3 and processes. The thermal flow induced by the intrusion of lamprophyres and microgranites could have... 

Hydratable oxides may also be present in NFS from some sources, which could potentially contribute to volumetric instability. Depending on the ore and metallurgical process, nonferrous slags produced from sulfide ores can contain leachable elemental sulfur and heavy metals, which should be investigated prior to use. Sulfurous leachate is primarily of aesthetic concern, resulting in sulfur odor and possible discoloration of water in poor drainage conditions. In addition, phosphate rocks can contain between 30-200 ppm uranium. Most of this uranium is incorporated in the phosphorus slag and results in the release of some radiation (in the form of radon gas). 

Thoria-based fuels are appealing from a wasfe managemenf perspective because Th02 is chemically stable and almost insoluble in groundwater. By far fhe most important chemical difference between Th02 and UO2 is the fact that thorium is present in its maximum oxidation state, Th(IV), whereas uranium is not. Therefore, oxidative dissolution of the matrix is not an issue with thoria fuel. Redox conditions could affect the leachability of 233U from irradiated thoria, but this would be limited to surface dissolution and is unlikely to be a major concern. 

Starik, I. E., Lazarev, K. F. Study of the comparative leachability of the isotopes of radium, uranium, and thorium from monazite. Methody Opredeleniyu Absolyut. Vozrasta Geol. Obrazov., no. 6, 24—31 (1964). 

Smith D. B., Zielinski R. A., and Rose W. I., Jr. (1982) Leachability of uranium and other elements from freshly erupted volcanic ash. J. Volcano Geotheim. Res. 13, 1-30. 

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