Large-Scale Physical Separation of Depleted Uranium from Soil
ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS ENVIRONMENTAL LAB
Pagination or Media Count:
Dry physical separation processes were tested at large-pilot scale 1,000 kg soil batches at Yuma Proving Ground YPG to evaluate this technique for removal of depleted uranium DU metal from soil. Two sample locations, the Catch Box and the Buried DU Penetrator Test Site DU Garden were evaluated. These locations were chosen since previous small-scale testing confirmed that soils from these sites had varied uranium concentration, degrees of weathering, and aging of fired DU munition residues. Vibratory soil screening dry sieve separation was found to be effective for DU metal removal from Catch Box sand of YPG. On average, 50 of the mass of DU was removed with a single dry sieve separation of the Catch Box sand. The soil fines still contained DU, so control of fugitive dust emissions may be required. The degree of DU fragment weathering was found to be important to the success of the physical separation technology. The penetrator rod excavated from the DU Garden was highly weathered resulting in ineffective physical separation. The lesser degree of weathering of DU fragments in the Catch Box soil made successful physical separation possible. The difference in weathering of DU in the DU Garden versus the Catch Box could be due to increased exposure time 4 to 7 years in the garden versus approximately 18 months in the Catch Box, differences in soil chemistry the DU garden was a desert soil, the Catch Box construction grade sand, andor better aqueous drainage in the sandy Catch Box media. Non-uranium metals concentration were also increased in the DU Garden compared to both background soil concentrations and the concentrations detected in the Catch Box sands. Results indicate that periodic screening of Catch Box soils, coupled with dust control measures, could considerably increase the useful lifetime of Catch Box soil.
- Soil Mechanics
- Radioactivity, Radioactive Wastes and Fission Products