| In the United States, uranium (U) mining is controversial, and with Wyoming being the nation's largest producer of U, it is important to be prepared for handling soils on U mines that have been impacted by leaks and surface spills during in-situ recovery (ISR) of U. Methods for remediating contaminated soils are warranted for economic, environmental, and public relations reasons. While U is removed in the mining process, radium (Ra) contamination is of concern when leaks or spills occur. Contaminated soils are often removed for off-site disposal at Nuclear Regulatory Commission (NRC)-approved facilities, which can be expensive and involves risk in transporting radioactive material along public highways. A two-phase study was conducted to establish whether there are feasible alternatives to removal and disposal and whether 5 cm depth samples rather than the standard 15 cm depth samples can be taken from surface soil in event of a spill. Potentially feasible alternative strategies include dry sorting, soil washing, homogenization and phytoremediation. Of a total of 47 soil samples taken in September and November, 2011, one sample showed a high 226Ra activity of 5.7 pCi g-1, which did not exceed regulatory standards. Results did not support removing the top 5 cm depth as opposed to the top 15 cm depth when dealing with spills. |
