Effect of Extent of Natural Subsurface Bioreduction on Fe-mineralogy of Subsurface Sediments
Naturally bioreduced zones with considerable sorbed U were recently identified
at a former U mining and processing site at Rifle, CO, USA. Most of the sorbed U appears to be associated with Fe minerals. Variably reduced sediment samples were analyzed by suite of techniques, primarily by room temperature Mössbauer spectroscopy. Fe-oxides of different types and crystallinity, and Fe(II)/Fe(III)-containing clays are dominant in all the sediments. The amounts of poorly crystalline Fe(III)-oxide, however, was lower in the reduced samples. In addition, framboidal pyrites with sorbed U were common in the highly reduced sediments. Overall, the information gained from this work may help develop design field strategies for
immobilization and stabilization of U(VI) in contaminated subsurface environments.
Revised: May 17, 2010 |
Published: May 16, 2010
Kukkadapu R.K., N. Qafoku, B.W. Arey, C.T. Resch, and P.E. Long. 2010.Effect of Extent of Natural Subsurface Bioreduction on Fe-mineralogy of Subsurface Sediments.Journal of Physics: Conference Series 217, no. 1:012047 1-8.PNNL-SA-69002.doi:10.1088/1742-6596/217/1/012047