Impact of natural organic matter on U speciation and mobility in groundwater
EMSL Project ID
48747
Abstract
Uranium (U) contamination of aquifers is a persistent problem at DOE legacy ore processing sites and, contrary to initial predictions, many plumes are not attenuating with natural groundwater flushing. In these sediments, U is typically enriched in organic-rich fine-grained lenses of sediment that are interspersed with the coarser aquifer material. Natural organic matter (NOM) plays an important role in retention and redox transformations of U in these sediments. The scientific focus of the proposed work is to identify key characteristics of NOM that are likely to be important to U biogeochemistry within the U-enriched zones to constrain the mechanisms controlling U mobility in aquifers. We propose (i) to examine how NOM chemistry influences U speciation through complexation in laboratory batch reactor systems and aquifer sediments, using nano-scale secondary ion mass spectrometry (NanoSIMS) coupled with sub-micron synchrotron-based x-ray microscopy measurements. We further propose (ii) to determine functional group abundances, molecular size and composition in NOM from reactor systems and U-rich zones within aquifer sediments using high-resolution Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS) in combination with a suite of solid- and liquid-state nuclear magnetic resonance (NMR) techniques.
Project Details
Project type
Exploratory Research
Start Date
2015-03-11
End Date
2015-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)
Team Members
Related Publications
Bone, S.E., Cliff, J., Weaver, K., Takacs, C.J., Roycroft, S., Fendorf, S. and Bargar, J.R., 2019. Complexation by organic matter controls uranium mobility in anoxic sediments. Environmental Science & Technology, 54(3), pp.1493-1502.
Bone, S.E., Dynes, J.J., Cliff, J. and Bargar, J.R., 2017. Uranium (IV) adsorption by natural organic matter in anoxic sediments. Proceedings of the National Academy of Sciences, 114(4), pp.711-716.
Boye KE, VS Noel, MM Tfaily, WL Dam, JR Bargar, and S Fendorf. 2016. "Carbon Characteristics and Biogeochemical Processes of Uranium Accumulating Organic Matter Rich Sediments in the Upper Colorado River Basin ." Abstract submitted to American Geophysical Union Fall Meeting 2015, San Francisco, CA. PNNL-SA-116123.
Boye, K., Noël, V., Cardarelli, E., Tfaily, M., Bargar, J.R., Fendorf, S. (2015) Carbon Characteristics and Biogeochemical Processes of Uranium Accumulating Organic Matter Rich Sediments in the Upper Colorado River Basin. LCLS/SSRL Annual Users Meeting, Menlo Park, Oct 7-10. [Invited]
Boye, K., Noël, V., Cardarelli, E., Tfaily, M.M., Dam, W.L., Bargar, J.R., Fendorf, S. (2016) Imprints of thermodynamic constraints on microbial carbon oxidation in floodplains. Goldschmidt, Yokohama, Jun 26-Jul 1. [Oral]
Boye, K., Noël, V. Tfaily, M. Bone, S., Bargar, J.R., Fendorf, S. (2015). Organic matter chemistry in floodplain soils and sediments ? implications for uranium retention. SSSA Annual Meeting, Minneapolis, MN. Nov 18. [oral]
Noël V, Boye K, Kukkadapu R., Bargar J.R. (2018) Coupled hydrology-redox controls over U mobility in shallow contaminated sediments. International conference Uranium biogeochemistry CSF ? Monte Verita Ascona, Switzerland [Talk]
Noel V, KE Boye, RK Kukkadapu, SE Bone, JS Lezama Pacheco, E Cardarelli, N Janot, S Fendorf, KH Williams, and J Bargar. 2017. "Understanding the controls on redox processes in floodplain sediments of the Upper Colorado River Basin." Science of the Total Environment 603-604:663-675. doi:10.1016/j.scitotenv.2017.01.109