SREL Reprint #2582

Heterogeneous plutonium sorption on Yucca Mountain tuff

M. C. Duff1, M. Newville2, D. B. Hunter1, S. R. Sutton2, I. R. Triay3, D. T. Vaniman4, P. M. Bertsch5,
P. Eng2, and M. L. Rivers2

1Westinghouse Savannah River Company, Savannah River Technology Center, Aiken, SC, USA
2Department of Geophysical Sciences and Center for Advanced Radiation Sources,
The University of Chicago, Chicago, IL, USA
3Waste Isolation Pilot Plant, Carlsbad, NM, USA
4Los Alamos National Laboratory, Los Alamos, NM, USA
5The University of Georgia, Savannah River Ecology Laboratory, Aiken, SC, USA

Abstract: There are many unresolved questions regarding plutonium (Pu) sorption on tuff rock in Yucca Mountain. In this study, we have used synchrotron x-ray microspectroscopy and microimaging techniques to measure the spatial distribution and local structural speciation of sorbed Pu on tuff. The results demonstrate that Pu is sorbed strongly and preferentially to trace levels of manganese oxides and smectite minerals. Additionally, some Pu(V) was oxidized to Pu(Vl) upon sorption, but the sorbed Pu eventually undergoes reduction to Pu(IV).

SREL Reprint #2582

Duff, M. C., M. Newville, D. B. Hunter, S. R. Sutton, I. R. Triay, D. T. Vaniman, P. M. Bertsch, P. Eng, and M. L. Rivers. 2001. Heterogeneous plutonium sorption on Yucca Mountain tuff. pp. 18-21 In: G. K. Shenoy (Ed.). APS Forefront. Argonne National Laboratory, Argonne, IL.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).