at Georgia State University
Clay Mineralogy of Rife Integrated Challenge Site:
The Rifle Integrated Challenge Site is the site of a former Uranium processing plant adjacent to the Colorado River. It is now being studied under funding from the US DOE to find best ways to clean up the uranium and related minerals from these alluvial/floodplain sediments. The clay mineralogy is important in sorbing metals in these sediments through ion exchange and/or other sorption mechanisms. A set of samples were collected down core and were sent to GSU to identify the clays in these sediments.
These samples were treated to remove carbonate, organic matter and iron (III) oxides following well known methods of Jackson (1985). The clay fractions were separated using timed settling. The clay fraction (< 2 micron fraction) was mounted on petrographic glass slides to identify the minerals using X-ray diffraction. We also prepared oriented mounts that were saturated in potassium using the Millipore filter technique. We used the new XRD in Geosciences to identify these minerals. A representative diffraction pattern is shown below. Three students helped with this project (Rebecca Pickering, David Lims and Laura Zaunbrecher). This study was funded via contracts from Battelle Memorial Institute and Lawrence Berkeley Laboratory.