Hostname: page-component-7b7567c8c-kwt9d Total loading time: 0 Render date: 2026-11-13T23:03:59.222Z Has data issue: false hasContentIssue false

Diffusion of Plutonium in Compacted, Brine-Saturated Bentonite

Published online by Cambridge University Press:  26 February 2011

E. J. Nowak*
Affiliation:
Sandia National Laboratories Albuquerque, New Mexico 87185 USA
Get access

Abstract

Diffusivities were measured for plutonium in brine-saturated compacted Wyoming bentonite. Complexities of the solution chemistry and retardation of transuranics necessitate diffusion studies under conditions that are specific for repository host rock types in this case salt. Diffusivity values in the range of 10−15 to 10−14 m2/s were obtained for bentonite at a packing density of 1800 kg/m3. That density was obtained by compaction at 15 i0Pa, a typical lithostatic pressure in a repository in salt at 650 m depth. Even a 0.05 m (2 inch) thick bentonite-containing engineered barrier could decrease radionuclide release rates by approximately 4 orders-of-magnitude if the diffusivity for that radionuclide were in the observed range of 10−15 to 10−14 m2/s. These results confirm the effectiveness of uncompacted bentonite-containing materials as engineered barriers for radioactive waste isolation.

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable