in situ method for remediating 137Cs-contaminated wetlands
using naturally occurring minerals
G. Hinton1, A. Knox1, D. Kaplan2, and
1Savannah River Ecology Laboratory, Drawer
E, Aiken, SC 29802, USA
Savannah River Company, Aiken, SC, USA
Cesium's enhanced bioavailability in contaminated wetlands on
the U.S. Department of Energy's Savannah River Site (SRS) is thought to
to the low clay fraction of SRS soils, and that the
clay mineralogy is dominated by kaolinites.
Remediation of the wetlands is problematic because
current technologies are destructive to the sensitive ecosystems.
We tested 11 clay minerals (two micas, a vermiculite, six illites,
a kaolinite, and a smectite) for their propensity to sorb
and retain 137Cs. Two minerals were subsequently chosen as
candidates for in situ remediation amendment materials because
they had 137Cs distribution coefficients (Kd) well
in excess of 10,000 ml·g-1, and desorbed less than 20%
of the Cs when mixed in a 0.1 M NH4Cl solution.
Incremental additions of the candidate minerals to 137Cs-contaminated
sediments appreciably intercepted and retained desorbed 137Cs
in the presence of high levels of NH4. Implications for using
the minerals as a nondestructive, in situ remediation technique are discussed.
Hinton, T. G., K. A., D. Kaplan, and S. Serkiz. 2001.
An in situ method of remediating 137Cs-contaminated wetlands using naturally
occurring minerals. Journal of Radioanalytical and Nuclear Chemistry 249:197-202.
To request a reprint