Caustic Waste-Soil Weathering Reactions and Their Impacts on Trace Contaminant Migration and Sequestration

Chorover, Jon ; Mueller, Karl T. ; O' ; Day, Peggy ; Serne, R. Jeff

University of Arizona, Tucson

关键词: Illite;    Vermiculite;    Sediments;    Liquid Wastes;    36 Materials Science;   

DOI  :  10.2172/838400
RP-ID  :  EMSP-86984--2003b
RP-ID  :  FG07-02ER63504
RP-ID  :  838400

美国|英语

来源: UNT Digital Library

【 摘 要 】

High pH waste solutions are in gross chemical disequilibrium with the subsurface environment and react with sediment minerals, promoting dissolution and precipitation processes that impact 137Cs, 90Sr, and 129I speciation and migration behavior in the vadose zone. We have conducted long-term kinetic studies, with reaction times ranging from 1 to 369 d, to examine relationships between aluminosilicate weathering in the presence of synthetic tank waste leachate (STWL) and contaminant uptake and release. Our experiments employ a sequence of specimen clay minerals including illite, vermiculite, montmorillonite and kaolinite, which are also important reactive solids in the Hanford sediments. These studies have shown direct coupling between mineral transformation reactions and contaminant sequestration/stabilization.