Iodine speciation and diffusion in a sand-groundwater system
The behaviour of iodide and iodate was studied in the Drigg sand-groundwater system. Diffusion coefficients were determined using both steady-state and infinite-couple geometry, and distribution ratios were determined over a wide range of concentrations and solid/solution ratios. The behaviour of both iodide and iodate appeared to depend on iodide/iodate concentration and microbial activity. At trace concentrations (1.0 E-11 M iodide or iodate), diffusion was very slow and there was a strong dependence of the distribution ratio on the solid/solution ratio. At high concentrations (1.0 E-3 M iodide or iodate), neither was sorbed and they appeared to diffuse without retardation. This is presumably because, in the presence of a large excess of iodine, the effect of microbial action is undetectable or microbes are inhibited. Fixation by microbial action is slow and for this reason 131I has been found to behave as a conservative tracer in field and column experiments.
Bibliographic Reference: EUR 13277 EN (1991) 33 pp., FS, ECU 5
ISBN: ISBN 92-826-2419-6
Record Number: 199110501 / Last updated on: 1994-12-02
Original language: en
Available languages: en