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2 Publications
Investigation of the Migration Behavior of Uranium in an Aquifer System Rich in Humic Substances: Laboratory Column Experiments
Pompe, S.; Artinger, R.; Schmeide, K.; Heise, K.-H.; Kim, J. I.; Bernhard, G.;
The migration behavior of uranium in a sandy aquifer system rich in humic substances was studied in laboratory column experiments. For the investigations we used a Pleistocene aeolian quartz sand and groundwater GoHy-532 from the Gorleben site (Germany). The column experiments were performed in a glove box under anaerobic conditions (Ar + 1 % CO2). 232U(VI) was used as a tracer. The migration behavior of uranium was investigated as a function of the uranium/groundwater equilibration time before injection into the column, the groundwater flow velocity and the column length.
From the breakthrough curves one can conclude that a part of the injected uranium migrates slightly faster than groundwater. The observed migration behavior is attributed to the association of a part of uranium with humic colloids, which move faster due to size exclusion processes. Depending on the experimental conditions the recovery of humic colloid-bound transported uranium amounts to 0.4 up to 7.6 %. The recovery of non-retarded colloid-borne uranium increases with increasing uranium/groundwater equilibration time before injection into the column. Beyond it, the recovery of humic colloid-borne uranium decreases with decreasing groundwater flow velocity and increasing column length, which corresponds to an increasing residence time in the column.
The results refer to the fact that the migration behavior of uranium is strongly influenced by kinetically controlled interaction processes of uranium with humic colloids.
  • Contribution to external collection
    FZKA 6324, Wissenschaftliche Berichte Forschungszentrum Karlsruhe, (G. Buckau, ed.). Karlsruhe 1999, p. 219.
  • Lecture (Conference)
    Fourth Project Meeting of the EU project: Effects of Humic Substances on the Migration of Radionuclides: Complexation and Actinides, Leuven, Belgium, 19.-20.11.1998

Publ.-Id: 2140 - Permalink