The results of geotechnical and geochemical tests on four on-site soils considered for construction of a liner for a proposed uranium tailings impoundment are presented. The interaction of five heavy metals (arsenic, chromium, zinc, molybdenum, and manganese) with four clay soils was investigated by batch tests on pulverized specimens and column tests on compacted specimens. A prototype mill tailing solution was used for the column leaching tests.

Atterberg limits, metal concentrations, and X-ray diffraction analyses established two soil groups of similar composition. The batch and column tests established two soil groups having similar adsorption characteristics, but they included soils having different compositions. The results of batch and column tests were in general agreement, though a few significant differences in adsorption characteristics were noted. The testing established a tentative ranking of the relative sorptive capacities of the four soils for the five metals, though further testing is recommended.