Authors: Koitzsch, Y; Klemm, S; Muehl, A; Barnekow, U; Speer, M
Editors: Dight, PM
Conference: First Asia Pacific Slope Stability in Mining Conference, 6–8 September, Brisbane
Published: Australian Centre for Geomechanics, Proceedings of the First Asia Pacific Slope Stability in Mining Conference, pp.531-544, Perth
The remediation of the East German uranium mining sites operated and used until 1990 started in 1991 and was funded by the German Federal Government. However, most of the numerous abandoned uranium mining sites of third party property that were distributed all over Saxony were not included. In 2003 the Federal Government and the Free State of Saxony agreed to jointly fund the remediation of those abandoned mining sites of high priority. Wismut´s department for Project Management of Wismut´s Abandoned Saxonian Mining Sites was given the responsibility for the project management. The Dänkritz 2 uranium mill tailings pond is one of those abandoned sites (area: ca. 11 ha; vol. ca. 0.9 Mill. m³). Mill tailings were discharged during the 1950s surrounded by a max. 12 m high autostable ring dam, which was already reshaped during the 1960s to improve geotechnical stability. Dynamic stability calculations, applying the finite element program PLAXIS, were carried out by CDM Smith as part of the remediation design. They resulted in insufficient dynamic stability with respect to the maximum credible earthquake. In addition, soft fine-grained tailings needed to be stabilised to place a multi-layer type surface cover. Wismut designed the tailings remediation project. The paper will particularly focus on the advanced constitutive models used for the slope stability analyses of the embankment under dynamic loads and of the stability of the fine-grained tailings during interim cover placement.
Keywords: stabilisation of tailings management areas, tailing pond remedation, uranium mill tailings, dynamic numerical analyses
Koitzsch, Y, Klemm, S, Muehl, A, Barnekow, U & Speer, M 2016, 'Remediation of the uranium mill tailings pond Dänkritz 2 — seismic slope stability analysis and serviceability limit state design', in PM Dight (ed.), Proceedings of the First Asia Pacific Slope Stability in Mining Conference
, Australian Centre for Geomechanics, Perth, pp. 531-544.
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