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Compacted clay layers are commonly used as liners to limit acid-mine drainage (AMD) percolation into the surrounding environment from containment areas or ponds. In the long term, this practical and sometimes economical means of AMD disposal has often presented other considerable environmental challenges. The chemical quality of soil, river water and groundwater surrounding evaporation ponds lined with clay was determined at Iron-Duke Mine in Glendale, Zimbabwe. At this mine over 150m³/d of wastewater containing AMD were discharged daily for over a decade. The soils located downslope in relation to the ponds and closer to the ponds were acidified (pH 2.8–4.4) and enriched with salts. The level of contamination was highest within 15m from the ponds and at 2–6m depths from the surface. The variability in soil pH and electrical conductivity with position, distance from the ponds and depth from …