In 1998, the Aznalcóllar mine-tailing spill caused one of the most environment disaster of Europe, 6 hm3
of both sludge and acid waters were spilled producing a strong pollution of the adjacent Guadiamar river
and the outskirts of the Doñana National Park. In this study, we analyze the impact of this spill in the river
water quality, from monthly data obtained between 1980 to 2003 in a sampling point of the Guadiamar
river. The higher contaminant levels, with pH values close to 3, occur at the beginning of the 1980’s. In the
latest years the concentrations of contaminant elements (Cd, Cu, Fe, Mn, Zn, etc.) show a descending
trend, mainly from 2002. The present-day levels of contamination are lower than those existing before the
spill, probably due to the mining activity cessation and the remediation measures carried out in the area