Une après-midi passée sur l'ancien site minier du Rio Tinto a permis de comprendre l'ampleur de l'impact environnemental d'un ancien site minier.

L'eau du Rio Tinto a un pH compris entre 1 et 2, ainsi que des concentrations élevées en métaux lourds.

The Rio Tinto system in the province of Huelva, south-
western Spain, has great historical significance as well as
environmental interest. It is one of the most polluted flu-
vial-estuarine systems in the world and most likely has
been so for thousands of years. It is in the headwaters of
this river that mining supporting the Copper Age and
Bronze Age took place. The estuary, at the town of Palos
de la Frontera, was the origin of Columbus’ expedition in
1492 and for subsequent trips. Most recently, the city of
Huelva has become the site of one of the most polluted
industrial areas of the world. It is possible, however, that
the pollution of the system began thousands of years ago
with the original mining of the massive sulfide deposits
near the headwaters of the Rio Tinto.