ANALYSIS OF THE IMPACT OF LOCAL CORRECTIVE MEASURES ON THE INPUT OF CONTAMINANTS FROM THE ODIEL RIVER TO THE RIA OF HUELVA (SPAIN)

摘要

The contamination of the Tinto and Odiel Rivers represents one of the most serious acid mine drainage (AMD) problems worldwide. AMD causes two problems: the contamination of the hydrological network and the contamination of the Ria of Huelva, an estuary formed by the union of these two rivers. The river Odiel carries to the estuary a large amount of chemical pollution of mining origin with extreme pH values, sulfates and heavy metals characterized by monthly samples throughout a 9 year period. In this river, corrective measures have been carried out in 21 small abandoned mines. In this article, a methodology is developed that allows us to see that these measures, which have resulted in remarkable local improvement, have not had a significant effect on the contamination introduced by this river into the Ria of Huelva.