Influencia de las explotaciones auríferas de la zona baja de la cuenca del río Dagua sobre la contaminación por mercurio en la bahía de Buenaventura (Valle del Cauca, Colombia) de 2004 al 2017

Abstract

This work was developed during an internship in the Colombian Ocean Commission in the Committee for the Prevention of Marine Pollution - Mining and Water Resource Group. The project study area is lower Dagua River basin region, connected to the Buenaventura bay in the Pacific Ocean. In this region environmental, political, and violence conflicts are common and are related to legal and illegal gold exploitation, resulting in high levels of mercury pollution. Despite this historical fact, control by the authorities has been ineffective, and the region is considered as a “red zone” due to its high level of conflicts and governability difficulties. Mercury has affected the river bed and the Buenaventura bay. This pollutant has been found in commercial fisheries on species such as mojarra, mullet and croaker; in pelicans; in crustaceans such as crabs, tiger shrimp and prawns; and in benthic communities. This project is aimed to identify and analyze the trend of the presence of mercury in the Buenaventura bay and the lower area of the Dagua river basin from 2004 to 2017 through secondary information from government entities, academic institutions and independent researches. Control and mitigation measures of the negative impacts of gold mining will be identified. The magnitude of the gold mining activity impact will be determined in order to call for a national alert