Impacts of Mining Contamination in the Pilcomayo River Basin and Opportunities for Remediation
Mining has shaped the Bolivian city of Potosí for nearly five centuries, generating significant economic activity alongside severe environmental and public health consequences. The Pilcomayo River Basin, which originates in the Potosí mining region and flows through Bolivia, Argentina, and Paraguay, is heavily contaminated with heavy metals originating from acid mine drainage, tailings, and inadequately treated wastewater. Communities and indigenous peoples living along the basin face serious risks from contaminated water and sediments, poor air quality from windblown particulates, and limited access to environmental health resources.
This project was conducted in partnership with Advanced Mineral Technology South Korea (AMTSK), a company planning to deploy water remediation technology in the Pilcomayo Basin. Using water and sediment quality data collected by the Trinational Commission for the Development of the Pilcomayo River Basin from 2016 to 2024, the team developed a composite hazard ranking system integrating water contamination, sediment contamination, social vulnerability, and population density to identify priority locations for remediation intervention. Seasonal contamination dynamics, sediment-water partitioning chemistry, and air quality modeling were also analyzed to inform targeted remediation strategies.
The analysis identifies the river stretch near Potosí, particularly around San Antonio and the Huaynamallu River, as the highest-priority location for AMTSK's pilot treatment system, with cadmium, lead, arsenic, zinc, and iron identified as the top contaminants of concern. The findings are presented through two publicly accessible, bilingual web applications designed to support ongoing decision-making by government agencies, researchers, and community stakeholders across the basin.
Acknowledgements
UC Santa Barbara Bren School: Dr. Arturo Keller, Distinguished Professor; Dr. Jayajit Chakraborty, Professor
UC Santa Barbara Geography Department: Dr. Hugo Loaiciga, Distinguished Professor
AMTSK: Jeff Thoreson, CEO; Muhammed Khan, Chairman of the Board of Directors
Universidad Autónoma Tomás Frías: Edgar Bohrt, Ingeniero
Comisión Trinacional para el Desarrollo de la Cuenca del Río Pilcomayo: Juan Diego Fontana, Ingeniero Civil
David Choquehuanca, Ex-Vicepresidente de Bolivia; Marco Antonio Copa Gutiérrez, Gobernador interino del departamento de Potosí en Bolivia; Diputada Nacional Cintya Lidia Ruíz Farfán de Tarija, Bolivia; Alvaro Ruiz Garcia, Viceministro de Medio Ambiente y Agua; Barrio Cantumarca de Potosí, Bolivia.
The Professional Environmental Management Association (PEMA)