Improved acidity estimation by integrating comprehensive dissolved metal(oid)s data: A geochemical modeling case study of highly mineralized mine waters

• Author(s): Barroso, Ana Raquel ; Cravotta III, Charles A. ; Gomes, Patrícia ; Antunes, Isabel Margarida Horta Ribeiro ; Marinho Reis, A. Paula ; Valente, Teresa Maria Fernandes
• Date: 2025
• Persistent ID: https://hdl.handle.net/1822/97401
• Origin: RepositóriUM - Universidade do Minho
• Subject(s): Mine waters; acidity; PHREEQC; metal(oid)s concentration; modeling
• Document Type: Conference paper
• Language: English
• Contributor(s): Universidade do Minho

Description

This study introduces a geochemical modeling approach using PHREEQC to improve the accuracy of acidity estimates in waters influenced by acid mine drainage (AMD). AMD, common in regions like the Iberian Pyrite Belt, is characterized by low pH and high concentrations of metals, sulfate and acidity. Conventional methods, such as net acidity, often underestimate actual acidity by excluding additional metal(oid) s and bisulfate, particularly in highly mineralized waters. By incorporating factors like Fe, Al, Mn, other metal(oid)s, and bisulfate, these methods improve acidity estimation accuracy. Results demonstrate that these methods provide more precise acidity measurements, enhancing AMD monitoring and treatment strategies.