Study of the generation of acid drainage in tailings piles from uranium mining

• Grant number: 18/14565-3
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2019
• End date: January 31, 2021
• Field of knowledge: Engineering - Sanitary Engineering - Environmental Sanitation
• Principal Investigator: César Augusto Moreira
• Grantee: César Augusto Moreira
• Host Institution: Instituto de Geociências e Ciências Exatas (IGCE). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Associated researchers: Amália Eugênia Matavelli Rosa ; Heber Luiz Caponi Alberti ; Pedro Lemos Camarero

Abstract

Mining to extraction and processing of raw materials mineral, which has extraction area (open pit or underground), beneficiation area and concentration of iron ore, release of tailings and tailings dams. The mining of ores of hydrothermal origin often results in a large accumulation of sulfide minerals in tailings piles, stable inside unexplored mineral deposits, more susceptible to changes under atmospheric conditions. The hydration and oxidation of mineral sulfides under surface conditions causes oxidation, release of cations and large amounts of sulfur in surface and groundwater, an aqueous product called acid mine drainage, characterization by the acidic pH and high amount of metals and, possibly, radioactive elements. The technical procedures most used in geochemical monitoring in areas in tailings piles are monitoring wells, which allow periodic measurements of the water table and chemical analyzes of the groundwater. Although they are indispensable tools, they result in occasional samplings with limited spatial representativeness. The diagnosis and environmental monitoring by application of Geophysics is attested by several scientific and technical studies, obtained in an indirect, non-invasive and extensive. The integrated use of direct (geochemical) and indirect (geophysical) methods may be an alternative in the study of the origin and flow of acid mine drainage in tailings piles with sulfides. Thus, this project aims to understand the generation of acid drainage tailings from uranium mining tailings with sulfides and the possibility of recognition of these areas in depth from surface mapping technique. Geochemical surveys of surface and groundwater are planned, accompanied by geophysical surveys using the DC resistivity, Induced Polarization and Gamaespectometry methods. The DC resistivity allows the recognition of percolation zones of groundwater acid drainage (enriched in dissolved ions). Induced Polarization is traditionally applied in the exploration of disseminated sulfide-type mineral deposits, and its use in this project aims at the recognition of sulfide zones within the tailings piles, adapting the method to environmental studies. The proposed use of Gamaespectometry is based on the hypothesis of surface radioactive emanations from the destruction of minerals in areas of acid drainage generation in depth. (AU)

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MOREIRA, CESAR AUGUSTO; INNOCENTI HELENE, LIVIA PORTES; HARTWIG, MARCOS EDUARDO; LOURENCO, REBECA; PACINE FEITOZA DO NASCIMENTO, MATHEUS MISTRINEL; TARGA, DEBORA ANDRADE. Geophysical and Structural Survey in the Diagnosis of Leaks at a Fuel Station in a Uranium Mine in Decommissioning Phase (Pocos de Caldas, Brazil). PURE AND APPLIED GEOPHYSICS, v. 178, n. 9, AUG 2021. (18/14565-3)

ALDANA ARCILA, ERIKA JULIANA; MOREIRA, CESAR AUGUSTO; CAMARERO, PEDRO LEMOS; STANFOCA CASAGRANDE, MATHEUS FELIPE. Identification of Flow Zones Inside and at the Base of a Uranium Mine Tailings Dam Using Geophysics. MINE WATER AND THE ENVIRONMENT, v. 40, n. 1, SI, p. 308-319, MAR 2021. (18/14565-3)

MOREIRA, CESAR AUGUSTO; NETTO, LEONIDES GUIRELI; CAMARERO, PEDRO LEMOS; BERTULUCI, FERNANDA BARBOSA; HARTWIG, MARCOS EDUARDO; DOMINGOS, REINALDO. Application of electrical resistivity tomography (ERT) in uranium mining earth dam. JOURNAL OF GEOPHYSICS AND ENGINEERING, v. 19, n. 6, p. 15-pg., 2022-11-28. (18/14565-3)

MOREIRA, CESAR AUGUSTO; CASAGRANDE, MATHEUS FELIPE STANFOCA; DE SIQUEIRA BUCHI, FERNANDA MIRANDA; TARGA, DEBORA ANDRADE. Hydrogelogical characterization of a waste rock pile and bedrock affected by acid mine drainage from geophysical survey. SN APPLIED SCIENCES, v. 2, n. 7, JUN 17 2020. (18/14565-3)