Conservation paradox: Large-scale mining waste in protected areas in two global hotspots, southeastern Brazil

Abstract

Irreversible losses of natural areas and damage to ecosystem services are caused by large-scale mining. These effects are prominent in Minas Gerais, which is home to a mining industry with hundreds of tailings dams concentrated in global hotspots: the Cerrado and the Atlantic Forest. We present an overview of the spatial overlap between protected areas (PAs), priority conservation areas (PCAs), tailings dams, and their influence areas. A total of 218 dams accumulated environmental costs and liability that are represented by 2.24 thousand million m 3 of tailings and industrial waste. Most dams (& 70%) are located in PCAs, 45 dams in conservation units, 58 in their respective buffer zones, and 51 in special protection areas. We have identified an urgent need to implement adequate public policies to establish management and monitoring mechanisms in PAs and PCAs and to address a scenario of high potential for socioenvironmental damage associated with tailings dams.

Mining Waste Challenges: Environmental Risks of Gigatons of Mud, Dust and Sediment in Megadiverse Regions in Brazil

“…Rather, the events that frequently cause pollution and silting in freshwater ecosystems occur within the properties of mining companies, and few are adequately reported to control and surveillance agencies [27]. Due to the high potential for environmental damage from waste dams, in the last decade, Brazilian public policies were implemented focusing on the creation of a national register and definition of monitoring and risk management requirements for these structures [6,39]. The national register helps improve governance because it contains a complete database.…”

“…Studies indicate that mining activities generate impacts and represent considerable risk, specifically for sites with high concentrations of endemic species of vascular plants, cave invertebrates, anurans, and birds [48][49][50]. Examples of this situation occur with dams and dump piles (Figure 2C) located in a matrix of Atlantic Forest fragments in the Quadrilátero Ferrífero region, a mosaic of 29 protected areas, and in two UNESCO Biosphere Reserves, "Serra do Espinhaço" and "Atlantic Forest" [6].…”

“…Despite catalyzing some general advances, the major obstacles to the implementation of the PNRS include the lack of financial resources and the difficulty of coordinating different government agencies [53]. In addition to the challenge per se of obtaining the financial and technological resources required for the management of gigatons of mining waste over decades or centuries, the high socio-environmental risk (and its corresponding long-term costs) of spatial association between megadiversity areas and mining sites should also be considered [6,54]. This scenario is also worrisome due to the gaps in knowledge on the volume of material deposited in dump piles and on the biogeochemical behavior of many toxic elements present in mining wastes [11,55].…”

“…The generation of mining waste is estimated to be 50 times higher in terms of annual volume [3], representing immense environmental risks and liability. However, despite the volume and the possibility of mining wastes containing hazardous substances, the discussion around proper and sustainable management of mining wastes has received relatively little attention from the general public, the scientific community, and decision-makers [4][5][6].…”

“…One factor that further complicates mining waste management is the location of mineral reserves in regions where the world's biological diversity is concentrated [6,14,15]. In this circumstance, Brazil is probably the nation with one of the greatest challenges as it ranks first among the 18 megadiverse countries and, at the same time, is one of the largest global producers of iron, bauxite, niobium, graphite, vanadium, tin, and manganese [16,17].…”