Biodiversity conservation threatened by global mining wastes

Mine tailings—the residue remaining after mineral processing—represent a serious risk to the natural environment, and the failure of tailing storage facilities has caused some of the most serious environmental disasters in history. However, the potential biodiversity impacts globally due to tailings are mostly unknown. Here we assess the spatial coincidence between 1,721 disclosed tailings storage facilities and currently protected areas (PAs) and other conservation priorities (Key Biodiversity Areas and remaining intact ecosystems). Nine percent of storage facilities are located within PAs, half of which were established after the PA was designated. Another 20% of storage facilities are within 5 km of a PA, indicating even larger risks posed by upstream facility failures. Despite international commitments to mitigating biodiversity loss, tailings storage facilities continue to be established within PAs, with an upward trend in the proportion established within already-existing PAs. Given our findings, it is unsurprising that biodiversity factors are rarely included when assessing and categorizing the risks posed by new and existing tailings storage facilities. Greater transparency and a holistic consequence-based approach, supported by data, monitoring and new technologies are needed to drive reform at local, national and regional levels.