Underlying Causes of Long-Term Environmental Pollution by Waste from an Abandoned Metal Mining District: When Legislative and Remediation Measures Are Ineffective

Since ancient times, mining activities have been recognised as having a strong environmental impact. Due to the extraordinary amount of waste and impacts on the landscape, environmental concerns caused by mining can be found worldwide. The risks associated with mining waste are of great concern, especially when these residues come from metal mining and its associated potentially toxic elements that can be released into the environment. The reality of many of these metal mining areas is that, despite the extensive regulatory frameworks and remediation techniques applied, they continue to have high levels of contamination, posing a source of environmental and public health risk to their surroundings. The issues underlying this situation are details that can only be detected by experience in the management and thorough knowledge of the dynamics of these tailings in the long term. And in many cases, the key is in the details. For this purpose, the case of the former metal mining district of Cartagena-La Unión (SE Spain), one of the most affected areas in the European continent by these metal mining wastes, has been analyzed. In conclusion, it has been shown that the legal status of these waste and mining operations and the lack of control and effectiveness of rehabilitation activities are behind the worrying environmental situation of these areas. The interaction between the legal framework and the environmental and technical knowledge of these tailings and mining areas reveals practical issues beyond the scope of general analysis. This case study, conducted in the main Spanish metal mining area, concerns waste volume, and its findings offer the potential to improve the safety and environmental quality of metal mining regions elsewhere.