Abandoned locations after mineral exploration - environmental burden or perspective sources of raw materials?

Mining wastes represent a specific type of waste and, like sites after mining, represent sites where a comprehensive assessment of pollution at these sites needs to be approached, taking into account various specific conditions. Subsequently, the design of the remediation technologies used at a specific location must also be adapted to this fact. Until now, mining waste facilities (heaps and sludge ponds) have been treated as environmental burdens. However, it should be borne in mind that abandoned extractive waste facilities may be a significant source of minerals in the future, due to improved treatment technologies and combined with new requirements in the raw materials market (requirements for new useful components that have not been mined in the past). Many extractive waste facilities also contain elements that are currently listed as critical raw materials for the European Union. Within the project APVV-17-0317 "Antimony - a critical element and a dangerous contaminant affecting biodiversity in mining sites" a preliminary survey and research was carried out at selected sites in order to determine the potential of deposited materials as secondary sources of minerals. Samples of flotation sludge used in our research were taken at the localities of Dubrava, Medzibrod and Cucma from tailing ponds after the extraction of antimony, which is one of the critical raw materials for the EU.