Characterisation of the environmental impact of the Rodalquilar Mine, Spain by ground-based reflectance spectroscopy

Abstract

This study has investigated the utility of using field-based reflectance spectroscopy to characterise the distribution and nature of the dispersion of tailings material from the Rodalquilar mine, Spain. Field spectral measurements covering the visible to shortwave infrared wavelengths (0.35 to 2.5 m) and laboratory analyses were performed on samples collected along the length of the main river within the Rodalquilar valley. The nature and degree of contamination at locations within the river channel were calculated by a range of spectrometric analyses. The resulting mineral maps identified that tailings material with significant amounts of hematite with minor jarosite, ferrihydrite and goethite, and clays, primarily alunite and kaolinite, with minor smectite and illite, had been dispersed along the length of the river. These results have been used to improve understanding of the erosion and remediation history of the Rodalquilar mine. This study has shown the potential of field-based reflectance spectroscopy, integrated with ground positioning and digital mapping systems, as a real-time mapping methodology enabling immediate, accurate characterisation of the nature and scale of tailings material dispersion.