Contrasting Spectroscopic Characterization and Environmental Behavior of Dissolved Organic Matter in Shallow and Deep Mine Water of Shendong Mining Area, China

Underground reservoirs have been widely used to facilitate mine water storage in the Shendong mining area. Unfortunately, problems with suspended matter and soluble pollutants in underground reservoir water have occurred. However, as indicators of the mine water environment, the spectroscopic characteristics, geochemical sources of dissolved organic matter (DOM), and influence on the hydrochemistry of mine water remain unclear. In this study, DOM concentration was revealed in the mine water of Shendong mining area, ranging from 0.12 mg/ L to 4.90 mg/L, with a mean value of 0.93 mg/L. EEM-PARAFAC models and spectral parameter analysis identified autochthonous components and terrestrial substances that dominated shallow and deep mine water DOM, respectively. Compared with shallow mine water, DOM had lower degrees of humification and more freshly terrestrial substances with higher biological index (BIX), and humification index ( HIX), lower E2/E3 ratio, and a254 values in deep mine water owing to emulsion oil leakage. The DOM spectral parameters were helpful in conveniently monitoring the change in mine water quality (total dissolved solids (TDS) and total nitrogen (TN)) by significant correlation.