神东煤矿区高氟矿井水季节成因分析及灌溉风险.

Mine water poses severe threats to the quality of the water supply and ecological environment of the Shendong mining areas owing to its excessive fluoride (F-) content. Previous studies have revealed the spatial distribution, sources, and geochemical controls that cause F- enrichment in Shendong mine water. However, seasonal distribution and quality assessment of elevated fluoride in the mine water are not fully understood. In total, 35 water samples were collected from the Shendong coal-mining area during the dry and wet seasons, and the seasonal distribution and geochemical sources were characterized and discussed. In addition, the quality assessment posed by mine water fluoride to environment was assessed.The results showed that the F- contents of mine water samples ranged from 0.16 to 13.96mg/L (mean 4.43mg/L) and from 0.16 to 17.60mg/L (mean 4.89mg/L) during the dry and wet seasons, respectively. The F- content of mine water in dry season is obviously higher than that in wet season. F- was significantly negatively correlated with Ca2+ and positively correlated with HCO3- and Na+ in mine water. Important factors identified as having an effect on F- in mine water included the dissolution of F-bearing minerals, cation exchange and competitive adsorption. In addition, the quality assessment of high groundwater fluoride to environment showed that 100% and 66.67% of low F-mine water are suitable for ecological irrigation, while 92.00% and 96.15% of high F-mine water are not suitable for ecological irrigation during the dry and wet seasons, respectively. [ABSTRACT FROM AUTHOR]