Dynamics of changes in the composition of quarry waters as exemplified by the gypsum deposit at the Arkhangelsk region

The article presents the results of a two-year study of the composition of quarry waters at a gypsum deposit located in the Kholmogory District of the Arkhangelsk Region. Systematic monitoring included determining the physicochemical parameters in key process zones: the quarry water collector (sump) and the settling pond of the treatment facilities. To obtain the analytical base, standard methods were used: GOST 31957-2012, PNDF 14.1:2:4.157-99, and others. It was found that the dry residue indicator of water varies in the range of 1190—6700 mg/dm³ with pronounced seasonal dynamics: maximum in spring (March) and minimum in summer (June). The dominant component is sulfate ion (up to 3700 mg/dm³), which is typical for gypsum deposits. Exceedances of the maximum permissible concentrations for river waters used for fishery and/or drinking purposes were revealed for the content of sulfates and strontium, and occasionally for magnesium, iron, zinc, copper, cadmium and aluminum. Efficiency of treatment facilities was demonstrated, ensuring a reduction in pollutant concentrations to 29 %. The results are consistent with the data of other researchers, but demonstrate the specificity of the territory under consideration – increased content of sulfates and strontium and slow sedimentation of suspended matter. The obtained data are of interest to mining enterprises, environmental organizations and scientific institutions dealing with the problems of ecology of mining production.