The study of the chemical composition of the snow cover for the environmental assessment of atmospheric air is widely used for different pollutants and has shown its high indicator efficiency. Snow cover during the winter period (5–6 months) accumulates atmospheric pollution and saves geochemical information until the beginning of the snowmelt period. Atmospheric air pollution in the potash industry is formed due to emissions from ore-processing plants, ventilation shafts, and the dusting of salt dumps. Emissions of the potash industry contain KCl, NaCl, and suspended solids that form soil salinization at one of the world's largest potassium salt deposits, the Verkhnekamskoye potash deposit. However, the high solubility of salts makes it difficult to assess the distribution of the main pollutants near technogenic sources. To assess the transformation of the chemical composition of snow in areas affected by the potash industry, the indices Cl/Na+, Cl/SO42−, and Na/K are proposed. It has been established that high Cl– content relative to Na+ proves that NaCl is not the only source of Cl– in the atmosphere. The Na/K index, the lowest value found in the industrial area, confirms the prevalence of K+ over Na+ in industrial emissions. Most likely, the main part of Cl– content near the potash plants is associated with KCl emissions. The exclusively technogenic character of high Cl– concentrations in atmospheric air is evidenced by the Cl–/SO42– ratio in the snow cover. Near the potash plant, this ratio is twice as high as in the Arctic snow and ten times higher compared to other functional areas of Berezniki. These indices can be used for environmental monitoring in areas affected by the potash industry or other enterprises with high content of water-soluble salts in emissions.