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The article presents the results of the study of sulfur-containing gases (carbon disulfide, CS2, and dimethyl sulfide, C2H6S) in the air above the sulfide tailings and in the soils in Komsomolsk settlement. Concentrations of CS2 (gas of the second hazard class) and C2H6S (gas of the fourth hazard class) in the air above the tailings exceeded the average maximum permissible on-time concentration (MPCot) by 20 times and 9 times, accordingly. Because of the alarming medical statistics on childhood morbidity, vegetable gardens in houses in the settlement were selected for measuring gas concentrations and metal contents. Concentrations of CS2 varied from 2.2 to 27 µg/m3 and exceeded MPCdn at 24 locations out of the 31 selected points. Concentrations of C2H6S varied from 120 to 440 μg/m3 and exceeded MPCot at 9 out of the 31 points. Particularly high gas concentrations were detected at a school and kindergarten. Geochemical study showed high concentrations of arsenic, zinc, and lead in garden soils compared to their background values. Mathematical models of the distribution of hazard indices indicated that about 633 residents of Komsomolsk are at risk of diseases related to respiratory organs and liver damage, and approximately 215 inhabitants of Komsomolsk are exposed to the combined effects of CS2 and C2H6S and are at a risk of neurotoxic disorders. [ABSTRACT FROM AUTHOR]

The article presents the results of the study of the vapor streams from sulfide-containing tailings after gold mining by cyanidation (Ursk waste heaps, Kemerovo region, Russia). The gas survey of sulfur dioxide, dimethyl sulfide, dimethyl sulfoxide, carbon disulfide, and N-containing substances concentrations was carried out using a portable device GANK-4 on a series of profiles covering the waste heaps and the surrounding area with simultaneous measurement of temperatures in the air and soil. The concentration maps-schemes of the studied gases in the surface layer were constructed. The high positive correlation of gases between themselves is established, which indicates similar mechanisms of their formation. The electrical resistivity tomography determined the internal structure of the waste heap. Active "breathing" zones were identified in which the maximum fluctuations in the concentrations of sulfur, selenium, and nitrogen-containing compounds in the near-surface air layer were recorded. Such zones are marked with lower resistances in comparison with other areas on the geo-electric profiles. There is an inverse correlation between the resistivity of the tailings and its temperature and a direct correlation between the concentration of gas in the air and the temperature of the soil. High concentrations of CS2, the volatile gas compound of the second hazard class, were found in the concentrations that exceed 6–8 times the daily average norm. Further investigation of the mine tailings seasonal transformation with the production of toxic gases deserves special attention due to high environmental risks and poor knowledge of this problem. The oxidation of ore cyanidation wastes in summer and methylation in winter due to seasonal temperature fluctuation lead to production of gases of great concern including toxic СS2. [ABSTRACT FROM AUTHOR]