Although the amount of pollutants emitted to the air have been falling since the 1980s, the air is still polluted with sulphur dioxide from the mining industry that the Soviet Union rapidly developed in the early 1950s.
Meskipun sejumlah kadar pencemar yang terlepas ke udara semakin berkurang pada dasawarsa 1980-an, udara masih dicemari oleh sulfur dioksida dari industri pertambangan yang secara cepat dibangun oleh Uni Soviet pada permulaan dasawarsa 1950-an.