the main industrial pollution source is norilsk nickel in monchegorsk—the large smelters responsible for over 80% of the sulfur dioxide emissions and for nearly all nickel and copper emissions. since 1998, so emissions in the area have dropped by almost 60%, from 88.3 thousand tonnes to 37.3 thousand tonnes in 2016, according to norilsk nickel. by 2023, norilsk nickel plans to reduce its overall emissions by 75% as part of its long-term development programme. other polluters of note include the thermal power stations in apatity and murmansk.