The Norilsk diesel oil spill was an industrial disaster near Norilsk, Krasnoyarsk Krai, Russia. It began on 29 May 2020 when a fuel storage tank at Norilsk-Taimyr Energy's Thermal Power Plant No. 3 failed, flooding local rivers with up to 17,500 tonnes of diesel oil. President Vladimir Putin declared a state of emergency in early June. The incident has been described as the second-largest oil spill in modern Russian history, after the 1994 Komi pipeline spill, where 400,000 tonnes of crude oil were released to the environment between August 1994 and January 1995.