A Russian mining giant behind an enormous Arctic fuel spill last month said Sunday it had suspended workers at a metals plant who were responsible for pumping wastewater into nearby tundra.

Norilsk Nickel cited a "flagrant violation of operating rules" in a statement announcing it had suspended employees responsible for dumping wastewater from a dangerously full reservoir into wildlife.

The incident occurred at the Talnakh enrichment plant near the Arctic city of Norilsk, the company said, one month after the unprecedented fuel leak sparked a state of emergency declared by President Vladimir Putin.

More than 21,000 tonnes of diesel leaked from a fuel storage tank at one of the company's subsidiary plants near Norilsk. The fuel seeped into the soil and dyed nearby waterways bright red.

Employees of Russia's state-owned oil pipeline monopoly Transneft take part in the clean-up operation after the massive fuel spill in the Ambarnaya River last month
Employees of Russia's state-owned oil pipeline monopoly Transneft take part in the clean-up operation after the massive fuel spill in the Ambarnaya River last month AFP / Irina YARINSKAYA

A source told Interfax news agency Sunday that in the most recent case, around 6,000 cubic meters of liquid used to process minerals at the facility had been dumped and that the discharge had lasted "several hours".

It was impossible to determine how far the wastewater had dispersed, the source said.

Independent newspaper Novaya Gazeta published videos from the scene showing large metal pipes carrying wastewater from the reservoir and dumping foaming liquid into nearby trees.

The journalists claimed the factory deliberately funnelled the wastewater into wildlife areas and hastily removed their pipes when investigators and emergency services arrived on the scene.

Map locating Russian mining giant Norilsk Nickel's Talnakh enrichment plant near the Arctic city of Norilsk
Map locating Russian mining giant Norilsk Nickel's Talnakh enrichment plant near the Arctic city of Norilsk AFP / Fabien MARCHESINI DUFAU

The Investigative Committee, which probes serious crimes, said it had received reports of "unauthorised dumping of liquid waste into the tundra" on the site of the facility, and had opened an enquiry.

Heavy machinery used to clear the pipes crushed a car delivering officials to the scene, Novaya Gazeta reported.

Interfax said no one was injured in the incident which was also being probed.

Norilsk Nickel spokeswoman Tatiana Egorova earlier Sunday told AFP that employees of the factory had pumped out "purified water" and that an internal investigation was under way.

Russia's natural resources agency said the decision to remove water from the reservoir was taken to avoid an emergency after heavy rains and recent tests had caused water levels to increase dramatically.

The local emergency services in a statement said the wastewater was not likely to reach the nearby Kharayelakh river.

The massive fuel spill last month took place at a plant owned by a subsidiary of Norilsk Nickel, which had said that the fuel tank had collapsed or sank due to melting permafrost due to climate change.

Putin declared an emergency situation after the accident and the head of Norilsk Nickel, oligarch Vladimir Potanin, promised to pay the costs of the clean-up.

The Russian authorities said earlier this month they had cleared the spill from the surface of a river, but the full clean-up could take years.

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