BitRiver’s Russian subsidiary had net zero carbon emissions in the second half of last year, the first firm in Russia to receive that accreditation, the company said in a Wednesday press release shared with CoinDesk.

The report was verified by U.K.-based standards testing firm BSI.

“A positive opinion on zero greenhouse gas emissions from an international auditor may be considered, without exaggeration, a watershed event for the industry,” BitRiver Rus CEO Igor Runets said in the press release.

The environmental impact of crypto mining has been at the center of regulatory debates in the U.S. and Europe, with some estimates putting the Bitcoin network’s energy consumption on a par with countries like Argentina.

The testing firm verified that BitRiver’s direct and indirect emissions of carbon dioxide (CO2) were equal to zero, in accordance with the standard ISO 14064-1:2006. Greenhouse-gas emissions are calculated using international renewable energy certificates (I-RECs) that certify the renewable origin of electricity.

BSI did not respond to CoinDesk’s request to confirm the report at the time of publication.

Verifying BitRiver’s greenhouse gas emissions report was an “unusual project,” David Fardel, BSI’s CEO for CIS and France, said in the statement.

BitRiver Rus, based in Irkutsk, Siberia, is one of the largest mining firms in Russia, offering hosting services for large-scale mining. Its data centers are 300 megawatts, and the company plans to increase their size over sixfold by the end of 2022. The company manages five proprietary data centers it has built from scratch, and is implementing a further 15 projects in Russia and abroad, according to the statement.

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