The methane emissions from abandoned fossil fuel infrastructure globally are larger than any single country except for China, the USA, and Russia. But cleaning up these abandoned facilities would cost ~$100 billion according to the International Energy Agency.
www.theguardian.com/environment/...
Abandoned infrastructure one of the biggest polluters in the world – report
Emissions from abandoned coalmines, oil and gas wells globally are larger than any single country except China, the US and Russia
