The NSW Planning Commission has given the green light to a new multi-billion dollar coal mine for the state.

Placed immediately next to some of Australia’s most productive farm land, the Watermark open-cut mine will be built on the Liverpool Plains in northern NSW.

The Watermark mine is an initiative of Chinese coal giant Shenhua Group, and will dig up about 10 million tonnes of coal a year for 30 years.

The huge project was given the go-ahead after the Planning Commission found that farming would still be possible on the fertile blacksoil plains next to the mine.

The commission says groundwater impacts should be minimal, and farmers will be able to access compensatory water from the mine operator if their supplies are harmed.

Farmers are understandably opposed to the mine plan due to its potential impact on water availability and the land itself.

Anti-resource activists from the Lock the Gate Alliance say the approval has destroyed the credibility of NSW mining laws