Some of horse racing's biggest names have spoken out in support of Hunter Valley breeders facing renewed plans for a coalmine on their doorstep.

Miner Anglo American plans to resubmit its Drayton South mine in coming months after the Planning and Assessment Commission (PAC) rejected its initial proposal in October last year.

The company's new plan includes a 25 per cent smaller footprint for the mine, which would also be moved behind a ridge line so it could not be seen or heard.

But Gai Waterhouse, Bart Cummings, Gerry Harvey and TV presenter Francesca Cumani are standing behind breeders, calling for the plan to be abandoned and a 10km buffer between mining developments and the region's equine cluster to be legislated.

Ms Waterhouse told AAP she'd be sad to see breeders, including the internationally renowned Darley and Coolmore studs, move from the region.

"I buy from those farms so I am part of the industry even if I'm not directly on their doorstep," she said.

"I feel passionately for them."

It's thought the region is responsible for half of all thoroughbreds born in Australia.

Anglo American says the project will protect 500 of its workers when its current Drayton mine runs out of coal in 2017.

It hopes a completed Environmental Impact Statement will be released before July.

In rejecting the original plan the PAC found Anglo American's 100 million-tonne project was a threat to the Hunter's thoroughbred and tourism industries.

It said its economic benefits did not outweigh risking Darley and Coolmore.