The mine has been welcomed in Westport, with Rangatira Developments promising 58 direct full-time jobs.
The open-cast would cover 144ha, including 12ha of the conservation estate and 100ha of the Westport water conservation reserve. The remainder is private land.
However, despite winning consent from the West Coast Regional Council and Buller District Council, the proposal has some significant hurdles to overcome.
The Department of Conservation has not yet ruled on the request for access, or the district council on access to water conservation land, which covers the source of the Westport town water supply.
Coal Action Network Aotearoa said today this would be the first test of whether there had been a real change in conservation policy with the new Government.
Forest and Bird has also called on Ms Sage, a former Forest and Bird staff member, to "please" represent the public and refuse the access.
Ms Sage has the ultimate decision making on that.
"Earlier this month, Conservation Minister Eugenie Sage signalled there would be no new mines on conservation land," Coal Action Network spokeswoman Rosemary Penwarden said.
"This is now her test: will she allow a coalminer to take the top off a mountain, in an area that contains the endangered great spotted kiwi?
"Or will she allow coalmining to go ahead, wiping out crucial biodiversity for coal that, ultimately, will end up in the atmosphere, causing climate change?"
She said the mining scar from Te Kuha would be visible from downtown Westport and the road through the Buller Gorge.
Forest and Bird said in a statement the mine could push great spotted kiwi and other endangered species such as South Island fernbird and the West Coast green gecko closer to extinction.
"Everybody agrees that this area has high ecological values," Forest and Bird chief executive Kevin Hague said.
"It's one of our forgotten places - home to the largest population of our rarest butterfly, but languishing in the lowest category of conservation land."
Forest and Bird said it may appeal the council consents with the Environment Court.
The West Coast Regional Council said last night it had granted consents after a joint application to it and the Buller District Council.
A hearing was held over nine days, with 744 submissions.
Regional council chief executive Mike Meehan said the process had been robust.
"The imposed conditions are robust and thorough and subject to input from all parties," Mr Meehan said.
The decision is subject to a 15-day appeal period.
The commissioners' decision found there would be severe to substantial adverse effects in the short term, reducing to moderate or slight over time.
"In balancing the matters required under the statutory instruments, we are conscious of the fact that, over the last four years, Buller has faced significant employment losses (in excess of approximately 1000 redundancies).
"While the mine would not fill the gap, we are satisfied that, in economic terms, the mine proposal at Te Kuha would help to potentially offset some of those losses.
"At the end of the day, the vegetation and habitats ... and landscape, would retain the necessary characteristics to ensure their significant status is protected."
The minister's decision to rule out new mining on conservation land surprised many leaders on the West Coast. It was announced as part of the incoming Government's Speech from the Throne in Parliament, and Ms Sage said yesterday that meant it had backing and would happen.
In Greymouth on Monday, Ms Sage met Mayor Tony Kokshoorn, West Coast Regional Council chairman Andrew Robb and Minerals West Coast.
She told the Greymouth Star she wanted to use the parliamentary address from the throne to signal the clear policy intention.
The ban did not affect existing mines on conservation land. She said the decision was made to flag the mining change early for the industry.
"We've got a climate crisis. We need to significantly reduce our emissions. New coalmines don't help to achieve that goal."
The long proposed Bathurst mine was "hugely controversial" and would cause major loss of biodiversity and landscape values on the Denniston Plateau, she said.
When it came to gold, which currently accounts for 175 jobs on conservation land on the West Coast, Ms Sage said she was "looking at how it (legislation) would affect alluvial gold".
"I can't say anything further. Listening."
- By Laura Mills
