"I think every single bit of koala habitat is critically important," said Mr Kean, as he stood before an enclosure containing a rescued animal snoozing in a tree. "I want to make sure that our kids and their kids and their kids will be able to see koalas in the wild, and that means protecting their habitat."

About 40 kilometres away from where the minister stood at One Mile is 52 hectares of prime koala habitat at Brandy Hill, which has become a high-profile battleground over this very issue. Construction materials company Hanson wants to clear the land as part of a proposal to expand its quarry.

The state's Independent Planning Commission approved the quarry expansion in July.

The community opposition to the expansion has been growing and spreading, with famous names, including singers Olivia Newton-John and Jimmy Barnes, speaking out against the proposal in recent days.

The fate of the project now rests with the Federal Environment Minister Sussan Ley. The minister is considering the quarry expansion, and its impact, under the Environment Protection and Biodiversity Conservation Act, and she is due to give a decision on October 13.

At the sanctuary's official opening, Matt Kean said "the loss and fragmentation of koala habitat is the number one threatening process for koalas, and we're seeing that right here in Port Stephens".

"I think we should be doing everything we can to protect koala populations and their habitat, and that means securing that habitat into the future," he said.

"So my message to the Federal Environment Minister is, 'You should be looking very closely at this Brandy Hill decision, because a lot is turning on the decision you will make'."

The minister said the state's decision went through a "rigorous assessment process", but "things have changed since the bushfires".

"I think the Federal Environment Minister should be taking that into account when she makes her decision this October," her NSW counterpart said.

A recent state parliamentary committee report into koala populations and habitats estimated at least 5000 animals had died in last summer's bushfires. The report, released in June, said loss of habitat posed the most serious threat to koala populations, and it held a stark warning. Without urgent government intervention, the koala would be extinct in NSW by 2050.

When it was mentioned to Mr Kean that the state's approval of the Brandy Hill project was given after the bushfires, he responded, "These are matters for the Planning Minister, but certainly as far as I'm concerned, as the Environment Minister, we should be doing everything we can to protect koala habitat, and that includes Brandy Hill."

He later told the Newcastle Herald, "I think that the bushfires were an absolute game-changer, and decisions that were taken prior to the bushfires may not necessarily be the same ones that should have been taken after the bushfires. That's a matter for the planning process."

Kate Washington, the state Member for Port Stephens and the Shadow Environment Minister, was also at the sanctuary's official opening. She said Mr Kean's words didn't reflect the actions of the government he was a member of.

"The decision to approve and fast-track Brandy Hill was made after the bushfires," Ms Washington said. "That's it. So to push that responsibility onto Sussan Ley now, it's hypocrisy.

"Extinction is not an option, and the community will keep fighting to stop the Brandy Hill Quarry expansion, because they know what's important and we just hope, for goodness' sake, Sussan Ley will too."

Members of community groups who have been leading the fight against the quarry expansion may not have been at the official opening, but they heard about the minister's comments. Victoria Jack, campaign manager for Save Port Stephens Koalas, interpreted Mr Kean's words to mean, "He wants Sussan Ley to reject the Brandy Hill Quarry expansion".

"What Matt Kean's comments show is that he can see the tide has turned," said Dr Jack. "Australians will no longer tolerate the destruction of koala habitat because we want our governments to do what it takes to ensure koalas are here for future generations."

.At the official opening of the Port Stephens Koala Sanctuary, the focus was on the future, but there was also hindsight, looking at what it took to get here.

"It's a mixture of relief and great satisfaction, it's been five years in the making," said Port Stephens Koalas' chief executive officer Ron Land, one of the prime movers of bringing this facility to reality.

"Now we can get on and get back into doing what we do best, and that is to look after koalas and try and save as many of them as we can."

For years, volunteers worked in a demountable building, but now the sanctuary has a state-of-the-art hospital and rehabilitation enclosures. The facility is also developing a breeding program, to help ensure the species' future. On Friday, the official party met a couple of the sanctuary's current patients and residents, Jax, a male who was hit by a car, and new arrival Daisy.

Veterinary surgeon Donald Hudson said this was the relatively quiet time, with 15 patients.

"We expect to have double or triple that number this summer," Dr Hudson said.

The cost of caring for injured and orphaned koalas is offset by contributions from another part of the complex, with "glamping" accommodation, a cafe and an elevated walkway, which allows visitors to see the animals in the enclosures.

James Cook, the sanctuary's marketing and promotions manager, said bookings during the September school holidays had been very strong, as people looked for a COVID-safe holiday destination.

"We've been inundated," Mr Cook said.

Port Stephens Mayor Ryan Palmer said the sanctuary had been "a long time coming".

"There's certainly a need for it, when you saw koalas being cared for in laundries and bedrooms of residents of Port Stephens," said Cr Palmer. "So to go from a laundry to a facility like this, if I was a koala, I'd say it was a huge improvement."

Ron Land said while the sanctuary was an important part of koalas' future, it was not "the total panacea".

"What we've got to do is bring a major change in government attitudes to loss of habitat, and there has to be significant funding given to organisations like mine, to carry out the necessary work that we need to do," Mr Land said.

He also believed the NSW government should review koalas' conservation status, declaring the species endangered, instead of vulnerable.