Gold producer Regis Resources said it was exploring legal options after a rare federal protection order blocked its $1 billion NSW project on cultural heritage grounds.

The company told investors on Thursday it would write down $192 million on its McPhillamys Gold Project site in central-west NSW after the shock decision last week by Environment Minister Tanya Plibersek.

Chief executive Jim Beyer also dismissed her comparison on Thursday of the potential damage of the mine's tailing dam on significant cultural areas of the Belubula River, to Rio Tinto's 2020 destruction of ancient rock shelters at Juukan Gorge in WA's Pilbara.

Mr Beyer said the company was not giving up on developing the gold mine, after the government's declaration in support of an application by the Wiradyuri Traditional Owners Central West Aboriginal Corporation – which lists only 18 members – ignoring views of the recognised Traditional Owners the Orange Local Aboriginal Corporation, which did not oppose the dam.

"We continue to assess all legal options available to respond to this decision," he said on Thursday.

Regis told investors Ms Plibersek's Section 10 protection order rendered the project "unviable" in its current form and came despite the NSW Independent Planning Commission in 2023 approving the company's mining application.

Ms Plibersek on Thursday said Wiradjuri Traditional Owners asked her to protect the headwaters and the springs of the Belubula River as they had held significance for thousands of years.

"It's associated with the time that young people move to adulthood and a number of the creation stories of the Wiradjuri people," she said.

"In 2020, when Juukan Gorge was destroyed, we said as a nation that we shouldn't allow the destruction of Aboriginal cultural heritage in this way ever again."

Mr Beyer rejected the Minister's claims the tailings dam would cause damage to the river.

"The bigger concern is that it is after years of work, testing, surveying for heritage, drilling, investigations, expert advice, state and federal approvals and spending hundreds of millions of dollars, a decision can be made, overturned," he said.

"If there's one thing the country needs, it's consistency."

The decision would cost the local community and business in the long run, with almost 1000 jobs now killed off.

"It's quite stressful for a lot of people," Mr Beyer said.

His frustration was also felt by industry lobby group Association of Mining and Exploration Companies, which felt the order lacked "reason and commonsense".

"It sets a truly terrible precedent for investment risk in Australia," CEO Warren Pearce said.

"The $1 billion investment to build the mine, the 580 construction jobs, the 290 operational jobs, and $200 million dollars of royalties to the State, as well as real benefits for local Traditional Owners, just went up in smoke."

Opposing groups WTOCWAC and OLALC declined to comment on the decision.