The Wilderness Society has launched legal action challenging the environmental approval granted to Norwegian energy giant Equinor to explore for oil in the Great Australian Bight.

The conservation group had flagged a possible court case after the proposal to deepwater drill in the Great Australian Bight Marine Park was approved by the federal offshore petroleum regulator in December. It was the second, and most significant, of four regulatory hurdles Equinor needs to clear before it can drill.

Peter Owen, the Wilderness Society’s South Australian director, said Equinor had refused to formally consult affected groups as required. He said the National Offshore Petroleum Safety and Environmental Management Authority, known as Nopsema, had made a legal error in accepting the company’s claims that it had.

Great Australian Bight: Norwegian energy company Equinor given environmental approval to drill for oil Read more

Owen said the decision effectively dismissed the concerns of environment groups representing tens of thousands of members, Indigenous custodians with cultural values threatened by offshore drilling and more than 20 local governments responsible for communities and coastal property as not relevant to the approval process.

“We should all be very concerned about the precedent Equinor and Nopsema have set here,” he said. “We have no doubt that if Equinor had fully and legally consulted with these parties, its plans would have been better informed and more robust. Instead, it is our view that it now holds an invalid approval.”

Equinor declined to respond, saying it was not appropriate to comment on a matter before a court. The company has previously said its plan shows drilling can be done safely and it had been preparing its proposal for two and a half years, including more than 400 meetings with community and other organisations.

It was granted a petroleum title over areas in the bight in 2011. The proposed Stromlo-1 well site is in water more than 2.2km deep and nearly 400km off the South Australian coast. Nopsema said it had approved the plan after a rigorous assessment that took almost eight months. Equinor still needs a well operations plan and a facility safety case approved before it can begin drilling.

The regulator said it had imposed stringent conditions on its approval, including limits on the time of year activity can take place and regular public reporting on environmental impact, to ensure a high level of protection that reflected the bight’s uniqueness.

Drilling in the Great Australian Bight is not worth the risk | Rick Steiner Read more

It had earlier asked Equinor to modify and resubmit its environmental plan to provide more information on its consultation with affected groups and on the risks posed by oil spills. An analysis based on an amalgamation of 100 oil spill simulations found there was potential for a spill to spread along the coastline and into the ocean between Esperance in Western Australia, Sydney and Tasmania.

Equinor’s plans have sparked protests that organisers say have been supported by tens of thousands of people across Australia. Owen said polling suggested a majority of Australians opposed the project.

The conservation group’s federal court action is supported by Indigenous elders and Holdfast Bay council. Bunna Lawrie, an elder of the Mirning people, the traditional owners of the bight, said he feared drilling would lead to oil spills that poisoned the sea and affect whales.

The council’s mayor, Amanda Wilson, said it was disappointed Nopsema had not considered its concerns about the potential economic and environmental impact of an oil spill, particularly on Glenelg. “Our 11km of pristine white sandy beaches in Holdfast Bay are a major drawcard for visitors and our local community, and it’s our duty to protect them,” she said.

If approved, Equinor plans to begin work late this year, with the operations expected to last between 30 and 60 days.