The West Australian mining watchdog has started legal proceedings against gas giant Santos over an oil spill that allegedly killed several dolphins off the state's Pilbara coast.
The Department of Energy, Mines, Industry Regulation and Safety (DEMIRS) alleges Santos did not operate its licensed pipeline in "a proper and workmanlike manner" to prevent the spill in March 2022.
DEMIRS alleges Santos did not operate its licensed pipeline in a proper manner by failing to prevent the escape of petroleum. (Supplied: Parliament of Australia)
DEMIRS said the spill was caused by a ruptured subsea hose connecting a tanker to Santos' Varanus Island gas plant.
About 25,000 litres of condensate, a light oil, poured into the Indian Ocean near the Lowendal Islands, about 300 kilometres west of Karratha.
In response to the spill, DEMIRS required Santos to strengthen the company's environment plan to reduce the risk of future incidents.
On Monday, after a multi-year investigation, DEMIRS announced it is also taking legal action against Santos.
"The benefits of resource extraction must not come at the expense of Western Australia's long-term environmental sustainability," said DEMIRS resource and environmental compliance executive director Tyler Sujdovic.
"The department will continue to work with industry and local communities to ensure resource projects strike the right balance between extraction and environmental stewardship."
The gas giant was ordered to retrieve one of the dolphin carcasses in the wake of the spill but failed to find them. (Supplied: Parliament of Australia)
The ABC has contacted Santos for comment about the legal proceedings.
Claims regarding the spill were aired in federal parliament last year, with independent Senator David Pocock tabling whistleblower testimony that accused Santos of covering up the deaths of at least three dolphins.
The Adelaide-based company has previously denied it is responsible for the dolphins' deaths or that it attempted to mislead the public about the extent of the spill.
Senator David Pocock used parliamentary privilege to publicise whistleblower testimony at a Senate estimates hearing. (AAP: Mick Tsikas)
Eight pictures and two videos were put before the estimates committee, along with allegations by a former employee that Santos failed to deploy a scientific monitoring team quickly enough to assess the spill's full impact.
At the time, Santos reported three dead dolphins to state authorities.
It has since said the carcasses were first spotted several hours before the spill.
The company was ordered to collect one of the carcasses for examination but failed to locate them again after two searches.
Regulating environmental harm
Santos commissioned an investigation into the 2022 incident which "did not support claims of a cover-up" and found the incident was "appropriately reported".
A copy of that report has not been made public.
DEMIRS will take Santos to court over a 2022 condensate spill. (Supplied: Parliament of Australia)
A review of DEMIRS, conducted by Auditor-General Caroline Spencer in the same year as the spill, found the department was not effectively enforcing environmental standards for mining projects.
The auditor-general pointed to two major players, which had violated regulations with little consequence besides a warning letter.
These were eventually revealed to be Rio Tinto and Fortescue.
"Their [DEMIRS] monitoring and enforcement … do little to deter operators from breaching conditions," the auditor-general wrote.
Since accepting the auditor-general's recommendations, between January 2023 and June 2024, DEMIRS has issued 109 letters of warning to mineral and petroleum projects, referring four for investigation.
The regulator also handed down 25 fines equating to about $660,000, according to its quarterly reporting for the same period.
Only three formal directions to modify operations were sent, all within the minerals sector, and not to petroleum sites.
Santos will face Karratha Magistrates Court for the first hearing on January 6, 2025.