Australia's offshore energy regulator has issued a formal warning to Santos over compliance failings at its flagship Barossa gas development, according to leaked correspondence obtained by ABC News Business.
The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) cautioned the nation's second-largest oil and gas producer following site inspections of the multi-billion-dollar offshore venture in the Timor Sea.
Inspection findings spark safety scrutiny
The communication from the safety and environmental watchdog outlined specific deficiencies identified during regulatory reviews, noting that Santos must address operational vulnerabilities before advancing critical project stages.
While NOPSEMA routinely monitors major energy infrastructure across Commonwealth waters, the formal nature of the warning reflects deepening scrutiny over the gas giant's execution of complex offshore operations.
According to the ABC report, the regulator's correspondence highlighted compliance matters related to safety systems and project standards, underscoring ongoing friction between resource companies and environmental authorities over statutory obligations.
Santos has maintained that it operates within regulatory parameters and continues to work constructively with authorities to meet all mandatory criteria.
Contentious timeline for Timor Sea asset
The Barossa development, situated approximately 300 kilometres north of Darwin, represents one of the largest capital commitments in the Australian resources sector this decade. With an estimated capital expenditure exceeding $5.8 billion, the project is designed to backfill the Darwin liquefied natural gas facility as existing reserves at the Bayu-Undan field deplete.
However, the venture has encountered relentless hurdles since its inception. Work on the field was previously halted following successful Federal Court challenges brought by Tiwi Islands Traditional Owners, who argued that Santos had failed to adequately consult their communities on potential risks to marine habitats and cultural heritage.
While Santos subsequently secured refreshed approvals and resumed drilling and subsea pipeline works, the latest regulatory warning threatens to inject fresh uncertainty into the project's commissioning schedule, which targeted first gas by 2025.
Environmental battles and investor focus
Barossa has also drawn fierce resistance from climate advocacy groups and institutional investors, who point to the reservoir's unusually high carbon dioxide content. The field contains roughly twice the proportion of reservoir carbon as other regional developments, making it among the most carbon-intensive gas fields in Australasia without substantial carbon abatement.
Santos has pledged to mitigate these emissions by implementing a carbon capture and storage scheme at the depleted Bayu-Undan reservoir, though that companion initiative remains subject to its own cross-border regulatory approvals between Canberra and Timor-Leste.
Regulatory pressure mounts across offshore sector
The leaked findings come amid broader regulatory tightening across Australia's offshore basins. NOPSEMA has significantly hardened its posture in recent years, issuing enforcement notices and demanding higher standards of evidence regarding safety cases and environmental mitigation.
With Santos balancing investor demands for disciplined capital returns alongside high expenditure on major developments, any operational revisions ordered by the regulator could exert pressure on project margins. For now, market attention remains focused on whether the company can resolve NOPSEMA's concerns without sustaining further timeline slippage on its premier growth asset.