Federal government agencies are under scrutiny for their handling of a significant methane leak linked to gas company Santos. This leak, which has reportedly released thousands of tons of methane since the Darwin Liquefied Natural Gas (DLNG) plant began operations in 2006, was revealed by recent reports. Environmentalists have condemned the situation as a "national scandal" after it was disclosed that Santos has been permitted to continue using a faulty storage tank until 2050 without addressing the leak or measuring emissions.

The Clean Energy Regulator and the Commonwealth Scientific and Industrial Research Organisation (CSIRO) provided advice to Santos regarding the leak, but details of this guidance have not been made public. The Clean Energy Regulator stated it has no record of any advice given to Santos, despite the company notifying the agency about the leak via email in 2020. In contrast, CSIRO, which Santos engaged as an independent expert, has declined to release records of its advice, citing concerns that doing so could harm its commercial interests.

The revelations have prompted criticism from several senators, including David Pocock and Monique Ryan. Federal Greens leader Larissa Waters has called for an auditor-general review, questioning whether the situation reflects a failure of regulatory oversight or a deliberate cover-up to protect Santos's profits. Waters has also reached out to federal ministers to address the apparent inaction by the Clean Energy Regulator and to inquire about CSIRO's financial ties to Santos.

An email obtained through a Freedom of Information request shows that after Santos took control of the DLNG in May 2020, the company sought guidance from the Clean Energy Regulator regarding a spike in estimated emissions from the leak. Santos reported that drone surveys indicated methane emissions of 832 tons per year, exceeding its previous reports under the National Greenhouse and Energy Reporting scheme. However, the Clean Energy Regulator claimed that no documents related to this inquiry exist, despite extensive searches.

The estimated methane leak is significant, equating to more carbon emissions annually than nearly one in four companies that reported to the Clean Energy Regulator for the 2023-24 period. Documents obtained under FOI also reveal that Santos paid CSIRO for advice on addressing the leak. A Northern Territory Environmental Protection Authority officer noted in a November 2020 email that the engagement with CSIRO was a positive outcome, aligning with previous recommendations.

However, CSIRO has refused to disclose details of its research, arguing that releasing such information could jeopardize its future commercial opportunities. The agency stated that its work was conducted on a commercial basis and that sharing the findings could harm its competitive position in the market.

Waters has called for transparency regarding Santos's payments to CSIRO for its advice on the methane leak. In her correspondence with federal minister Tim Ayres, she expressed concern over the lack of action taken by CSIRO to mitigate the leak and urged for the release of all financial agreements with Santos. Additionally, she has questioned Climate Change Minister Chris Bowen about the Clean Energy Regulator's actions concerning the ongoing methane leak and its implications for national greenhouse gas accounts.

The Northern Territory Environmental Protection Authority has indicated that the leak does not pose an immediate threat to the community or environment, stating that addressing the issue is a commercial decision for Santos. While the agency acknowledges the environmental impact of methane emissions, it maintains that regulatory oversight falls under the Clean Energy Regulator's jurisdiction. Santos has asserted that the tank is safe for use until 2050 and that it complies with all relevant regulatory requirements.