Long-hidden methane leak in Darwin raises fresh doubts over Australia’s climate action
- Written by Melissa Haswell, Professor of Health, Safety and Environment, School of Public Health and Social Work, Queensland University of Technology
Environment groups have called for federal intervention following revelations an LNG export hub in Darwin has emitted large volumes of methane from an LNG storage tank since 2006.
The ABC on Monday revealed years of failures to address the leak. State and federal authorities reportedly approved Santos’ controversial 25-year Barossa offshore gas project without requiring the leak to be repaired or replaced.
The incident adds to serious doubts about whether Australia can meet its commitment to reduce emissions of methane, a highly potent greenhouse gas.
The vital pledge will only be met if governments and industry prioritise climate action and human health over profits.
What happened in Darwin?
The Darwin case demonstrates dangers of relying on industry to assess and manage risks to the climate and human health.
The leak involved an enormous above-ground tank which contained highly processed methane derived from LNG (liquified natural gas).
According to the ABC, the leak was caused by a design flaw. The reports said the tank’s original owner, ConocoPhillips, discovered the leak in 2006 and reported it to the Northern Territory’s Environmental Protection Authority (EPA), describing the emissions as “minute”. The tank held gas for the next 18 years.
Two measurements using drone technology, in 2019 and 2020, reportedly indicated the leak was bigger than initially thought – up to 184 kilograms of methane was leaking per hour. This was not reported to the EPA until months later, according to the ABC.
Gas giant Santos now operates the tank, which is now reportedly empty. But it’s set to be filled again, as part of Santos’ Barossa gas project.
The ABC says state and federal regulators have not forced Santos to repair or replace the tank, adding:
They and the company say the leak is stable, and poses a moderate climate risk but no immediate threat to the public or the environment.
Santos told the ABC regulatory approvals and an ongoing monitoring program were in place, and the company reports its greenhouse gas emissions annually.
Methane: a major climate culprit
Methane is a dangerous greenhouse gas which drives about 30% of global warming. While it does not last in the atmosphere as long as carbon dioxide, its ability to trap heat is potent. In fact, methane is about 86 times more harmful than carbon dioxide (CO₂) in global warming terms, when measured over two decades.
Aside from the harms caused by escaped methane, the leak also represents an enormous waste of a substance produced at a very high cost to the climate. Natural gas extracted from the ground is transported to processing plants and liquified for export, by cooling it to about -160°C. This is an extremely energy-intensive process which itself is powered by natural gas and creates substantial greenhouse gas emissions.
Methane reduction is considered a crucial step towards averting a climate disaster. The International Energy Agency says methane abatement from oil and gas operations offers some of the world’s best opportunities to cut emissions – was also likely to give companies a commercial advantage.
In 2022, Australia signed the Global Methane Pledge, a non-binding commitment to reduce methane emissions by 30% by 2030. Australia’s energy producers also claim they are committed to reducing methane emissions in Australia.
The Darwin methane leak reveals a host of problems with gas regulation in Australia – including a lack of public transparency issues with the methods used to quantify leaks. These problems undermine industry and government pledges to reduce emissions.
A health time bomb
Bushfires and backburning already pollute the air around Darwin.
What’s more, the neighbouring Inpex LNG plant in Darwin has also consistently released huge amounts of highly toxic substances including hydrogen sulphide, nitrogen oxides and volatile organic compounds.
Methane adds to the problem. It reacts with other chemicals in the atmosphere to form a dangerous air pollutant known as “ground-level ozone”.
Research has found each year, ground-level ozone contributes to up to 1.4 million deaths globally, from respiratory and cardiovascular disease.
Tropical areas immediately adjacent to cities, such as Darwin’s outer suburbs, are most at risk from such pollution.
Environment Centre NT has also expressed fears the leaking methane presents an explosion risk.
A challenge exposed
The problem of methane emissions is not confined to gas projects. For example, research earlier this year showed methane emissions from an open-cut coal mine in Queensland were up to eight times higher than reported annually by the operator.
And the problem is not confined to Darwin. Methane-emitting fossil fuel projects are proliferating across Australia. Recent approvals include expansion of Woodside’s Northwest Shelf gas project and numerous coal mines.
What’s more, Australia does a poor job of measuring and reporting methane emissions.
Australian governments and their agencies must get serious about acting on climate change. This includes efforts to rapidly curb methane emissions – while also dramatically cutting CO₂ emissions.
No industry in the world carries more power to secure the planet’s future than the fossil fuel operators. Together, industry and governments must stop fuelling our demise.
Authors: Melissa Haswell, Professor of Health, Safety and Environment, School of Public Health and Social Work, Queensland University of Technology
