Methane bubbles in groundwater cast doubts over Beetaloo basin fracking approval, scientists say
Experts have cast doubt on groundwater studies that underpin the Northern Territory government’s decision to permit fracking in the Beetaloo basin, after methane bubbles were observed at hot springs in an area targeted for gas production.
In a new report, commissioned by the Environment Centre NT (ECNT), the scientists warn of “critical knowledge gaps” in baseline groundwater assessments conducted by the government in response to the Pepper inquiry into fracking.
Ninety percent of the territory’s water supply comes from groundwater while the territory’s hot springs support ecosystems and Indigenous cultural values.
“Our analysis shows that there are significant and critical gaps in the knowledge base underpinning fracking approvals in the Northern Territory,” said Matt Currell, a professor of environmental engineering at Griffith University and lead author of the report commissioned by the ECNT.
“This means that, at present, it is not possible to properly assess the risk of contamination and over-extraction of Northern Territory water due to fracking.
“Further studies are required to fill these knowledge gaps. To proceed on the current evidence base would be unwise, and may risk valuable aquifers, rivers and springs.”
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Of particular concern, the authors found the government had failed to properly determine where the groundwater that flows to important springs comes from. They said the baseline studies lacked clear data on potential connectivity between shallow and deeper aquifers.
The authors said the government had also failed to develop a thorough profile of water quality throughout the groundwater systems. This would help establish whether there was a risk that saline water found at deeper levels, for example, could contaminate freshwater at shallow levels.
Currell also pointed to studies at hot springs on Tanumbirini station – an area targeted by gas companies.
“The discovery of methane bubbling to the surface at hot springs is particularly concerning, as it suggests connections between the shale gas layer to be targeted for fracking and surface water,” he said.
“This could become a pathway for contamination of water relied upon by communities in the Northern Territory.”
A spokesperson for the NT environment, parks and water security department defended the studies which, combined with the fracking inquiry, had made the Beetaloo region “the most extensively studied in the Territory across land, water and biodiversity, with a comprehensive focus on water”.
In a letter to the NT environment minister, Lauren Moss, six environment groups urged the government to put further fracking approvals and finalisation of a water allocation plan for the Beetaloo region on hold until it addressed “16 critical knowledge gaps” identified in Currell’s report and had its baseline studies peer-reviewed.
“We have repeatedly been assured by the NT government that the science underpinning its decision to greenlight fracking is sound,” the executive director of the ECNT, Kirsty Howey, said.
“Now we learn that baseline water studies are slipshod and seriously flawed, with holes so big you could drive a truck through them.
“All fracking approvals and water allocations for fracking must be put on hold until the federal government ensures that the water trigger is in place, and baseline studies are completed and peer reviewed.”
The water trigger requires the environment minister to consider the impact of large coal and coal seam gas proposals on local water resources.
Djingili elder and director of Nurrdalinji Aboriginal Corporation, Elaine Sandy, said “we have a responsibility to protect water, for our communities and everyone living here”.
“If fracking damages our water it can never be put right,” she said.
The letter calls for activities to be put on hold until the NT government established water advisory committees for the Beetaloo region and the federal government expanded the water trigger under national environmental laws.
The Albanese government has promised to expand the water trigger to include the shale gas in the Beetaloo basin as part of environmental reforms that have been delayed until next year. The Greens and independent MP Sophie Scamps have introduced their own bills to pressure the government to act before the end of the year.
The NT government’s spokesperson said investigations, led by CSIRO, would continue on the Hot Springs Valley located on Tanumbirini Station.
The spokesperson said a summary that synthesised the findings of the baseline assessments had been externally reviewed by two experts who sat on the panel of the inquiry into fracking.
They said the dataset for the Beetaloo region would continue to grow as a result of monitoring through government programs and by petroleum companies operating in the region.