ABC News Homepage
You may or may not have heard of the Great Artesian Basin, but there is a good chance you've eaten or worn something produced with its water.
Australia's largest groundwater system covers more than 1.7 million square kilometres across Queensland, New South Wales and South Australia.
Millions of sheep and cattle graze across the basin, and hundreds of regional communities rely on it.
Coal giant Glencore is seeking approval to store waste carbon dioxide (CO2) from a Queensland carbon capture and storage project in a Great Artesian Basin aquifer, and it has fired up just about everyone.
Queensland's Conservation Council oppose it, so do farmers and all the peak state and federal agriculture bodies, and even pro-coal MP Colin Boyce is against it.
Glencore says the project is "based on robust scientific fieldwork", but a report it commissioned found that even "food grade" CO2 could cause levels of lead and arsenic in the groundwater to rise to hundreds of times the safe drinking water guidelines.
The company insists "it does not risk agricultural or town drinking water".
The carbon capture and storage project is a relatively small trial, in a very deep underground aquifer, and the Independent Expert Scientific Committee says "impacts are expected to be minimal and manageable in both the immediate and long term."
But with other carbon capture and storage projects reportedly being planned in the GAB, there are concerns about the precedent the CTSCo project might set.
So should Australia's most significant underground water resource be used for food production or to store waste CO2?
What is CTSCo?
Glencore is one of the world's biggest coal miners, and through its subsidiary Carbon Transport and Storage Corporation (CTSCo), is planning a trial of capturing CO2 from a coal-fired power station in southern Queensland and injecting it deep underground.
CO2 will be captured from the Millmerran Power Station, turned into "supercritical fluid", and then trucked north to a storage well near the farming town of Moonie, more than 400 kilometres west of Brisbane.
Over the three-year trial, CTSCo plans to inject up to 110,000 tonnes of the waste CO2 each year into the Precipice Sandstone aquifer, a groundwater formation in the Great Artesian Basin, which is about 2,300 metres underground.
CTSCo general manager Darren Greer told the ABC in 2021 the trial could determine the future of carbon capture storage in Australia.
"It's essential this project works, this will not just be the reference case for our project scaling up, but it will ultimately be the reference case for other people to capture and store CO2," Mr Greer said.
"That's why doing this project properly, and doing it responsibly and getting right is essential today because if we do it wrong, it'll be even harder for the next people to do it."
CTSCo is still waiting for final environmental approval.
Agriculture v big coal
The National Farmers' Federation and Queensland's AgForce took out full-page ads in major newspapers this month to voice their growing concern about the carbon capture storage project's potential effect on the Great Artesian Basin.
They have called for the federal environment minister to revoke a decision made by the previous government that the project was "not to be a controlled action under national environment law as it is unlikely to result in a significant impact on nationally protected matters".
"The court of public opinion wouldn't accept this if it was with the Great Barrier Reef or Sydney Harbour," AgForce's Michael Guerin said.
AgForce has also started fundraising for a potential legal battle should the project be approved.
CTSCo has called the commentary from the National Farmers' Federation irresponsible and misleading.
"Despite calling on the government to listen to the experts, the [National Farmers' Federation] is ignoring the scientific data and relying on alarmist rhetoric to intimidate regulators," a CTSCo spokesperson said last year.
Could farmers be affected?
CTSCo says its project is based on robust scientific fieldwork, data and analysis, and that there are no predicted impacts on existing or future groundwater users.
General manager Darren Greer said the groundwater at the site was non-potable, and had fluoride levels six times above the safe drinking water level.
He said it was not used by any of the agricultural community within a 50km radius.
But farmer Ken Cameron, who runs a major piggery less than 10km from the CTSCo project lease, said he had a licence to drill a water bore into the same aquifer that CTSCo would use to store CO2.
"The fluoride levels and salinity of the water we're currently using of shallower aquifers, they're higher levels than the water in the samples they took … so it's a total nonsense," he told the ABC last year.
"Their proposal is to pump industrial waste into the Great Artesian Basin, and the Great Artesian Basin is the lifeblood of much of regional Australia."
Mr Greer said the project did not risk agricultural or town drinking water.
"The injected CO2 will form a plume 2.3km underground ... this plume will stay in proximity to the injection point and water quality outside this plume is unlikely to change," he said.
"Monitoring and verification will be carried out both during and after CO2 injection to ensure that the groundwater beyond the site is not impacted.
"We believe that [carbon capture storage] is an essential emission reduction technology that can be deployed without impacting groundwater used by community and agricultural producers."
Isn't it 'food grade' CO2?
Initially, CTSCo claimed the aquifer in the Great Artesian Basin where it planned to store the captured CO2 was saline and unsuitable for agriculture.
However, its water samples showed the water was within official livestock water quality guidelines.
In recent statements, CTSCo has described the CO2 as food grade like the CO2 found in soft drinks.
But food grade or not, hydrogeologist Ned Hamer said CTSCo's own investigation found that the injected CO2 would cause the acidification of the groundwater.
"This CO2 injection will reduce the natural groundwater pH from 8.35 down to 4," Mr Hamer said.
He said it would have a significant effect on the groundwater.
"Given pH units are a logarithmic scale, this equates to a greater than 10,000 times increase in acidity of groundwater," Mr Hamer said.
Mr Hamer has been subcontracted by some of the landholders opposed to the CTSCo project, but has also worked in this part of the Great Artesian Basin for almost 30 years.
Report authors and other hydrogeologists familiar with the project have declined to provide comment to the ABC.
Acidic groundwater
Acidic water can dissolve underground rock and release carcinogenic heavy metals such as cadmium, arsenic and lead.
The University of Queensland's Centre for Natural Gas released a report in October last year that tested the potential for metal mobilisation in groundwater at the CTSCo site.
The report was commissioned by the Australian National Low Emissions Coal Research & Development, a proponent of carbon capture and storage.
Using drill core samples from the aquifer where CTSCo wants to store waste CO2, modelling in the UQ report found that the injected CO2 "plume" and the associated acidification of the groundwater could raise the levels of lead and arsenic significantly.
"This acidic plume will dissolve the aquifer rock resulting in the release and mobilisation of heavy metals at concentrations hundreds of times greater than the human and stock drinking water guideline levels," Mr Hamer said.
"These metals will remain dissolved and migrate within the aquifer for more than 100 years."
Mr Greer insisted that the groundwater was non-potable.
"It is important to note that the precipice groundwater at this location already contains the trace element fluoride, at levels six times above the safe drinking water level," he said.
Mr Hamer has previously told the ABC that fluoride was common in the Great Artesian Basin and was relatively easily removed from and treated from a groundwater supply if needed.
Hasn't the CSIRO ticked off on this?
The Intergovernmental Panel on Climate Change (IPCC) and the International Energy Agency (IEA) have acknowledged the role that carbon capture and storage can play as the world transitions away from burning fossil fuels.
The CSIRO has also published a report examining Australia's "significant geological storage potential" for the storage of waste CO2 "in geological basins", including the Great Artesian Basin.
In response to criticism of its Queensland carbon capture and storage trial, CTSCo has consistently stated that the project has been independently reviewed by the IESC, Office of Groundwater Impact Assessment (OGIA) and CSIRO as part of the environmental impact statement process.
But some of the findings from the expert bodies weren't definitively supportive of the project.
The IESC, or Independent Expert Scientific Committee review "expected" potential impacts would be minimal and manageable.
It also flagged potential impacts from the project that required further consideration.
"Limited site-specific data have been used to develop the models relied on by the proponent to predict plume behaviour and potential impacts from the project," the report said.
"Changes to groundwater quality in the Precipice Sandstone aquifer, within the GHG plume extent, which may have implications for future usability."
At the request of Queensland regulators, the CSIRO has also reviewed the CTSCo project, and found that CTSCo "assumes that potential impacts due to future development of groundwater extraction in the Precipice Sandstone are not possible for economic reasons".
Meaning, the aquifer was over 2km deep, and it would be expensive for private landholders to drill a bore to access the groundwater.
"Potential impacts on water users in the Precipice Sandstone aquifer due to new groundwater extraction near the GHG (Greenhouse Gas) stream injection well cannot be ruled out," the CSIRO report found.
CTSCo said it had accepted the recommendations and amended its environmental impact statement.
"The project incorporates an extensive monitoring network to verify the location of the injected CO2 along with groundwater quality changes," Mr Greer said.
"Monitoring and verification will be carried out both during and after CO2 injection to ensure that the groundwater beyond the site is not impacted."
What's at stake?
Annually, Great Artesian Basin water produces "at least $12.8 billion" worth of production, and many regional towns and communities rely on its underground water.
The CTSCo project concerns a small section of one aquifer in a vast underground water system, and while it could have some localised impacts, it will not suddenly pollute the rest of the Great Artesian Basin.
Not all parts of the basin are usable due to high levels of sodium and other salts, and the aquifer being targeted by CTSCo is very deep and would be very expensive to access.
CTSCo said it understood and respected the importance of the Great Artesian Basin to the Australian agricultural community.
But opponents of the project such as Queensland MP Colin Boyce are more worried about the precedent that would be set if waste CO2 were allowed to be pumped into the unique and valuable water resource.
"Why on earth would you compromise a potable water source in Australia, the world's driest habitable continent," he told the ABC last year.
No comments:
Post a Comment