The whistleblower who raised the alarm about environmental damage and contamination at the failed Linc Energy underground coal gasification (UCG) project in southern Queensland says toxic chemicals will continue to spread from the site.
Queensland's Department of Environment and Science (DES) has rejected reports that landholder water bores near the site at Hopeland, about 300 kilometres west of Brisbane, have been contaminated by chemicals such as cyanide and benzene.
It said since 2021, four samples had been taken from groundwater monitoring bores installed about 650 metres west of the boundary of the former Linc Energy site.
The department acknowledged the samples showed the presence of underground coal gasification contaminants benzene and cyanide, but said nearby landholder's water bores had not been affected.
"The analysis of the four samples indicates that the concentration of contaminants is trending down, and the likelihood of environmental harm arising is considered very low to negligible," a DES spokesperson said.
However, the ABC has seen leaked department documents that show some groundwater monitoring bores recorded benzene and cyanide levels up to 25 and 11 times respectively above safe drinking water guidelines.
Benzene is a chemical produced by both natural and industrial processes such as oil and gas extraction, and it's a carcinogen that is toxic to both humans and animals.
Cyanide is a substance found in combination with naturally occurring chemicals in the environment, which is very toxic to humans and animals.
Both benzene and cyanide are also by-products of UCG, which involves setting fire to underground coal seams, and capturing the resulting "syngas" at the surface through wells.
Between 2000 and 2013, with the backing of both the Beattie and Bligh state Labor governments, private company Linc Energy operated an experimental UGC project on prime farmland west of Brisbane.
But it was shut down after it was found the company had mismanaged the underground burning of coal seams at the plant, causing the release of contaminants such as benzene and naphthalene into the soil, air, and groundwater.
Extensive damage to groundwater
Ray Cowie worked as a petroleum engineer for Linc Energy, and was one of the original whistleblowers who alerted authorities to the environmental damage. He said it was likely the contamination would continue to spread.
"We did extensive modelling … and predicted that this would happen and, over time, will actually get worse," Mr Cowie said.
As the water table at the site naturally recharges, he said it would likely transport contaminants into neighbouring water bores.
"Just think of the bathtub — when you pull your plug out of the bathtub, everything draws towards the bunghole," he said.
Mr Cowie claimed that Linc Energy overheated and over-pressurised the coal seams, which caused fracturing of the geology and opened up pathways for the toxic by-products to be spread beyond the site.
"This damage was extensive, out 10, 20, 30, 40, 50 kilometres – that's how bad it is," he said.
Brian Bender, who farms at Hopeland near the former Linc Energy site, said communication from authorities had been poor.
"It all comes from the media first and the landholder needs to be the first one informed," Mr Bender said.
"It's just the unknown unknowns, and we just need the things to settle … we need everything — full disclosure from all parties."
The Queensland state opposition has called on Environment Minister Meaghan Scanlon to provide an explanation of the situation.
"This is one of the worst environmental disasters our state has seen, and the minister has quite clearly failed in her responsibilities to Queenslanders," said shadow environment minister Sam O'Connor.
"Minister Scanlon is accountable for this cover-up and must explain her actions."
However, in a statement Ms Scanlon disputed the allegation.
"When I became aware of reports that adjacent landholders had only been provided with results from bores on their properties, I directed the department to provide advice on the contamination found," she said
"Any suggestion by the LNP of a cover up by me is absolute nonsense."
And in a response to a question in parliament in August 2021, Ms Scanlon did in fact publicly acknowledge that benzene and cyanide had been detected at levels beyond safe drinking limits outside the former Linc Energy site.
Mr Bender said any further planned activity near the old Linc Energy site, such as Arrow Energy's plans to drill 55 news coal seam gas wells, should be halted until there were clear answers.
"We just need to let things rest for a number of years," he said.
A DES spokesperson said in a statement that results from its monitoring program had been provided directly to landowners, most recently in late 2021.
It said it rejected any suggestion that it had failed to comply with the notification requirements contained in the Environmental Protection Act 1994.
The DES said it was conducting a full and robust assessment of Arrow Energy's plans to drill near the site, and Arrow Energy had been advised of the results of the groundwater bore monitoring program.
