Groundwater dominates discussion at Adani court case

AN expert has spent an entire day talking about dirt.

Dirt, groundwater, mapping, modelling and sampling to be accurate.

Hydrogeologist John Bradley was in the witness box for about five hours on Wednesday talking about how he assessed groundwater systems and geology in the Galilee Basin, where the Carmichael Mine is proposed.

Environmental group Coast and Country is taking mining company Adani to court over its Carmichael Mine.

The group has objections about how the mine would impact climate change and the Great Barrier Reef and questions whether the project was financially viable.

But Wednesday's focus was about groundwater.

The environmental group claims the mine poses risks to groundwater and nearby springs that form part of the Great Artesian Basin. It also alleges Adani had not properly assessed the mine's impact on groundwater.

This was why Mr Bradley was quizzed under cross examination for an entire day on his assessment of groundwater systems.

Barrister Saul Holt from the Environmental Defender's Office, representing Coast and Country, asked Mr Bradley about seismic assessments that are used to determine the risk of cave-ins and collapses during mining process.

Mr Bradley said from his assessment there was no evidence of faulting around the Doongmabulla Springs area, which Coast and Country believe to be a million years old.

But under cross examination, it was revealed that he did not ask for any seismic data.

"I don't disagree that that information would be valuable," Mr Bradley said. "But I made my assessment based on data that is available within the (mine's) lease area."

Mr Bradley said he used information that was available to him, including data from drilling samples.

But Mr Holt continued to quiz him, saying there was no evidence of possible collapses and cave-ins because Mr Bradley hadn't asked for this information when carrying out assessments.

"I guess that's the point isn't it, if you don't look for something, it is necessary there would be no evidence of it," Mr Holt said.

But Mr Bradley disagreed.

"No my point was that you can tell a lot from drill holes," he said.

He explained seismic data was another way to look for "faults" underground.

The hearing at Queensland's Land Court continues on Friday.