Southern Queensland farmers say a lack of data could leave them without recourse if a new $10 billion coal seam gas scheme causes their productive cropping land to subside.
- Queensland farmers say a $10 billion coal seam gas project has potential to cause highly productive farm land to sink
- Landholders say an absence of ground-level data could mean they will have no recourse if CSG causes their properties to subside
- Gas company Arrow Energy says that modelled CSG-related subsidence will be “imperceptible compared to natural variation and variability”
Concerned farmers near Cecil Plains, 200 kilometres west of Brisbane, are facing off against Arrow Energy, a gas company approved to drill up to 2,500 gas wells over 8,600 square kilometres, from Wandoan to near Goondiwindi.
Their multi-billion dollar Surat Gas Project is a 27-year operation, and it is in phase one.
Under Queensland law, landholders are obliged to negotiate with gas companies who own the right to the resources under their land. But Dalby farmer Mark Schurrs was pushing back
“This is essentially the gas industry’s first foray into really high-quality ag land,” Mr Schurrs said.
Arrow Energy has plans to put gas wells and pipelines across his farm on the Condamine flood, an area known for its productive clay, loam soils.
Farmers on the Condamine floodplain said they were worried that when gas and water was extracted, the ground may subside.
Zena Ronnfeldt’s property adjoins an Arrow Energy owned property, and there are gas wells all around their boundary.
Already she has concerns about possible subsidence in the vicinity of a gas well that was drilled over 10 years ago, metres from one of their paddocks.
“On our side of the boundary we’ve got a spot that was always wet, but now we’ve noticed that it’s holding water and being quite a lot wetter over the last two years,” Ms Ronnfeldt said.
“When we’ve gone to the gas company to ask that question, what we’ve found is, they don’t actually have the data that we expected them to have given the requirements of their environmental authorities and approved plans.”
Arrow Energy has investigated the Ronnfeldts’ issue. It said, after a comparison of historical aerial photos and recent drone images, “ground movement due to CSG has not occurred to the extent it has altered drainage on the property.”
The company said it would continue to monitor ground levels in line with its approvals.
Arrow Energy shared its report on the issue with the Ronnfeldts in February 2021.
“Arrow has prepared a report based on a comprehensive study of data dating back to 2012,” a spokesperson said.
Concern about future impact of CSG
To determine possible future impact of CSG extraction on the environment, Arrow energy is required to establish baseline data.
But the Ms Ronnfeldt questions the accuracy of the interferometric synthetic aperture radar technology (InSAR) being used to monitor ground movement.
In 2018 Arrow Energy commissioned a report that found the technology produced “a low density of reliable interpretations.”
An Arrow Energy spokesperson said it was improving the accuracy of its baseline data.
“Arrow has been working with the specialists who process the InSAR data, which has resulted in an 85 per cent increase in the amount of data provided,” the spokesperson said.
Arrow Energy also said it was using additional methods of collecting data, including Light Detect and Ranging (LiDAR), a laser and light detection technology, as well as aerial photography and on-ground sensors.
The issue for the Ronnfeldts is that in Arrow Energy’s approvals there is no baseline data for their farm.
Arrow Energy said it had thorough ground-level monitoring data.
“Based on modelling and experience, Arrow predicts CSG-related subsidence to be relatively even and widespread and imperceptible compared to natural variation and variability,” a spokesperson said.
“Arrow will continue to update and refine modelling predictions in line with monitoring observations.”
Not all farmers oppose CSG
The coal seam gas industry has been operating for over 20 years in Queensland, and there are thousands of gas wells on properties and thousands of contracts between gas companies and landholders.
Landline has spoken to a number of farmers who are happy with the industry. Some farmers who host gas see it as an opportunity to complement their business.
Farmers who host gas are compensated, and the GasFields commission said contracts with gas companies could provide an additional income stream.
The roll out of the Surat Gas Project will be a new test in striking the right balance between farming and mining.