New research led by Flinders University is renewing calls to protect the source of water and aquifers supporting the ecologically significant Doongmabulla Springs Complex in central Queensland from a proposed Carmichael coal mine in the Galilee Basin.
Activist group, Defend our Water, says the Doongmabulla Springs complex is a system of 160 separate wetlands which act as rich and ancient oases in a very dry landscape. The Great Artesian Basin springs are located just to the west of the proposed mine. The group says the springs have exceptional cultural significance to the Wangan and Jagalingou people. The Wangan and Jagalingou Council said in June 2019 that the decision of the Queensland Government to approve Adani’s ground water management plan imperils their sacred Doongmabulla springs.
As work on the Bravus (previously Adani) mine progresses, leading groundwater scientists warn that more research is needed to measure and fully understand the hydraulic pressure on the possible aquifer sources that feed the spiritually and ecologically important springs.
“Even if the spring’s source aquifer is partially dewatered for mining operations, there is a serious threat of permanent damage,” says Flinders University PhD candidate Mr Robin Keegan-Treloar, the lead author of a new paper in the Journal of Hydrology.
“Our study expands on existing water level data, perhaps in the most rigorous analysis so far, and even now we cannot definitively identify the source of water to the springs.
“While the Triassic Formations are more likely to have adequate hydraulic head to support spring flow, significant uncertainty exists in the conceptual model assessment due to hydraulic head measurement scarcity, particularly in the vicinity of the springs of this nationally (DIWA) important wetland,” Mr Keegan-Treloar says.
Despite previous warnings, and remaining uncertainties over the effects of nearby mining operations, the mine is still going ahead, says senior author, Flinders University Professor Adrian Werner, from the National Centre for Groundwater Research and Training.
“These findings have important implications given that the Permian Formations will be dewatered by the operation of the nearby Carmichael coal mine,” Professor Werner says.
The research group says the techniques used in the latest study help to identify and quantify conceptual model uncertainties for further research efforts. The group is doing follow-up studies using water chemistry, geophysics and numerical modelling at the site.
The paper, Application of Indicator Kriging to hydraulic head data to test alternative conceptual models for spring source aquifers (2021) by Robin Keegan-Treloar, Adrian Werner, Dylan Irvine (CDU) and Eddie Banks has been published in the Journal of Hydrogeology (Elsevier), Vol 601 October 2021 DOI: 10.1016/j.jhydrol.2021.126808
Cover image shows Dylan Irvine measuring the salinity of spring discharge and Flinders University PhD Robin Keegan-Treloar transcribing his measurements.. Photo Flinders University.