The Bylong Coal Project is a proposed open-cut and underground coal mine located in the Upper Hunter Valley of New South Wales. The project occurs within the Sydney Basin and targets the Illawarra Coal Measures. AGE were engaged by Hansen Bailey environmental consultants, on behalf of KEPCO Bylong Australia Pty Ltd, to complete a groundwater study to form part of the Environmental Impact Statement.
The project occurs in a ridge area adjacent to a thin alluvial aquifer system that is utilised for agricultural purposes within the region. A key challenge was to understand the connectivity between Illawarra Coal Measures and Bylong River alluvial aquifer and to quantify potential impacts. To address this, KEPCO implemented an extensive field program to characterise these key groundwater systems. AGE used this data to gain an in-depth understanding of the hydrogeological regime and to develop a conceptual groundwater model. A numerical groundwater model was then developed to simulate natural groundwater processes and replicate system stresses including mining and bore abstraction to quantify potential changes due to the project. The outcomes included:
- quantification of groundwater take from the Bylong River water sources, for licensing purposes;
- predicted changes in water levels in the various aquifers, as well as the creeks and rivers; and
- assessment of impacts on key receptors, including private landholder bores and groundwater dependent ecosystems.
AGE also assisted responding to submissions on the project and engaging with key stakeholders including government and the community.