The objective of the injection modelling project was to evaluate the ratio of coal seam gas (CSG) water to natural flow over a period of sixteen years in the Precipice Sandstone aquifer at Spring Gully.
The project involved predictive modelling of the injection of the injection of CSG water, with the application of a FEFLOW groundwater model. The model was developed under three base case scenarios; Best-Estimate, Maximum Impact and Minimum Impact which were associated with specific target aquifer parameters. The model development required boundary conditions and pre-injection steady state conditions to be quantified. The model also addressed particle tracking and head contour development over a period of five hundred years.
For each of the scenarios, the injection well injects for 16.5 years whilst the public supply boreholes pump continuously for 1,000 years. The head rise at the injection site was contoured at the end of the injection.
This project was based on the regional APLNG EIS groundwater model of the Surat Basin constructed by Worley Parsons (2010) and the groundwater model developed by KCB in 2011.
- Updating existing regional groundwater models
- Predicting best estimates of hydraulic impacts
- Long term groundwater modelling