Impacts of coal seam gas extraction on water resources in Australia

1. Impacts of coal seam gas extraction on water resources in Australia Extraction of coal seam gas may impact on water resources and water related assets through changes in the quality and/or quantity of surface water and/or groundwater. A $43 m program of research titled Bioregional Assessments has been set up to examine these possible impacts in Australia. David Post CSIRO, Canberra, Australia FURTHER INFORMATION David Post Senior Principal Research Scientist, CSIRO edavid.post@csiro.au p +61 2 6246 5751 Objectives The objectives of the bioregional assessments are to: understand the hydrogeologic and flow regimes of a bioregion prior to future CSG and coal mining development understand the state and natural variation of key water-dependent assets located in the bioregion undergoing CSG and coal mining development understand the characteristics of the target CSG and coal resources and hence the likely techniques, and associated water volumes, involved in their extraction. Progress The Bioregional Assessment Programme commenced in July 2013. Work to date has focused on: creating an overall methodology setting out the key steps involved in carrying out a bioregional assessment1 gathering key datasets and writing context statements summarising current conditions and previous research in the bioregions creating water-dependent asset registers containing important ecological, economic and social assets deriving a methodology for attaching measurable receptors to assets creating a development pathway containing the most likely development of coal mining and coal seam gas development developing a conceptual model of causal pathways linking the impact of the stressor to the water-dependent asset. Next steps Work from here will focus on: developing and running numerical surface water and groundwater models to explicitly represent the impacts of depressurisation and disposal of co-produced water determining the impacts of CSG and coal mining on water-dependent assets as measured through the identified receptors. In doing this, we will: Explicitly assess direct, indirect and cumulative impacts Identify all sources of model and parameter uncertainty and quantify the propagation of uncertainty through the programme Carry out the entire study through the lens of risk analysis in order to be able to quantify the associated risks and uncertainties. Figure 1:Location of the bioregions being assessed Figure 2:Flow chart summarising the Bioregional Assessment methodology REFERENCES 1 Barrett DJ, Couch CA, Metcalfe DJ, Lytton L, Adhikary DP and Schmidt RK (2013) Methodology for bioregional assessments of the impacts of coal seam gas and coal mining development on water resources. A report prepared for the Independent Expert Scientific Committee on Coal Seam Gas and Large Coal Mining Development. Department of the Environment, Australia. www.environment.gov.au/coal-seam-gas-mining/pubs/methodology-bioregional-assessments.pdf