2.3.1.2 Developing causal pathways

The systems summary (Section 2.3.2) for the Galilee subregion draws upon existing contextual information compiled as part of the BA (specifically companion product 1.1 (Evans et al., 2014) and companion product 1.5 (Evans et al., 2015) for the Galilee subregion) as well as the new understandings and interpolations presented in companion product 2.1-2.2 for the Galilee subregion (Evans et al., 2018). The hydrogeological conceptualisation presented in this product is a first for the geological Galilee Basin and demonstrates many features of the subregion, including how groundwater flow systems in the Galilee Basin could interact with aquifers in the overlying Eromanga Basin. Section 2.3.2 also highlights knowledge gaps and uncertainties in the conceptualisation of the subregion.

The conceptualisation of hydrological and hydrogeological systems provides the framework to assess if there is potential for effects from hazards associated with coal resource development activities to propagate through the hydrological systems.

A hazard analysis conducted for the Galilee subregion (Section 2.3.5.2) was based on information from the proposed CSG operations and coal mines (as outlined Section 2.3.4.1) and their water management plans (Section 2.3.4.2). The hazard analysis for the Galilee subregion was completed during a one-day workshop in March 2015 with experts from CSIRO, Geoscience Australia and the Department of the Environment.

Two workshops involving external stakeholders (including representatives from industry, and the Queensland and Commonwealth governments) were run as part of development of the conceptual models for causal pathways work for the Galilee subregion.

The first workshop was in October 2014 and focused on the development of the CRDP (Section 2.3.4). Outcomes of this workshop determined which developments outlined in Lewis et al. (2014) would be likely to commence within a reasonably forseeable (10–15 years) time frame. The results are presented in Section 2.3.4. A key outcome from the workshop was that no coal resource developments are included in the baseline for the Galilee subregion because there are no commercially operating coal mines or CSG fields as of December 2012 (See Section 2.3.1.1 and Figure 3).

The second workshop, held in August 2015 in Brisbane, focused on the conceptual models for the causal pathways. This workshop explored possible regional and cumulative hazards in the Galilee subregion that may connect a coal resource development activity to potential hydrological changes that may then affect water-dependent assets. Results and causal pathways are outlined in Section 2.3.5. The companion product 1.3 for the Galilee subregion (Sparrow et al., 2015) outlined water dependent assets situated in the Galilee subregion. This workshop outlined possible cumulative hazards that may occur at regional scale, rather than for specific coal resource developments in the Galilee subregion, and identified possible causal pathways that may link hazards and water-dependent assets.

One of the outcomes of the workshop is that causal pathways are not needed for the baseline because there are no coal resource developments in the baseline for the Galilee subregion.

A landscape classification (Section 2.3.3) was developed to characterise the nature of water dependency for assets identified in the companion product 1.3 for the Galilee subregion (Sparrow et al., 2015). The aim of the landscape classification is to systematically define geographical areas into classes based on similarity in physical and/or biological and hydrological character. The objective of the landscape classification is to present a conceptualisation of the main biophysical and human systems at the surface and describe their hydrological connectivity.

The landscape classes (Section 2.3.3) conceptually form the impact-receiving layer at surface and can potentially be connected via subsurface and/or surface hydrological pathways to hazards associated with coal resource development activities. Hydrological impacts from activities could propagate along connective pathways and induce a hydrological change to a landscape class at surface (Section 2.3.5.3). Within BAs, all modelling of potential ecological impacts is organised by and conditioned upon the landscape classes in a potential area of impact. Potential areas of impact are areas where hydrological changes due to coal resource development have been delineated through modelling outlined in companion product 2.6.1 (Karim et al., 2018) and companion product 2.6.2 (Peeters et al., 2018) for the Galilee subregion. Further detail on how landscape classes are utilised in the Galilee subregion is outlined in the receptor impact modelling (companion product 2.7 for the Galilee subregion (as listed in Table 2)).

Section 2.3.1.1, Section 2.3.5.1 and companion submethodology M05 (as listed in Table 1) for developing a conceptual model of causal pathways (Henderson et al., 2016) provide further detail on methods for developing conceptual models for causal pathways.

Last updated:
17 December 2018