2.6.2.3.1 Objectives

The numerical groundwater MODFLOW (Harbaugh, 2005) model aims at evaluating the impacts of the additional coal resource development on groundwater resources in the Richmond river basin of the Clarence-Moreton bioregion. The direct impact at every model node is represented by the difference of the drawdown between the coal resource development pathway (CRDP) and baseline (described in Section 2.6.2.5) and the time at which this drawdown is realised. This direct impact is mostly associated with model nodes associated with economic assets (bores) whose locations and screened aquifers are reported in companion product 2.1-2.2 for the Clarence-Moreton bioregion (Raiber et al., 2016a).

The model also provides predictions for the exchange fluxes between aquifers and surface water features, which is considered as an indirect impact. The exchange fluxes were reported as time series at 16 virtual gauges, which were subsequently incorporated into a surface water model to assess the indirect impact on other model nodes.