2.3.4 Baseline and coal resource development pathway

Summary

There are 42 mining operations in the baseline coal resource development (baseline) in the Hunter subregion, comprising 22 open-cut mines and 20 underground mines. These baseline mines are used to quantify the impact on regional hydrology of mines that were operating at December 2012. Some baseline mines are not included in the surface water and groundwater numerical modelling of the Hunter subregion (reported in companion products 2.6.1 (Zhang et al., 2018) and 2.6.2 (Herron et al., 2018b)) due to lack of data or because the models do not represent key processes influencing local hydrology.

Additional coal resource developments (i.e. those considered likely to commence production after December 2012) proposed for the Hunter subregion include 3 new open-cut coal mines, 3 new underground coal mines and 16 expansion projects of baseline mining operations at December 2012. Ten potential mining operations were deemed too uncertain to include as additional coal resource developments.

For the Hunter subregion, the mines in the baseline and those identified as additional coal resource developments define the coal resource development pathway (CRDP).

Mine water use in NSW is governed by various legislation, pertaining to protection of the environment and the extraction and use of shared water resources. This regulatory framework ensures that the mining industry prepares mine water management plans for each operation, which identify environmental impacts and provide options for minimising impacts; require licences for water extractions and discharges; and attach conditions to licences that protect the environment on- and off-site.

Based on the regulatory framework, some common assumptions can be made about mine effects on hydrology to inform bioregional assessment (BA) hydrological models:

  • All rainfall on the mine site is retained on site.
  • Extractions of water from groundwater and the river network must be licensed. Licences specify entitlement volumes.
  • An environment protection licence (EPL) is required to export mine water from the site. For mines along the Hunter regulated river, this is managed as a system of salinity credits through the Hunter River Salinity Trading Scheme (HRSTS). For mines that are not part of this scheme, discharge conditions are as required under their EPL.
  • Rehabilitation of mine sites is a condition of the mining licence. In open-cut mines, rehabilitation is progressive, but removal of surface drainage diversion channels occurs at the end of mine life.
  • Open-cut mines generally leave a final void, which means landscape runoff does not completely return to pre-disturbance conditions.

This section describes how coal resource development in the Hunter subregion will be addressed in the quantitative modelling. Section 2.3.4.1 identifies the mining operations that are included in the baseline and the CRDP. Section 2.3.4.2 presents how mine water management is generically represented in the modelling; therefore, water management by individual mines are not the focus here, but rather what assumptions can be made about the off-site effects of mine water management for representation in the quantitative models. Specific details of the parameterisation of mining operations for representation in the numerical models are provided in the surface water modelling (companion product 2.6.1 (Zhang et al., 2018)) and groundwater modelling (companion product 2.6.2 (Herron et al., 2018b)) for the Hunter subregion, and in data observations and statistical analyses (see Section 2.1.6 of companion product 2.1-2.2 (Herron et al., 2018a)) for the Hunter subregion.

Last updated:
18 January 2019