2.6.2.5.1 Open cut mines


The five baseline coal mines are: Cameby Downs Mine, Commodore Mine, Kogan Creek Mine, New Acland Coal Mine Stage 2 and Wilkie Creek Mine (which ceased operations in December 2013). The two proposed coal mines in the CRDP are: New Acland Coal Mine Stage 3 and The Range. Table 5 summarises the open-cut coal mines modelled in the Maranoa-Balonne-Condamine subregion.

Table 5 Open-cut coal mines modelled in the Maranoa-Balonne-Condamine subregion

In this table, results are presented for only that part of the coal resource development pathway (CRDP) that can be modelled.


Project name

Company

Tenement(s)

Timeline

Mine pit area (ha)

Target seam depth (m BGL)

Estimated water extraction (ML/year)

Comments

Cameby Downs Mine

Yancoal Australia Ltd

ML 50233

Baseline

(2010–2055)

15

50–60

36.5

Operating mine

Commodore Mine

InterGen Australia Pty Ltd and Marubeni Corporation / Downer EDI Mining

ML 50151

Baseline

(2002–2032)

40

70–80*

no data available

Operating mine

Kogan Creek Mine

Aberdare Collieries Pty Ltd

ML 50074

Baseline

(2007–2018)

100

70–80

140–150

Operating mine

New Acland Coal Mine Stage 2

New Hope Group

ML 50170, 50216

Baseline

(2002–2017)

55

30–60

110–150

Operating mine

Wilkie Creek Mine

Peabody Energy Inc

ML 5908, 50208, 50214, 50215

Baseline

(1994–2013)

20

no data available

no data available

Mine closed

New Acland Coal Mine Stage 3

New Acland Coal Pty Ltd

MLA 50232

ACRD

(2015–2029)

75*

50–80*

180–1280

Mine expansion subject to approval

The Range

Stanmore Coal Limited

MLA 55001

ACRD

(2014–2041)

50*

60*

150–490

Approved mine

ACRD = additional coal resource development, BGL = below ground level, ML = mining lease, MLA = mining lease application, * = estimated

A conservative approach is used to simulate mine pit dewatering to account for the relatively coarse regional-scale model grid (1.5 km × 1.5 km grid cells). The MODFLOW Drain package is used to set the boundary conditions in the model cells corresponding to the mine pit footprints. For each mine, OGIA and the Assessment team used publicly available information to delineate the extent of operational and proposed pits, referred to as mine footprints, to represent coal mines in the revised OGIA model (Table 5). All model grid cells intersected by operational and proposed pit extents are assumed to be part of the modelled open-cut coal mine. The model grid cells for each of the modelled operational and proposed mine pits are shown in the insets in Figure 9.

It is assumed that mine pits are dewatered to the depth of the coal seams to enable coal mining operations. This is represented in the groundwater model by activating and deactivating the Drain cells to replicate the modelled development timeline shown in Figure 10. The Drain cell elevation in the Walloon Coal Measures model layer (Layer 10) is set to either the mean coal seam depth or, if the mean coal seam depth is below the bottom elevation of the model cell, then the Drain cell elevation is set to the bottom of the model grid cell. This means that the groundwater model draws the groundwater level down over the entire model grid cell where a pit is present and does not adjust for the proportion of the grid cell covered by the actual pit area. This approach may tend to overestimate groundwater drawdown associated with open-cut coal mine pit dewatering.

Last updated:
17 October 2018
Thumbnail of the Maranoa-Baloone-Condamine subregion

Product Finalisation date

2016
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