The information below is taken from the Supplementary EIS for the Carmichael Coal Project (GHD Pty Ltd, 2013).
Water is considered to belong to one of five categories:
- raw water – received from an external water supply as an input. Raw water is considered clean and has not been used in a task
- mine affected water (MAW) – has been through a task and is potentially contaminated by mining activities
- sediment affected water – contains higher sediment load but is not contaminated by mining activities
- clean water – runoff from undisturbed areas of catchment. This will be diverted around the project and is not part of the project water balance
- treated water – has been treated on site to achieve a particular water quality objective. MAW and raw water can be treated to allow for further use or released as a controlled discharge
- process water – used on site to complete a task.
126.96.36.199.1 Raw water
Raw water will be delivered and temporarily stored in a raw water dam.
188.8.131.52.2 Mine affected water
MAW water is generated from areas of active mining. This includes: dewatering of six open-cut pits; dewatering of five underground mines; dewatering three box cut areas of underground mines; dewatering two highwall access areas; the coal handling and preparation plant (CHPP) tailings decant dam and runoff from industrial working areas (such as MIA, ROM coal area, CHPP and the train load out facility).
MAW will be retained on site and stored in MAW dams. When necessary MAW will be discharged to receiving waterways under the mine’s approval conditions. The aim is to only discharge during extreme climatic events that exceed the design parameters.
184.108.40.206.3 Sediment affected water
Sediment affected water is generated from disturbed areas not contaminated with coal or other mining contaminates (such as areas disturbed due to vehicle movements or overburden areas). Sediment affected water will be treated to achieve minimum reductions in key pollutants before being reused or released to the natural environment.
220.127.116.11.4 Clean water
Clean water is diverted around mine workings or disturbed areas and released downstream into the same waterway. Mine workings are protected from local stormwater and regional flooding.
18.104.22.168.5 Treated water
Acid mine drainage water will be treated in through a neutralisation process in sediment basins or MAW dams.
Product Finalisation date
- 2.1.1 Geography
- 2.1.2 Geology
- 2.1.3 Hydrogeology and groundwater quality
- 2.1.4 Surface water hydrology and water quality
- 2.1.5 Surface water – groundwater interactions
- 2.1.6 Water management for coal resource developments
- Currency of scientific results
- Contributors to the Technical Programme
- About this technical product