Coal seam gas water

Coal seam gas (CSG) water is a by-product of CSG production. It is water that has been extracted from coal seams in order to release coal seam gas. CSG water contains varying concentrations of salt.

CSG water management
CSG Water Management Policy
CSG Water Management Policy amendments
Beneficial use approvals
Regulated structures including dams
Salt and brine
Evaporation dams
Coal seam gas recycled water
Coal seam gas water feasibility study

CSG water management

The department has developed the CSG Water Management Policy to protect the environment and promote ecological sustainable development as described in the Environmental Protection Act 1994.

To undertake a CSG activity, operators must apply to the department for an environmental authority, which is a licence that regulates the potential environmental impacts of the activity.

As part of the application process, CSG operators are also required to submit environmental management plans which demonstrate how they plan to manage CSG water. The environmental management plan must include information about CSG water, such as:

the flow rate, quantity and quality of CSG water expected to be generated
proposed management, including use, treatment, storage or disposal
criteria against which the CSG operator will monitor and assess the management of CSG water
proposed actions taken by the CSG operator should any management criteria not be satisfied.

CSG operators are also required to submit an annual evaluation of how effective and appropriate management of CSG water has been. For example, the management of CSG water by the operator may include a water treatment facility and irrigation of the water for dust suppression. The annual evaluation would provide information about the quality of the CSG water including that used for dust suppression, the results of any tests of the water treatment facility or failures of the facility, and any impacts on environmental values. If it is determined that CSG water has not been appropriately managed, the CSG operator will need to outline actions to ensure appropriate management in the future. The department can also amend the environmental approval to ensure that the water is managed properly.

Read more information on CSG Water (PDF, 144K)*

CSG Water Management Policy

The CSG Water Management Policy June 2010 (PDF, 160K)* outlines the preferred and non-preferred management options for CSG water. The policy also sets out a hierarchy for management and disposal of salt.

CSG water is a by-product of the production of coal seam gas. It is drawn from the coal seam in order to enable the gas to be released and captured.

The Coal Seam Gas Water Management Policy June 2010 clearly states the Queensland Government’s intent on how CSG water should be managed.

The policy provides guidance to applicants and decision-makers on CSG water management options that are to be considered as part of a CSG activity.

The CSG Water Management Policy lists injection and beneficial use as the two preferred management options for CSG water. Discharge to streams and evaporation dams are non-preferred uses.

CSG Water Management Policy amendments

In late 2011 the government sought feedback on a draft Coal Seam Gas Water Management Policy (PDF)* and supporting documents. The draft policy amended the Coal Seam Gas Water Management Policy June 2010 and established aquifer injection and beneficial use as the priority water management options for coal seam gas (CSG) water. Public feedback on the draft policy was sought between 24 November and 23 December 2011.

The draft CSG Water Management Policy is now being reviewed to ensure that it is in line with the policies of the new Queensland Government. Public submissions made in 2011 will also be considered as part of this review.

The CSG Water Management Policy June 2010 (PDF, 160K)* will remain in effect until this review process is finalised.

Beneficial use approvals

CSG water is defined as a waste under the Environment Protection Act 1994. It must be disposed of under the conditions of an environmental authority, or beneficially used under a beneficial use approval. A beneficial use approval changes the status of the material from a waste to a resource and the holder of the approval must manage it in a way that minimises the risk of environmental harm.

There is one general approval related to coal seam gas activities for which anyone can benefit, provided that the conditions of the approval are met.

The Decision to approve a resource for beneficial use – Associated Water - EM35 (PDF, 122K)* outlines the requirements for the beneficial use of coal seam gas water for aquaculture, coal washing, dust suppression, industrial and manufacturing operations, irrigation and livestock watering.

Where the conditions of this general approval cannot be met, it is possible to apply to the department for a specific approval. Applications for a specific approval will be assessed in accordance with s. 160 of the Waste Reduction and Recycling Act 2011. The guideline Approval of coal seam gas water for beneficial use (PDF, 285K)* gives guidance on applying for a beneficial use approval for coal seam gas water.

Regulated structures including dams

The department has changed the way it assesses dams or levees in planned CSG activities for potential hazards, such as failure or collapse, which may cause environmental harm.

The new requirements for assessing the hazards of dams or levees, referred to as regulated structures, are outlined in the below manual and guideline.

CSG companies applying for an environmental authority must demonstrate via certification from a Registered Professional Engineer of Queensland that the design and construction of their regulated structure meets the hazard assessment requirements.

The guideline also contains a range of ‘model’ conditions that provides performance requirements set by the department including the requirement for CSG operators to maintain a regulated dam register. Obtain a template for a regulated dam register (Excel, 1.5M)‡.

This risk management approach requires the resource industry to actively manage a regulated structure throughout its life.

Salt and brine

Coal Seam Gas (CSG) water is a by-product of CSG production and typically contains significant concentrations of salt. It is classified as a waste under the Environmental Protection Act 1994.

The salinity of CSG water is typically measured as the concentration of total dissolved solids (TDS) with values ranging from 200 to more than 10,000 milligrams per litre.

By comparison, good quality drinking water has TDS value of less than 500 milligrams per litre. The TDS of sea water is between 36,000 and 38,000 milligrams per litre.

The treatment of CSG water results in the following waste streams, which must be

managed:

waste water with a higher concentration of salts
solid salt left behind after this water evaporates
salt contaminated material (e.g. the lining of a dam that contained CSG water) and
brine from any advanced waste water treatment of CSG water. Brine is defined as saline water with a total dissolved solid concentration greater than 40,000 milligrams per litre.

Management and disposal

Unless CSG water is reinjected into the coal seam, or used in an environmentally acceptable way, it must be treated to a standard defined by the department before disposal, or before being supplied to others to be used for a beneficial purpose.

The management of waste products must be authorised by an environmental authority issued under the Environmental Protection Act 1994. The department requires CSG operators to demonstrate that waste management proposals have considered the most acceptable solution first, before considering less acceptable solutions.

Find out more about salt and brine management (PDF, 142K)*.

Evaporation dams

In all but exceptional circumstances, evaporation dams have been banned for coal seam gas (CSG) water, and existing dams will be either converted to other uses or decommissioned. Strong standards have also been introduced for coal seam gas water dams.

Read more about coal seam gas water dams (PDF, 145K)*

Coal seam gas recycled water

Amendments to the Water Supply (Safety and Reliability) Act 2008 established purpose-built, rigorous requirements relating to the production and supply of treated CSG water to an urban community’s drinking water supply source.

Read more about the regulation for CSG recycled water.