Activity 8: Proposals for using coal seam gas water in the Central Condamine Alluvium
In this guide:
- Coal seam gas water feasibility study
- Activity 1: Chemistry, origins and hydrogeology of coal
- Activity 2: Modelling and forecasting of coal seam gas water production
- Activity 3: Assessment of the salinity impacts of coal seam gas water
- Activity 4: Stream ecosystem health response to coal seam gas water release
- Activity 5: Vulnerability of aquifers to coal seam gas water extraction
- Activity 6: Aquifer injection feasibility
- Activity 7: South West Queensland water demand analysis
- Activity 8: Proposals for using coal seam gas water in the Central Condamine Alluvium
- Activity 9: Proposals for coal seam gas water use in the QMDB
The objective of activity 8 was to develop and assess specific proposals for using CSG water to address water sustainability issues in the Central Condamine Alluvium. Proposals involving aquifer injection and groundwater substitution were examined. Groundwater substitution refers to the use of treated CSG water in lieu of groundwater drawn from the CCA under a water entitlement. Injection refers to the transfer of treated CSG water into the CCA aquifer by means such as pressurised injection wells or gravity-fed infiltration ponds.
Activity 8 was delivered as three sub-activities:
- 8.1: Infrastructure options for delivering CSG water
- 8.2: Field program design for injection trials
- 8.3: Assessment of proposals for CSG water use
Activity 8.1: Infrastructure options for delivering coal seam gas water to the Central Condamine Alluvium
This activity investigated the physical infrastructure requirements for delivering CSG water for use via injection and/or substitution in the Central Condamine Alluvium. Pipeline routes and indicative capital and operational costs were identified for a range of scenarios encompassing different supply and delivery areas. These scenarios were developed in consultation with key stakeholders.
Activity 8.2 builds on the findings and recommendations of Activity 6.1, which has conducted a desktop analysis to identify the most appropriate locations and techniques for both shallow and deep injection into the Central Condamine Alluvium.
It should be noted that the State Government currently has no plans to undertake injection trials or implement a long-term injection scheme in the Central Condamine Alluvium. However, the assessments in this activity are designed to inform a business case for further consideration of CSG water management options.
Activity 8.2 prioritised the deep and shallow injection sites identified in activity 6.1 and designed a field program for undertaking injection trials to confirm the feasibility of injecting treated CSG water into the Central Condamine Alluvium. The activity also developed indicative designs for shallow and deep injection sites under a fully implemented injection scheme.
Activity 8.2 was conducted in two phases:
- The final Phase 1 report (PDF, 15.0MB) presents the method and results of the injection site prioritisation, as well as a conceptual design for an injection trial field program in the Central Condamine Alluvium.
- The final Phase 2 report (PDF, 6.1MB) presents the detailed field program design for injection trials as well as indicative designs for a injection sites under a fully implemented injection scheme.
Activity 8.3 built on other Activity 8 work to investigate more fully the use of CSG in the Central Condamine Alluvium. It consisted of three sub-activities.
Activity 8.3A examined in detail the issues associated with implementing the substitution components of any injection/substitution scheme in the Central Condamine Alluvium. The findings of this activity fed into activity 8.3C.
The activity 8.3B final report assessment of alternative use options for coal seam gas water proposed for Central Condamine Alluvium recharge schemes (PDF, 3.4MB) compared the CSG water use schemes proposed in activity 8.1 with alternative uses for the same CSG water in order to identify relative benefits, costs and feasibility issues.
The assessment of options for using coal seam gas water in the Central Condamine Alluvium business case (PDF, 7.1MB) developed in activity 8.3C examined suitable governance arrangements for implementing and operating a substitution/injection scheme in the Central Condamine Alluvium. The report also reports on additional work on modelling the response of the aquifer to such a scheme.