Code of practice for coal seam gas fracture stimulation
All CSG drilling additives must be tested by a National Association of Testing Authorities-certified laboratory and demonstrated to meet Australian drinking water health guidelines.
The Code of Practice for Coal Seam Gas Fracture Stimulation (599 KB PDF) establishes a best practice framework that covers:
- The hydraulic fracturing process;
- The use of chemicals in fracturing fluid;
- The sourcing of the water using in fracturing; and
- the protection of aquifers from the fracturing fluid.
To protect groundwater, surface water and the environment, the NSW Government has banned the use of harmful chemicals, known as BTEX, used interstate and overseas in hydraulic fracturing operations.
The new controls stipulate all CSG drilling additives must be tested by a National Association of Testing Authorities-certified laboratory and demonstrated to meet Australian drinking water health guidelines.
Samples of drilling additives and fracture stimulation additives may be taken at any time by the EPA to verify compliance.
To avoid any impact on water resources and to keep the fractures within the targeted area, each fracture stimulation must include:
- Identification of the rock types, the condition of aquifers and their distance from the target coal seams;
- Determination of the faults and stresses in the surrounding geology and the maximum pressure that can safely be applied; and
- Identification of the intervening strata and their porosity and permeability.
The Code also stipulates a risk assessment must be made before each fracture stimulation of the effects on public safety, land contamination, air pollution, noise and vibration, loss of well integrity, induced ground movements or seismicity and conflicts with existing land uses.