Code of practice for CSG well integrity
The Code of Practice for Coal Seam Gas Well Integrity establishes a best practice framework which includes:
- Mandatory standards for well design and construction to ensure the environmentally sound, safe production of coal seam gas and the protection of groundwater resources;
- Well monitoring and maintenance;
- The management of back flow or 'produced' water from the coal seam gas (CSG) extraction process;
- The design of all CSG wells guarantees the safe and environmentally sound production of gas by:
- Preventing any interconnection between coal seams and aquifers;
- Ensuring that gas is contained within the well and associated pipework and equipment without leakage;
- Ensuring isolation between different aquifers and water bearing zones;
- Not introducing substances that may cause environmental harm; and
- Requiring all chemicals used to be disclosed during the approvals process.
It is a mandatory requirement of the Code that the well design guarantees all fluids produced from the well travel directly from the production zone to the surface without contaminating groundwater.
Well construction, which takes up to a month, involves the insertion of steel casings around which cement is pressure injected to adhere to the surrounding rock.
The wells are then tested under very high pressure to establish there are no leaks.
Download Code of Practice for Coal Seam Gas Well Integrity, September 2012 (3.67 MB PDF)