APIA's executive director, Dr Allen Beasley, said the Draft Code on Pipeline Decommissioning would add to the existing APIA Environmental Code, which covers pipeline design, construction and operation.

"It is essential that this industry takes a whole of life view on the environmental impact of transmission pipeline development and use," Dr Beasley said.

"Australia now has over 20,000km of high pressure gas transmission pipelines and while the average age of these assets is relatively young, the industry must begin to contemplate the possibility of decommissioning pipelines in the future."

The Draft Code emphasises the need to assess both the environmental and commercial costs and benefits of a range of decommissioning strategies which may include the suspension of pipeline operations for a period of time, abandonment in place and pipeline removal.

"When a pipeline is no longer required due to depletion of gas reserves, changed markets, substitute pipeline services or for safety reasons, it is essential that the pipeline be decommissioned in an environmentally responsible manner," Dr Beasley said.

"This draft Code sets out the key options and environmental measures that must be considered and addressed in the decommissioning process," he said.

Dr Beasley said APIA was seeking submissions and comments from all interested stakeholders and that State Governments would be consulted on the draft document.