The reaction by DBP, owned by DUET (60%), Alcoa (20%) and Alinta (20%), was in response to the authority’s final decision about access arrangements on the pipeline from 2005 to 2010, released yesterday.

As part of its decision, the regulator said it was in the public interest to drop gas standards in the pipeline, following supportive submissions by gas producing giants BHP Billiton, North West Shelf and Apache Energy.

Dampier Bunbury Pipeline executive chairman, Stuart Hohnen, reacted angrily to the decision and said the move now threatened expansion plans for the pipeline.

“The regulator’s decision on gas standards in unprecendented and flies in the face of the previous regulatory decision for the DBNGP as far as gas quality is concerned,” Hohnen said.

“The ERA’s move into this area injects regulatory uncertainty for the owners of the pipeline in the long term.”

He said the pipeline was paid according to the amount of energy transported. Therefore, lowering the quality meant that more volumes of gas would be needed to produce the same amount of energy.

In addition the economic regulator says the third-party access proposals by DBP did not meet the national gas access code covering the country’s pipeline industry.

The regulator, Lyndon Rowe, told The Australian that the capacity of the pipeline and known expansions were fully occupied by existing contracts.

Tariff reviews are not due again until 2016, with independent advice telling the authority that changing gas specifications would not materially impact the pipeline’s capacity. But Rowe said the owners could still renegotiate the specifications on commercial terms.

The Dampier-to-Bunbury pipeline, which runs from the North West Shelf to Bunbury, is Australia’s biggest pipeline system. It was sold by the Western Australian Government for $2.4 billion.