A spokesman for offshore regulator NOPSEMA said Santos on Sunday reported gas bubbles were seen on the ocean surface 20 metres from the platform.
He said Santos evacuated the platform,which lies in Commonwealth waters,as a precaution and depressurised and shut in the 50 kilometre-long gas pipeline to Varanus Island.
The regulator understands that a vessel with gas detection equipment has detected no further gas.
The NOPSEMA spokesman said Santos told it there was a low likelihood the environment would be affected. The regulator has commenced an investigation.
“The pipeline will remain shut in until the source of the leak has been confirmed and integrity of the pipeline can be safely restored,” he said.
Santos told the stock exchange on Tuesday morning that the leak from a flange on the main gas pipeline from the platform to Varanus Island is expected to take four to six weeks to repair to allow a return to full production.
The loss of production from the 17-year-old platform started just before the WA’s south-west power grid that stretches between Kalbarri,Albany and Kalgoorlie faces two days of higher air conditioning use with maximum temperatures in the mid to high-30s predicted for Perth on Tuesday and Wednesday.