The company responsible for the Timor Sea oil disaster expects to make another attempt to plug the leaking Montara well head on Monday and says if successful oil could stop flowing into the sea within hours of the intercept.
Oil has been flowing untapped into the sea from the stricken West Atlas rig, 250km from the Kimberley coast, for the past seven weeks at a rate estimated to be around 400 barrels a day.
So far attempts to plug the leak have failed.
The company, the Thai based PTTEP Australasia, says it is preparing to intercept the well head and plug a 25cm hole more than 2.5km under the sea bed.
It expects to drill into an area within five metres of the hole by Monday and plug the leak with heavy mud.
"Members of the leading international oil and gas well control engineering specialists ALERT Well Control boarding team are on standby at Truscott air base in the Kimberley while a Perth-based boarding team is on standby and ready for travel to the site when the intercept is successful," the company said in a statement today.
"The team leader from ALERT Well Control is on board the West Triton directing the sophisticated electro magnetic ranging and intercepting equipment. This technology has been used successfully in similar operations around the world."
Meanwhile conservationists are becoming increasingly concerned at the time taken to plug the leak.
The stricken rig is in an area recognised as a highly fished section of the Northern Demersal Scalefish Fishery and a major target of that fishery red emperor are scheduled to start spawning within days.
John Carey from the Pew Environment Group said his group found it difficult to believe assurances from the company that the leak would be plugged any time soon.
"Despite the assurances and talk of world best practice this leak keeps going on and on. We are constantly told it will be fixed but we find it difficult to believe," Mr Carey said.
The massive oil slick is drifting around 160km off the West Australian coast and is 205km from the the coast of Indonesia. It is around 50km from the environmentally sensitive coral atolls, Ashmore Reef and Cartier Reef.
Coral spawning is scheduled to take place on October 11 and scientists have previously expressed concern that the slick and dispersants used to send the oil to the bottom of the sea could interfere with the success of the spawning event.