However, it is another wake-up call for the two companies involved – Origin Energy and drilling contractor, Century Resources – who suffered the worst onshore drilling diaster in decades in April 2003 when one man died and two other seriously hospitalised in an uncontrolled blowout lasting a week on the Myall Creek-8 in Queensland.

Whilst performing a routine wireline survey, the company said gas flowed up the drill pipe before blow out preventers could be closed. Yesterday it said gas and water were still being vented to the atmosphere. A water deluge system had arrived on site to minimise the risk of ignition.

Meanwhile a 5 kilometre ‘no fly’ zone has been established around the site – south east of the Dongara township.

Origin spokesman Wayne Gregory told EnergyReview.Net that four Century Drilling employees did receive minor burns and were taken to hospital as a precaution. He said three were already back at work while the fourth has been replaced as part of a normal shift rotation.

He said a procedure was being developed to re-establish control of the well, which was expected within 24 hours.

A Department of Industry and Resources investigation is expected. An extensive safety check of Rig 24 was carried out some months ago so while the physical condition of the rig is probably in good shape it does throw a significant question over management systems.

Participants in L11 and Tarantula-1 are Origin Energy Developments (Operator) 67% and ARC Energy Limited 33%.