262 km pipelay almost complete off north coast of Australia

Major offshore pipeline specialist Allseas has achieved a major milestone in its installation work for Santos' Barossa gas field development off the northern coast of Australia.

After nearly a year's delay due to legal issues, Santos says the critical installation of the 262-kilometre Barossa natural gas pipeline is almost complete.

One of the key components of the Barossa Export Pipeline Engineering, Procurement, Construction and Installation (EPCI) Contract awarded to Allseas back in 2019 was the installation of a record-sized PLET - the end or termination of a pipeline.

Massive piece of kit

Allseas reported in an announcement this week that its specialist pipelaying vessel "Audacia" has now successfully installed her largest-ever PLET in S-mode, concluding several years of in-house engineering, fabrication and testing.

The pipeline end termination structure is so heavy, production crew had to install it separately to the connector head. It is so tall and wide, it only just fit through the tensioners and over the vessel's stinger.

That operation is a major part of the final stages of the installation of the Barossa gas pipeline, which was severely delayed by legal challenges from Tiwi Islanders.

Barossa back on target

Speaking at Santos' annual general meeting on April 11, chairman Keith Spence told shareholders pipelaying is nearing completion, while CEO Kevin Gallagher said the Barossa gas project itself is more than 70% complete.

Spence also revealed that the first Barossa well has been completed, with initial flow rates in line with expectations and carbon dioxide content at the low end of the expected range.

Santos is currently drilling the second of six Barossa wells.

Installation of the project's subsea facilities installation is well under way, while 13 of the 16 topside modules have now been installed on the floating production storage and offtake (FPSO) vessel.

The Barossa LNG project is designed to utilise existing infrastructure at Darwin LNG to deliver a new supply of gas to Japan and Korea.

At full production rates, Barossa is expected to add 1.8 million tonnes per annum to Santos' LNG portfolio.

Gallagher also noted that Santos continues to pursue its Bayu-Undan carbon capture and storage project, which would safely and permanently store up to 10 million tonnes of CO2 per year, including CO2 from the Barossa gas project.

Source: Energy News Bulletin