Activity Summary
The Barossa Gas Export Pipeline (GEP) is a 262 kilometre long, 26-inch diameter pipeline that will connect the Barossa field to the Darwin Pipeline Duplication (DPD). Together these pipelines will transport natural gas from the Barossa field to the DLNG plant.
The GEP pipeline route was carefully selected to minimise impacts to the surrounding marine environment.
The pipeline will be made from carbon steel with an external anti-corrosion coating and concrete covering to weigh it down on the seabed. It will be installed in water depths ranging from 254 metres at the northern end to 34 metres at the southern end. The pipeline has been designed and engineered in accordance with stringent international standards and to withstand the weather and currents that occur in the area. The pipeline will be installed and operated in a similar way to the other subsea pipelines currently in the area that have been operating safely for many years and supply gas to Darwin.
The pipeline installation is a low-impact activity involving the laying of pipe on the sea floor. There are no dredging or trenching activities.
Figure 1: The Barossa Project and the Gas Export Pipeline (red)
How will vessel activity be managed?
Santos is aware of other marine users along the pipeline route and broader Darwin region and has planned its activities to minimise impact to those marine users. Santos has engaged with marine users, has arranged preactivity briefings and will provide weekly updates and a communication plan to active marine users. Weekly updates will commence two weeks prior to the offshore installation to keep marine users abreast of vessel movements and other activities. As is usual with offshore construction activities, a Notice to Mariners will be provided for the construction and pipeline vessel for the protection of all seafarers. Santos and Allseas are committed to ensuring the rights and activities of other marine users are not unduly compromised.
Figure 2: Subsea Audacia pipelaying vessel
Approvals process
The Commonwealth Government’s independent expert regulator for offshore oil and gas development, National Offshore Petroleum Safety Management Authority (NOPSEMA), accepted the Barossa Offshore Project Proposal (OPP) in March 2018. The OPP is the government’s project-level environmental approval for offshore projects, with construction and operations subject to acceptance of activity-level environment plans (EPs). An EP:
- must provide a detailed environmental impact and risk assessment of the proposed offshore activity and demonstrate how those impacts and risks will be reduced to a level that is as low as reasonably practicable and acceptable for the life of the activity; and
- must describe how Santos has identified and consulted with relevant persons whose interests, functions and activities may be affected by the activities to be carried out under the EP.
The Barossa Gas Export Pipeline EP was accepted by NOPSEMA in March 2020 following a full and complete consultation process and it continues to be in place. All matters identified by stakeholders during the process were addressed.
Your feedback and what's next
On 13 January 2023, Santos received a general directed from NOPSEMA under requirements in Part 11A of the Offshore Petroleum and Greenhouse Gas Storage (Resource Management and Administration) Regulations 2011. Santos is undertaking further work to address the requirements of this direction relating to the potential for underwater cultural heritage places along the pipeline route.
As is usual practice, Santos is following the procedures in the approved Environment Plan and implementing the General Direction.
Visit santos.com/barossa for more information, phone 1800 267 600, or email offshore.consultation@santos.com
GEP installation weekly updates
Weekly updates for the GEP installation will be available here.