Chevron Australia has submitted plans to the National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) for the construction and installation of a pipeline at the company’s Gorgon Project in Western Australia.
Gorgon comprises offshore production wells and pipeline infrastructure that gathers natural gas from the Jansz–Io and Gorgon gas fields and transports it to a facility on Barrow Island for processing.
To support the reliability of the offshore gas gathering systems, Chevron Australia proposes to install an additional control and electrical umbilical to the existing feed gas pipeline system that extends between the offshore Gorgon field and the facility on Barrow Island.
Temporary power supply (e.g. via subsea batteries or a downline power cable) will be required during the transition from the use of the existing Gorgon umbilical to the additional control and electrical umbilical.
If power supply from the existing umbilical becomes unavailable prior to the commissioning of the additional control and electrical umbilical, a temporary power supply may also be utilised to maintain electrical power supply.
The Gorgon gas field is located within production licences WA-37-L and WA-38-L, ~130 km off the north-west coast of Western Australia (WA), and ~65 km north-west of Barrow Island.
The infrastructure to be installed under this Environment Plan (EP) will form part of pipeline licence WA-20-PL.
Chevron’s submission documents the assessment and management of potential environmental impacts and risks associated with the installation of the additional umbilical bundle and the supply of temporary power in Commonwealth waters.
The scope of activities includes:
- Installation
- Inspection, maintenance and repairs
- Temporary power supply
- Field support.
Installation of the Gorgon umbilical is planned to occur from late 2023 or early 2024 to mid-2024 and the total duration of activities is expected to be approximately six months.
The submission is currently being assessed by NOPSEMA.