Gorgon; Source: Chevron

Go-ahead for Chevron to move forward with ops designed to sustain gas project’s production levels

Chevron Australia, a subsidiary of the U.S. oil and gas giant Chevron, has received a green light for its revised environment plan (EP) from Australia’s offshore regulator for activities created to help maintain the current production rates at its natural gas project off the northwest coast of Western Australia.

Gorgon; Source: Chevron

The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) recently accepted Chevron’s revised environment plan, proposing activities related to Gorgon’s gas development pipeline and subsea infrastructure installation and pre-commissioning operations within production licenses WA-39-L and WA-19-PL offshore Western Australia.

Chevron Australia operates the Gorgon project on behalf of the Gorgon joint venture. This project 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.

Since the goal is to keep the gas output from the project at a high level, the company plans to install a subsea compression station and associated infrastructure in the Jansz–Io gas fields to maintain the gas supply to the facility on Barrow Island and to sustain current gas production rates.

To this end, Chevron Australia intends to install subsea structures, including a compression station, compression manifold station, and associated foundations alongside a normally unattended, floating field control station anchored to the seabed by 12 mooring lines.

In addition, the operator plans to install an umbilical to supply power from Barrow Island to the field control station, and power cables, known as flying leads, from the field control station to the subsea compression station; an umbilical to transmit power and communications between the field control station and the existing Jansz CDU; and pipeline crossings and rock stabilization as required.

While the Jansz–Io gas fields are located within production licenses WA‐36‐L, WA‐39‐L, and WA‐40‐L, approximately 200 kilometers off the northwest coast of Western Australia in water depths of approximately 1,350 meters, the Jansz feed gas pipeline is licensed by WA-19-PL, which extends from the state/Commonwealth waters boundary to the northwest of Barrow Island, out to the Jansz–Io gas fields.

The scope of activities covered by Chevron’s EP entails installation; inspection, maintenance, and repairs; pre-commissioning; and field support. The installation is scheduled to occur from mid-2024 to mid-2026. The Gorgon gas field is located around 130 kilometers off the northwest coast of Western Australia and 65 kilometers northwest of Barrow Island in water depths of approximately 200 meters. The initial field development was commissioned in 2015, covering wells and subsea infrastructure, including the feed gas pipeline.

This led to the first LNG cargo departing Barrow Island in March 2016 while the domestic gas supply to the Western Australian market began in December 2016. Chevron describes the Gorgon project as one of the world’s largest natural gas projects and the largest single resource project in Australia’s history. This project exports liquefied natural gas to customers across the Asia Pacific and produces domestic gas for the Western Australian market.

The Gorgon field development was expanded by Gorgon stage 2 (GS2), which enriches the Gorgon and Jansz-Io gas fields with 11 additional wells and accompanying offshore production pipelines and subsea infrastructure to maintain future gas supply to the three existing LNG trains and the gas processing facilities on Barrow Island. 

Related Article

Recently, Tokyo Gas divested its minority interests in four LNG projects off the coast of Australia, including its stake in Gorgon, to EIG-managed MidOcean Energy. As a result, the Chevron-operated Gorgon project is a joint venture between the Australian subsidiaries of Chevron (47.3%), ExxonMobil (25%), Shell (25%), Osaka Gas (1.25%), MidOcean Energy (1%), and JERA (0.417%). 

Chevron is actively working on stepping up its oil and gas portfolio expansion as confirmed by recent deals in Namibia and Uruguay. Hess Corporation’s shareholders recently endorsed the firm’s proposed merger with Chevron despite an arbitration process with its partners in the assets located in the Stabroek block off the coast of Guyana.