Chevron Australia has completed onshore decommissioning works at Thevenard Island in Western Australia.

The decommissioning process involved the plugging of 11 onshore production wells, three water disposal wells, one exploration well and the safe dismantling and removal of three 150,000-barrel oil storage tanks in addition to production tanks, separator vessels, flowlines, associated process infrastructure and ancillary accommodation facilities and utilities including the controlled toppling of the 38-metre communications tower. In total, the project resulted in the removal of more than 5,000 tonnes of scrap metal from the island for recycling.

The project was logistically complex given the remote nature of the island, and technically challenging given Thevenard Island is a nature reserve and the area is adjacent to a tourism operator.

The rehabilitation process also included the planting of more than 120,000 native seeds. Monitoring of the rehabilitation will be carried out over the next few years.

First explored in the late 1960s, Thevenard Island has been home to the Chevron-operated Thevenard Island Joint Venture oil and gas facility located around 22 kilometres from Onslow. The facility commenced producing oil in 1989, with approximately 150 million barrels of oil produced over its 25-year life until production ceased in 2014.

The area will be returned to the WA Government once it is restored to a condition similar and compatible with the adjacent environment.

Decommissioning of the Chevron Australia-operated Barrow Island Joint Venture (BWIJV) oil facility and associated infrastructure on Barrow Island, is expected to commence in 2025.

Chevron Australia’s Director of Operations Danny Woodall said decommissioning is a growing industry that provides economic opportunities as assets enter the later stages of their lifecycles.

“Decommissioning is an enormous economic opportunity that will grow as existing assets enter the later stages of their lifecycles,” Mr Woodall said.

Chevron Australia’s Thevenard Island Retirement Project Manager Chris Jones said the project highlighted Chevron’s commitment to responsible late life asset management as well as the opportunity decommissioning can provide to deliver positive outcomes for the environment and local community.

“The Thevenard Island Retirement Project is an example of Chevron’s commitment to progressing decommissioning and rehabilitation activities in a systematic and timely manner to deliver positive outcomes for the environment and local community,” Mr Jones said.