Rehabilitation and decommissioning spotlight

Chevron Australia has retired and rehabilitated the Thevenard Island oil facility, with environmental outcomes that are industry-leading in the Pilbara. The project aims to maximise the circular economy and restoring the land to be compatible with the adjacent nature reserve and the island’s future tourism activities. 

Rehabilitated areas are now thriving, with a return of fauna including active nesting and use of the rehabilitation for refuge. Ongoing monitoring using novel remote sensing techniques will reduce future human impact on the area.

Production on the Campbell platform ceased a number of years ago. Following a period of careful planning the Santos team, in partnership with contractors, designed and executed a way to remove the Campbell platform in offshore WA in three sections. 

Following removal, 99.5 per cent of the recovered platform totalling 930 tonnes of material, was recycled through local WA facilities. 

Santos’ staged approached to decommissioning of assets improved safety, increased local supply chain capability and participation, and allowed for greater learning opportunities across the organisation.

Since the takeover of AWE Limited in 2018, Mistui E&P Australia acquired the Woodada gas field and actively started decommissioning. This has included plug and abandonment of wells, removal of infrastructure and facilities, and rehabilitation of the land. 

Rehabilitation activities including the plug and abandonment of the last seven wells is ongoing, and all sites will be fully reinstated by 2028. 

Rehabilitation is regularly monitored and measured against completion criteria set in consultation with DMPE and other regulatory agencies. Rehabilitation monitoring and management of the field will continue until completion criteria are reached and the area reflects the environmental values of the surrounding Lake Logue Nature Reserve which is recognised as a significant wetland for birds and threatened flora.

The North-East Box Cut landform at Rio Tinto Iron Ore’s Tom Price mine contained approximately 2.6 metric tonnes of potentially acid forming material (PAF), posing an environmental risk if not properly managed. 

Despite being constructed in the 1990s with limited PAF material controls, rehabilitation of the 72 hectare area was successfully completed in January 2022 through partnerships with Pilbara Aboriginal businesses. 

It was preceded by multiple years of planning, with detailed analysis of PAF behaviour informing the final landform and store-and-release cover designs. 

Over a 25-month project duration, more than three million cubic metres of material was moved into place to create the final landform. 

Learnings from this project have directly influenced progressive rehabilitation strategies at Rio Tinto mines, including mine plan integration, enabling more waste rock back-fill into mine pit voids to significantly reduce future waste landform requirements. 

This project demonstrates the value of integrating rehabilitation planning with operational waste management, even in legacy areas.