Decommissioning

Decommissioning involves addressing infrastructure that is no longer required in a timely, safe and environmentally responsible manner.

IMPORTANT TOPIC

Decommissioning involves addressing infrastructure that is no longer required in a timely, safe and environmentally responsible manner

This can include full removal of structure or other alternatives.

Our approach¹

Woodside is committed to executing our decommissioning responsibilities safely, while also ensuring we have a focus on efficiency and lower cost. Decommissioning is integrated into project planning, from the early stages of development through to the end-of-field-life. This includes conducting comprehensive assessments to inform our planning and decision making, which is underpinned by science and marine research. In the developing regulatory environment, we continue to listen, learn and respond to our stakeholders, while expanding our global decommissioning experience.

Our decommissioning approach recognises the importance of reusing and recycling material from our decommissioning activities. We expect our contractors to apply Woodside’s waste mitigation hierarchy to maximise recycling efforts. This process prioritises reduction, reuse, recycling, and treatment over disposal. Our approach to decommissioning considers efficiencies relevant to all offshore decommissioning activities and onshore disposal. Woodside’s decommissioning estimate and restoration provision is calculated in accordance with relevant accounting standards. Our balance sheet is audited annually as part of financial reporting.

This section refers to current intentions, plans or stated targets (where applicable). It also outlines information regarding our Management System and relevant processes and procedures. Where we refer to our activities without reference to a previous calendar year or using present tense, the relevant content may be updated from time to time at our discretion but no reliance should be placed by the reader on this page being up-to-date. We also recommend checking our Announcements page regarding our most recent business activities.

Our performance¹

Woodside executed decommissioning work in 2023, spending approximately US$447 million in the year across our portfolio. Woodside is executing several decommissioning projects and is on track to meet our plans and any regulatory requirements. We continue to work with relevant regulators in each country to progress our decommissioning commitments.

The Enfield project, located approximately 38 km north of the North West Cape, Western Australia, ceased production in November 2018. All 18 Enfield wells have been plugged and 16 of the 18 xmas trees have now been removed. The remaining two trees are expected to be recovered in the first half of 2024 along with execution of the wellhead severance program.

In May 2023, Woodside completed award of all major contracts for the decommissioning of subsea infrastructure at the Enfield, Griffin, Stybarrow and Echo Yodel oil and gas fields offshore Western Australia. Finalisation of these contracts supported commencement of a decommissioning campaign in Q4 2023, although delays to regulatory approvals impacted some planned activities. The campaign will include the Griffin Riser Turret Mooring (RTM) and the Stybarrow Disconnectable Turret Mooring.

Woodside is partnering with a range of providers with specialist capabilities and experience to promote safe and successful execution of one of the largest decommissioning campaigns undertaken offshore Western Australia. We are progressing with our planning and remain on track to meet the regulatory requirements to complete the campaign. Woodside has undertaken extensive stakeholder consultation to inform the development of environment plans for the campaign. A number of these plans have been accepted with the regulator, NOPSEMA. The contracts have been awarded to a range of experienced and highly specialised service providers. They cover the removal and disposal of riser and disconnectable turret moorings, umbilicals, flowlines and other subsea infrastructure.

In October 2023, the Nganhurra RTM was safely and successfully removed from its location off the North West Cape in Western Australia and transported to the Australian Marine Complex (AMC) near Perth, to be cleaned and deconstructed in preparation for recycling and reuse.

The drill rig contract to complete the plugging of ten Stybarrow wells, was awarded in May 2023. This activity is planned to commence in Q1 2024 with all regulatory approvals in place.

The drill rig contract to complete the Minerva well plugging in the Otway Basin, South East Australia, has been awarded with execution planned for 2025. Contract awards related to the removal and disposal of the Minerva subsea infrastructure and pipelines in Commonwealth and Victorian State Waters are planned for early 2024.

Throughout 2023 the Bass Strait decommissioning project continued, with 111 wells permanently plugged. In 2023, the Gippsland Basin Joint Venture (GBJV) awarded contracts for a semi-submersible well intervention unit and a jack-up rig to commence plug and abandonment work in 2024. The GBJV has made progress in awarding a contract to a heavy lift contractor to execute decommissioning for several facilities in the Gippsland Basin.

In Canada, we are supporting the Operator’s decommissioning activities on Kitimat. Upstream included six well abandonments in Horn River, Sump remediation and water well site reclamation in Liard. Downstream included foreshore trestle removal, asbestos abatement and a Preliminary Detailed Site Investigation and Gap Assessment to inform revised site decommissioning plan (expected in 2024).

Waste management is a key requirement in our decommissioning contracts and we are working with our service providers to maximise re-use and recycling of our decommissioned infrastructure. Our current decommissioning projects in execution are on track to deliver in excess of 95% reuse/recycle of materials. Additionally, we are also exploring innovative solutions and technologies to further improve waste management practices, reduce environmental impact and identify ways to participate in a circular economy.

This section refers to our performance within a specific time period. Please note that the relevant year, where the activity applies, is stated where appropriate. Where we refer to our activities without reference to a previous calendar year or using present tense, the relevant content may be updated from time to time at our discretion but no reliance should be placed by the reader on this page being up-to-date. We also recommend checking our Announcements page regarding our most recent business activities.

Featured case study

Nganhurra RTM planning, execution and recycling

In October 2023, the Nganhurra Riser Turret Mooring (RTM) was safely and successfully removed from its location off the North West Cape in Western Australia and transported to the Australian Marine Complex (AMC) near Perth, to be cleaned and deconstructed in preparation for recycling and reuse.

View case study

Planning

Planning for decommissioning starts well in advance of asset end of life to pursue positive environmental, regulatory and social outcomes for the communities we operate in.

Within the next five years, Woodside will commence decommissioning planning for the Angel gas platform (based in the North West Shelf, Western Australia), the Ngujima-Yin facilities (offshore Exmouth, Western Australia) and has commenced planning for the Greater Angostura oil and gas assets in Trinidad and Tobago.

Woodside continues to develop processes to embed sustainable decommissioning principles at a project’s development phase, including early analysis of options, and regulatory and community engagement for growth projects. Woodside recognises that decommissioning is an integral part of project planning and should be assessed holistically to support project decisions.

We engaged with stakeholders, including the joint venture partner and regulatory agencies, early in the conceptual phase of the Trion project in Mexico, to develop a decommissioning strategy that considers the risks and benefits associated with various decommissioning options for the development. As part of this activity and to support the Field Development Plan (FDP), environmental studies and assessments were conducted to compare the potential impacts across multiple decommissioning options considering health and safety, the environment, technology, society, and associated costs. The identified decommissioning option was included in the FDP that has been approved by Comision Nacional de Hidrocarburos (CNH). As the Trion project progresses, Woodside remains committed to confirming decommissioning outcomes that continue to be well-understood and are aligned with local regulatory requirements and industry best practices.

Net Environmental Benefit Analysis (NEBA) studies are an important tool in decommissioning planning, specifically focused on environmental benefit analysis of the different options for retiring or removing production facilities. In coming years, input studies for NEBA assessments are expected to commence for Sangomar and the North West Shelf trunkline facilities. The trunkline studies will include a focus on habitat retention by establishing a baseline of the marine life environment to inform the decommissioning strategy.

Research and technology

Science and technology have an integral part to play in achieving positive environmental, regulatory and socio-economic outcomes from decommissioning.

Woodside is a founding member of Australia’s National Decommissioning Research Initiative (NDRI). NDRI is a collaborative industry fund that undertakes independent environment research to support the future assessment on the benefits, risks and impacts of different decommissioning options for offshore oil and gas infrastructure. NDRI is in Phase 2 of its research program, which commenced in 2023 and is planned to run through to 2026. Phase 2 will focus on improving the understanding of the marine environment around existing infrastructure.

Throughout 2024 Woodside plans to commence studies in the following areas to inform our decommissioning activities:

Technology advancement in well plug and abandonment execution
Plastics separation and disposal pathway management
Pipeline removal execution methods
Environmental impacts of pipeline removal
Chemical deposition assessments.

Woodside sponsors several research and development programs which aim to improve health, safety and environment outcomes and other aspects of decommissioning activities. Since 2021, we have committed more than US$1.9 million to support more than 20 additional projects with our research partners at Curtin University, Monash University, the University of Melbourne, and the University of Western Australia. These projects consider environmental monitoring, circular economy, and novel technology development for decommissioning operations. The research intends to help build local capability and capacity, thereby supporting better environmental, social and economic outcomes for the communities in which Woodside operates.

Collaboration

Safe and sustainable decommissioning of oil and gas assets will require a collaborative effort across industry and governments.

Woodside is an active member of the International Association of Oil & Gas Producers (IOGP) decommissioning working groups. As part of the IOGP, Woodside has access to subject matter experts, research data, and best practice guidelines – all of which are imperative for sustainably decommissioning our assets. Through IOGP Woodside is also contributing to the development of sustainable solutions for key themes within the global decommissioning landscape.

Woodside continues to support the Australian Department of Industry, Science and Resources’ enhancement of the decommissioning regulatory framework. In 2023, Woodside provided input into industry papers and actively participated in industry forums focused on decommissioning. In 2023, the Australian Federal government sought to understand the industry challenges and opportunities to develop a Decommissioning Roadmap, Woodside provided key insights directly and through Australian Energy Producers (AEP).

We continue to advocate in the jurisdictions where we operate for the importance of an approach to decommissioning that includes a holistic assessment of options and is risk based.

Industry wide collaboration will be required to manage the challenges from other industries for competing resources and equipment. For example, heavy lift vessels are required for both the removal of offshore oil and gas infrastructure as well as the installation of renewable energy infrastructure such as offshore wind turbines.