Australian Government guidance for removal of oil and gas property and sea dumping of infrastructure in Commonwealth waters

Summary 

Decommissioning is a normal and necessary activity in the lifecycle of every offshore oil and gas project. It involves removing or otherwise satisfactorily dealing with property and infrastructure previously used for oil and gas operations. Decommissioning must be timely, safe and environmentally responsible.

Australian law requires the removal of all oil and gas property and infrastructure from the sea as part of decommissioning. This reflects Australia’s international obligations and aims to minimise risk to the marine environment or other marine users in the future. 

Australian law also prohibits sea disposal of material considered too harmful to be released into the marine environment. Australia regulates permitted sea disposal to minimise any potential environmental impacts.

In limited circumstances, alternative decommissioning approaches may propose leaving certain types of offshore oil and gas property and infrastructure in the sea. These may be considered if environmental impacts and risks are acceptable to regulators. In such circumstances the proposal needs to meet all applicable regulatory requirements.

Titleholders^[1] and operators of oil and gas projects in Commonwealth waters proposing an alternative to full removal requirements to leave certain types of property and infrastructure in the sea need to seek regulatory assessment by submitting:

• an environment plan under the Offshore Petroleum and Greenhouse Gas Storage Act 2006 (OPGGS Act)
• an application for a sea dumping permit under the Environment Protection (Sea Dumping) Act 1981 (Sea Dumping Act).

Titleholders will also need to submit a referral under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) for any decommissioning activities outside the title area that occur in state or territory waters, and where the proposed activities are likely to have a significant impact on a matter of national environmental significance under the EPBC Act. 

1. Purpose

This guidance clarifies the Australian Government’s regulatory requirements for removing oil and gas property and infrastructure from Commonwealth waters as part of decommissioning. It is expected that all property and infrastructure will be removed when oil and gas operations have ended. However, there may be limited circumstances where regulators may grant approval for certain property and infrastructure to be left in the sea.

The guidance details 2 categories of property and infrastructure:

• property and infrastructure that cannot be left in the sea
• property and infrastructure that may be assessed under the OPGGS Act and Sea Dumping Act to determine whether it may be left in the sea in limited circumstances.

This guidance is consistent with the Sea Dumping Act and OPGGS Act. It was developed by the:

• Department of Climate Change, Energy, the Environment and Water (DCCEEW)
• Department of Industry, Science and Resources (DISR)
• National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA).

1.1. Scope and limitations

This guidance does not replace, nor limit, the OPGGS Act and Sea Dumping Act and their associated regulations. This guidance should be read alongside relevant Australian Government guidance as referenced in this document.

This guidance is not advice on what ministers, or their delegates or agencies, will or will not approve. This guidance does not give advice on decisions taken by NOPSEMA, which makes regulatory decisions independent to the government. 

This guidance also does not give any advice on:

• legal requirements
• third-party liability exposure
• occupational health and safety
• marine engineering.

Titleholders should seek independent advice on these and any other issues.

1.2. Application of guidance

In this guidance, ‘property and infrastructure’ refers to oil and gas structures, infrastructure, equipment and property. When property and infrastructure is left in place, abandoned, dumped or toppled, it is referred to as ‘left in the sea’.

The guidance applies to all oil and gas property and infrastructure brought into an offshore title area granted under the OPGGS Act. 

Any property and infrastructure not included in this guidance still needs to be assessed where applicable under:

• the OPGGS Act
• Sea Dumping Act
• other relevant laws, such as the EPBC Act.

This guidance does not apply to property and infrastructure from other industries, or which is not used in the exploration for or recovery of oil and gas. It does not apply to re-using or repurposing oil and gas infrastructure. Titleholders are encouraged to engage with NOPSEMA and DCCEEW at an early stage when considering the potential re-use or repurposing of property and infrastructure.

This guidance applies to removing property and infrastructure from Commonwealth waters. Commonwealth waters are any area of water situated between 3 nautical miles from the territorial sea baseline and the outer limits of the Australian continental shelf. This guidance does not apply to activities in designated coastal waters or internal state waters.

This guidance does not cover any requirements or considerations outside the OPGGS Act and Sea Dumping Act. Titleholders must consider any other requirements not mentioned in this document.

2. Removing property and infrastructure

The OPGGS Act and associated regulations regulate decommissioning of offshore oil and gas property and infrastructure in Commonwealth waters. The safety risks of decommissioning activities are important for titleholders to consider when planning for removal of all property and considering any alternative approach. If a titleholder proposes an alternative to removal of all property and to leave certain types of property and infrastructure in the sea, they also need approvals under the Sea Dumping Act.

DISR and NOPSEMA administer the OPGGS Act. DISR is responsible for developing policy and regulations for oil and gas and greenhouse gas storage activities in Commonwealth waters. NOPSEMA is Australia's independent regulator for health and safety, structural (well) integrity and environmental management of offshore energy and greenhouse gas storage activities in Commonwealth waters. 

The Sea Dumping Act is administered by DCCEEW, which is responsible for:

• protecting Australia’s environment and water
• delivering the government’s climate change and energy agenda. 

The Sea Dumping Act protects the Australian marine environment by preventing or regulating the loading and dumping of waste and placement of artificial reefs in Australian waters^[2].

2.1. International memberships and legal obligations

Australia’s international memberships and legal obligations guide our regulation of decommissioning activities, especially the:

• 1996 Protocol to the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1972 (the London Protocol)
• United Nations Convention on the Law of the Sea (UNCLOS)
• International Maritime Organisation (IMO) Resolution A.672(16) adopted on 19 October 1989.

The London Protocol’s aims are to:

• protect and preserve the marine environment from all sources of pollution
• take effective measures to prevent, reduce, and eliminate pollution caused by dumping of wastes or other matter at sea.

Australia is a Contracting Party to the London Protocol. As part of Australia’s international obligations, it must uphold these aims and apply a precautionary approach to environmental protection from dumping of wastes and other matter. This includes activities associated with decommissioning offshore infrastructure. 

In 2019, the parties to the London Protocol issued the Revised specific guidance for assessment of platforms or other man-made structures at sea. The revised guidance gives more detail on assessment considerations for evaluating applications to leave oil and gas infrastructure in the sea. As a Contracting Party to the London Protocol, the Australian Government considers this guidance when assessing sea dumping applications. 

UNCLOS regulates all aspects of the resources and uses of the sea, including navigational rights, and conserving and managing living marine resources. Australia’s obligations as a party to UNCLOS include:

• establishing and maintaining navigational and safety aids for international vessels
• effectively protecting the marine environment.

IMO Resolution A.672.16 sets globally recognised principles for removing and disposing of offshore structures and installations. Australia is a member of the IMO and the government considers these principles when making decisions on decommissioning. These principles mean that there are types of property and infrastructure that cannot be left in the sea (as detailed in Table 2).

2.2. Offshore Petroleum and Greenhouse Gas Storage Act 2006

Titleholders are required to decommission and remove all property and infrastructure from a title area in accordance with section 572(3) of the OPGGS Act. This is consistent with Australian Government policy and our international obligations. It is an Australian Government policy principle that removal of all property is the default decommissioning requirement under the OPGGS Act. Property removal requirements are subject to any other provision of the OPGGS Act and regulations in accordance with section 572(7). For more information see the Australian Government’s Guideline: Offshore petroleum decommissioning.

Titleholders are encouraged to plan for decommissioning at the early stages of project development, as part of an overall field development strategy. For more information go to NOPSEMA’s Planning for proactive decommissioning information paper. Titleholders must plan and provide for removal of all property, unless and until alternative arrangements are approved by NOPSEMA. This includes ensuring there is an appropriate cost estimate and sufficient financial provisioning to address decommissioning costs. 

Titleholders must identify and manage the risks to safety when planning for decommissioning. A facility must have a registered operator and safety case in force until decommissioning activities are complete, under the Offshore Petroleum and Greenhouse Gas Storage (Safety) Regulations 2024. Safety cases may also be required for other facilities (such as vessels) involved in decommissioning works. These activities may proceed only once the safety case has been accepted by NOPSEMA. For more information see NOPSEMA’s document Section 572 maintenance and removal of property.

In limited circumstances, NOPSEMA may consider proposals to leave property and infrastructure in place, where the proposal demonstrates that the environmental impacts and risks will be reduced to as low as reasonably practicable, are of an acceptable level and are consistent with the principles of ecologically sustainable development. The principles of ecologically sustainable development are outlined in Section 3A of the EPBC Act. The proposal must meet safety and all other applicable requirements under the OPGGS Act and regulations, and other applicable laws. The proposal must also demonstrate that beneficial environmental outcomes can be achieved. Beneficial environmental outcomes may relate to:

• enhancing marine ecosystems (living and non-living resources) over the long term
• the conservation of habitats for the protection of biological diversity and ecological integrity
• the maintenance or enhancement of economic, social and cultural benefits to people and communities. 

In these cases, a titleholder may apply to NOPSEMA for approval to leave property and infrastructure in the sea which includes submission of an environment plan. NOPSEMA assesses all environment plans against criteria in the Offshore Petroleum and Greenhouse Gas Storage (Environment) Regulations 2023 (Environment Regulations). The Environment Regulations ensure offshore oil and gas activities are carried out in a way that is consistent with ecologically sustainable development. 

What NOPSEMA considers to be an ‘acceptable level’ will vary depending on the project and proposal. For more information see NOPSEMA’s Environment plan decision making guideline and Environment plan content requirement guidance note. More information on deviation from removal requirements is in the Australian Government’s Guideline: Offshore petroleum decommissioning.

Titleholders seeking approval of an alternative decommissioning approach to leave property and infrastructure in the sea must consider and address several factors. These factors are outlined under section 3 of this guidance: Considerations for property and infrastructure proposed to be left in the sea.

Titleholders must complete the removal of property before the surrender of title, in accordance with section 270(3)(c) of the OPGGS Act. For more information see NOPSEMA’s Section 270 Consent to surrender title policy. The OPGGS Act contains provisions ensuring the costs and liabilities that are associated with an oil and gas activity remain the responsibility of those who held the title, or had the ability to influence activities under the title. For more information see the Australian Government Guideline: Trailing liability for decommissioning of offshore petroleum property.

2.3. Environment Protection (Sea Dumping) Act 1981

The Sea Dumping Act protects Australia’s oceans from waste and pollution dumped at sea. It does this by preventing or regulating the dumping or abandonment of platforms and other man-made structures:

• in Australian waters
• from Australian vessels in any part of the sea. 

The abandonment, movement, or modification of structures or materials for disposal at sea associated with the offshore oil and gas industry requires a permit issued under the Sea Dumping Act and Environment Protection (Sea Dumping) Regulations 1983.

Oil and gas activities that may need a sea dumping permit include:

• moving oil and gas property or infrastructure from its location and dumping it in Australian waters
• abandoning in-situ oil and gas property or infrastructure in the location where it originally served its purpose in Australian waters
• placing an artificial reef in Australian waters that includes decommissioned oil and gas infrastructure. 

A permit application submitted under the Sea Dumping Act must demonstrate that any proposal to leave property or infrastructure in the sea:

• is environmentally acceptable
• not contrary to the aims of the London Protocol.

Sea dumping permit applications must be assessed against Annex 2 of the London Protocol^[3]. Annex 2 outlines the comprehensive Environmental Impact Assessment (EIA) requirements that the Sea Dumping Act requires. This allows DCCEEW to take a cautious and robust approach to permit assessments and recommendations to the minister or delegate. The EIA is informed by current and reputable scientific guidance that is internationally accepted. 

Considerations in Annex 2 include, but are not limited to:

• detailed description of the waste proposed to be left in the sea (including the chemical, physical, and biological properties)
• detailed description of the location where the waste is proposed to be left
• evaluation of waste reduction/prevention opportunities
• discussion of the potential impacts on human health, living resources, amenities, and uses of the sea (as identified through comprehensive consultation).

Visit the DCCEEW’s sea dumping page for more information. 

Operators do not need sea dumping permits for exploration, exploitation or offshore processing activities in Australian waters (including the sub-seabed). This includes well plugging and abandonment activities at the end of the operational phase.

The Minister for the Environment and Water, or their delegate, makes the final decision on whether to grant or refuse a sea dumping permit. This guidance document does not pre-empt any decision that may be made.

2.4. Environment Protection and Biodiversity Conservation Act 1999

The Environment Protection and Biodiversity Conservation Act 1999 (the EPBC Act) is the Australian Government’s main environmental legislation. It is a legal framework to protect and manage matters of national environmental significance, including threatened flora, fauna, ecological communities, heritage places and Commonwealth reserves (including Australian Marine Parks).

NOPSEMA's environment plan assessment and approval process is accredited under Part 10 of the EPBC Act (the Program). This strategic arrangement means classes of actions, if done following the above process, will not need separate referral, assessment, and approval under the EPBC Act. These actions include on title decommissioning activities in Commonwealth waters. An EPBC Act referral is required for activities outside the title area if they are not covered by the Program and likely to have a significant impact on a matter of national environmental significance under the EPBC Act. 

The Director of National Parks has issued class approvals that authorise offshore petroleum exploration, construction, production and decommissioning activities and greenhouse gas exploration activities to occur in certain marine park IUCN category VI zones. If the activity is occurring in an Australian Marine Park and is not covered by existing class approvals, a separate authorisation from the Director of National Parks is required. For more information see NOPSEMA and the Director of National Parks’ Petroleum activities and Australian Marine Parks guidance note. 

Titleholders must determine the technical and legal requirements for environmental approvals that may be required for off-title activities, including those relating to the EPBC Act.

3. Considerations for property and infrastructure proposed to be left in the sea

It is expected that all property and infrastructure will be removed when oil and gas operations have ended. However, there may be limited circumstances where regulators may consider proposals for certain property and infrastructure to be left in the sea. In such circumstances, the proposal must demonstrate that environmental impacts and risks will be reduced to as low as reasonably practicable, is of an acceptable level and is consistent with the principles of ecologically sustainable development. In addition, all applicable regulatory requirements, including those regarding safety, need to be met and the proposal must demonstrate that beneficial environmental outcomes can be achieved. Titleholders seeking to leave property and infrastructure in the sea need to demonstrate that the impacts and risks of this are:

• acceptable under the Sea Dumping Act and London Protocol
• acceptable and as low as reasonably practicable under the OPGGS Act and regulations.

In these cases, titleholders must address the below considerations as part of their environment plan submissions and sea dumping permit applications, having regard to specific requirements under the relevant legislation and the specific circumstances of their activity (see Table 1). Examples of specific assessment considerations for certain categories of property and infrastructure are also provided at Table 3. Table 3 provides examples of property and infrastructure that may be assessed under the OPGGS Act and Sea Dumping Act to determine whether it may be left in the sea in limited circumstances. Further considerations may also be required noting each project will be assessed case by case.

Notes: please read section 4 of this guidance along with the above considerations. It includes the:

• references to extra guidance material
• categories and types of property and infrastructure that may be assessed under the OPGGS Act and Sea Dumping Act to determine whether it may be left in the sea. 

The titleholder must address any scientific or technical uncertainty around the outcomes of leaving property and infrastructure in the sea. Titleholders should include how uncertainty will be characterised and addressed. The government will not consider a proposal to leave property and infrastructure in the sea until the titleholder addresses scientific and technical uncertainty.

3.1. Consultation

Offshore oil and gas titleholders must consult when preparing an environment plan and an application for a sea dumping permit. Under the Environment Regulations, titleholders must consult relevant authorities, persons and organisations (known collectively as relevant persons) when preparing an environment plan. This allows relevant persons to assess any impact the activity may have on their functions, interests or activities. For more information see NOPSEMA’s Consultation in the course of preparing an environment plan.

Applications for a sea dumping permit must include discussion of potential effects on human health, living resources, amenities, and other legitimate users of the sea. These effects may be identified and understood through consultation with people who have a connection to the sea.

Before applying for a sea dumping permit, applicants must undertake consultation with (including but not limited to):

• relevant advisory bodies and government authorities
• local stakeholders and First Nations peoples who the proposal may affect.

When considering decommissioning options, titleholders must consult relevant persons under the OPGGS Act and other marine users for the purposes of a sea dumping permit, whose functions, interests or activities may be affected by the activity. For the purposes of preparing an environment plan, titleholders must assess the merit of any objections and claims through the environmental approval process.

Titleholders must also consider the impacts that leaving property and infrastructure in the sea may have on relevant persons and stakeholders in the future.

4. Categories of property and infrastructure

4.1. Category 1: Property and infrastructure that cannot be left in the sea 

4.2. Category 2: Examples of property and infrastructure that may be assessed under the OPGGS Act and Sea Dumping Act to determine whether it may be left in the sea 

More information

NOPSEMA guidance

• NOPSEMA - Decommissioning
• NOPSEMA - N-00500-PL1903 A720369 Section 572 maintenance and removal of property
• NOPSEMA - N-04750-GL2086 A900179 Consultation in the course of preparing an environmental plan guideline
• NOPSEMA - N-04750-GL1721 A524696 Environment Plan decision making guideline
• NOPSEMA - N-04750-GN1344 A339814 Environment Plan content requirement guidance note.

International conventions and guidance

• 1996 Protocol to the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter 1972 (the London Protocol)
• 2019 Revised specific guidance for platforms or other man-made structures at sea (LC 41/17/Add.1, Annex 8)
• IMO Resolution A.672(16) - Guidelines and standards for the removal of offshore installations and structures on the continental shelf and in the Exclusive Economic Zone
• United Nations Convention on the Law of the Sea of 10 December 1982
• United Nations Environment Programme Global Mercury Partnership Study report: mercury from oil and gas
• Adopted technical guidelines issued under the Basel Convention.