Offshore carbon capture and sequestration

The Environment Protection (Sea Dumping) Act 1981 (Sea Dumping Act) regulates the disposal of carbon dioxide (CO2) by carbon capture and sequestration (CCS) at sea.

What is offshore CCS

Offshore CCS can potentially reduce emissions from hard-to-abate industrial sectors. CO2 is separated from other gases during industrial processes and compressed. A suitable CO2 stream may then be stored in sub-seabed geological formations.

Sea dumping permits

You need a sea dumping permit if you want to dispose of CO₂ by CCS in Australian waters.

The Minister (or delegate) must be satisfied that the material meets the criteria to grant a sea dumping permit.

Criteria are listed in the 1996 Protocol to the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1972 (the London Protocol). This includes the composition of a CO₂ stream and any contaminants.

Permits ensure that:

CO₂ streams are loaded, transported, and sequestered at appropriate offshore sites
we manage the risk of negative impacts to the marine environment and human health.

When you apply for a sea dumping permit, you will need to propose, and justify, its duration. Timeframes must be sufficient to undertake the long-term monitoring that must occur during and after the disposal of the CO₂.

Other legal requirements

Offshore greenhouse gas (GHG) storage in Australian waters is also regulated under:

the Offshore Petroleum and Greenhouse Gas Storage Act 2006
relevant state or territory laws.

You may also need to refer your project under Australia’s national environment law, the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).

You should engage with all relevant regulators early and keep doing so. Discussions will cover consistency, timing and your regulatory obligations. We are happy to participate in joint meetings with other regulators to discuss your activity.

The Australian Government has produced high-level guidance on Offshore Carbon Capture and Storage Regulatory Approvals. This will help you navigate permitting and approvals in Commonwealth waters.

More information on regulating offshore GHG storage and regulatory responsibilities in Commonwealth waters is available through:

CCS activities that may need a sea dumping permit

For permit applications under the Sea Dumping Act, the Environment Minister will consider:

the specific circumstances of the project
whether the sequestration of CO₂ in Australian waters constitutes sea dumping (under the London Protocol and the Sea Dumping Act).

Depending on the proposed activity, you may require:

more than one permit
multiple permits, if additional sources of CO₂ are added later.

Scenarios

These scenarios can help determine if an intended offshore CCS activity requires a sea dumping permit. This diagram applies only to activities in Australian waters.

Scenario one

CO₂ captured onshore is processed. It is then loaded, transported, and sequestered in an offshore greenhouse gas title (Title A).

Scenario 2

CO₂is captured from an offshore petroleum title (Title B). It is then brought back onshore for storage and/or processing. Then it is loaded, transported and sequestered in an offshore greenhouse gas title (Title C).

Scenario 3

CO₂ captured from an offshore petroleum title (Title D). It is processed, loaded and transported directly to a different offshore title for sequestration (Title E).

Note: The Offshore Petroleum and Greenhouse Gas Storage Act 2006 (OPGGS Act) and associated regulations provides for the exploration and exploitation of petroleum and greenhouse gas (GHG) in Commonwealth waters.

The OPGGS Act also establishes a title system for the assessment, injection, and storage of GHG. This is administered by the National Offshore Petroleum Titles Administrator. An offshore GHG title grants the titleholder the right to explore, appraise, inject and store CO₂. An offshore petroleum title grants the title holder the right to explore and produce oil and or gas.

More information about sea dumping in Australian waters is available at Sea dumping.

If you need help to decide whether your offshore CCS activity needs a sea dumping permit, email seadumping@dcceew.gov.au.

Offshore CCS National Action List

A National Action List is required to meet our obligations under the London Protocol.

We are working with the Commonwealth Scientific and Industrial Research Organisation to develop it. This will allow us to regulate offshore CCS projects in Australia effectively.

The list:

is a screening tool to assess suitability for the disposal of CO2 into sub-seabed geological formations
outlines acceptable incidental associated substances and upper levels
helps assess any potential effects on the marine environment and human health.

Read Interim National Action List for offshore carbon dioxide sequestration.

Application form

Our offshore CCS permit application form incorporates feedback received during consultation. The form is consistent with Australia’s international obligations under the London Protocol.

It reflects criteria from:

Download

Permit application form for dumping of carbon dioxide streams by carbon capture sequestration at sea (PDF 390 KB)

Permit application form for dumping of carbon dioxide streams by carbon capture sequestration at sea (DOCX 106 KB)

If you need help accessing these files, visit web accessibility.

Application assessment and timeframes

The department assesses your application against the requirements of the Sea Dumping Act and the London Protocol. Read more at Assessing your application.

You should consider the schedule for your construction and injection during project planning. Injection of CO₂ cannot proceed until a permit is granted.

Waste management

Your application must include a discussion of other appropriate ways to reuse, recycle, or treat the waste. The London Protocol requires that environmentally preferable alternatives are favoured over sea dumping.

First consider reducing greenhouse gas emissions in ways other than injecting CO₂ into the sub-seabed. You must provide information on this in your application. More information is in paragraphs 3.3 and 3.4 of the 2012 Specific Guidelines for the Assessment of Carbon Dioxide for Disposal into Sub-Seabed Geological Formations.

Injection plans

Your injection plans must be robust. The design and construction of the injection well must be considered. This includes:

cementing
long-term integrity
peak pressure
volume
temperature.

If you are planning to use an existing or abandoned well, its history is also important.

Section 5.2 of the application form provides further information on injection plan requirements.

Information regarding CO₂well integrity is in the 2006 Risk assessment and management framework for CO₂ sequestration in sub-seabed geological structures. This includes information on:

site selection
site characterisation
potential operational releases
exposure.

More information can be found in sections 1, 3 and Appendix 1 of the Risk assessment and management framework.

Overwhelmingly consisting of CO₂

CO₂streams may only be considered for dumping if they consist overwhelmingly of CO₂ (Annex 1, paragraph 4, London Protocol). They may contain other substances derived from the source material and the capture and sequestration processes.

ISO 27914:2019 (Carbon dioxide capture, transportation, and geological storage) outlines the accepted interpretation of a CO₂stream. That is, ‘it is overwhelmingly consisting of CO₂'. This is defined as containing a concentration of CO₂ greater than 95% per mol %.

Permit conditions

If you are granted a sea dumping permit, you become a permit holder. Your permit will include conditions, for example:

provide the exact coordinates of the offshore CO₂ injection sites
specifications and standards for wellbore construction
the types of CO₂ stream monitoring and loading equipment (used to verify CO₂ stream composition and monitor injection rates, plume migration, leakages, and subsidence)
ongoing monitoring and management of the offshore CO₂ project, including the submission of periodic reports to the department or other specified agencies
requirements for the plug and abandonment of the injection well
the removal of the project’s infrastructure when the permit expires.

The permit holder must comply with the conditions of the permit.

Where appropriate, we aim to align sea dumping permit conditions with EPBC Act approval conditions. High-level guidance can assist you to manage regulatory requirements and timings for your offshore CCS project.

Adding a new CO₂stream to an existing permit

We are aware that offshore CCS projects can be delivered through a variety of business models. These could include a hub and/or cluster network model. CO2 streams may share transportation infrastructure in these models.

We are currently investigating available mechanisms for how the Sea Dumping Act may facilitate different types of offshore CCS projects.

Varying a granted permit

A permit holder may apply to the Minister (or delegate) to vary the operation of a permit.

Varying an existing permit is at the discretion of the Minister.

An example of an acceptable permit variation could be a minor change, such as a small increase in time for the granted permit.

You cannot vary a sea dumping permit to change the permit holder’s details or transfer a granted permit to a new permit holder.

Export of CO₂ for offshore sequestration and offshore sequestration of imported CO₂

Australia accepted the 2009 amendment to the London Protocol and declared it’s provisional application on November 7, 2024. This allows CO₂ to be exported for offshore disposal outside of Australia. It will also allow imported CO₂ to be sequestered offshore Australia.

For both scenarios, we must see evidence of an agreement or arrangement with the other country before we accept a sea dumping application. This is required to satisfy Australia’s obligations under the London Protocol.

In both cases, contact the sea dumping section at seadumping@dcceew.gov.au to discuss your CCS project.

Learn more about sea dumping and the London Protocol in Australia.

Contact us

Email: seadumping@dcceew.gov.au