Western Australia establishes regulatory framework for greenhouse gas storage and aquifer protection

Overview

Western Australia commenced two new sets of greenhouse gas storage regulations on 30 June 2026, establishing the state’s first comprehensive statutory framework for onshore and coastal carbon capture and storage (CCS) projects. The Petroleum and Greenhouse Gas Storage (Submerged Lands) (Greenhouse Gas Injection and Storage) Regulations 2026 (WA) and the Petroleum, Geothermal Energy and Greenhouse Gas Storage (Greenhouse Gas Injection and Storage) Regulations 2026 (WA), together referred to here as the GHG Regulations, were introduced under the Petroleum Legislation Amendment Act 2024 (WA). They sit within the broader legislative architecture of the Petroleum, Geothermal Energy and Greenhouse Gas Storage Act 1967 (WA) and the Petroleum and Greenhouse Gas Storage (Submerged Lands) Act 1982 (WA). The dual-regulation structure reflects the jurisdictional split between onshore and submerged-land operations within three nautical miles of the Western Australian coast.

For environmental professionals, the commencement of these regulations is a materially significant event. Until now, proponents pursuing CCS projects in Western Australia operated in a regulatory environment that lacked clear state-level guidance on storage formation declarations, site planning obligations, aquifer protection standards, and site closure criteria. The GHG Regulations fill that gap with prescriptive technical requirements that will directly shape the scope and cost of hydrogeological investigations, subsurface modelling programmes, and long-term monitoring obligations. Project developers, industrial emitters seeking to offset operational emissions, and landholders over prospective storage formations all now face a structured and demanding approval pathway that did not previously exist in this level of detail at the state level.

The timing is also relevant. Australia’s national CCS ambitions have grown considerably in the context of net-zero commitments, with projects such as the Gorgon CCS facility on Barrow Island and various emerging industrial decarbonisation proposals highlighting both the potential and the technical complexity of large-scale geological storage. Western Australia’s regulatory move provides a state-level framework that complements the existing offshore Commonwealth regime and signals that the state government is preparing its regulatory infrastructure for a pipeline of CCS project applications.

Key details of the Western Australia GHG Storage Regulations 2026

The GHG Regulations are structured around two principal schedules that address distinct stages of the project lifecycle. Schedule 1 sets out the requirements governing the Minister’s power to declare a geological formation as an “identified GHG storage formation.” This declaration is a prerequisite to obtaining an injection licence, and the criteria for declaration are technically demanding. Proponents must demonstrate, through detailed geoscientific evidence, that the target formation is capable of safely containing injected greenhouse gases over the long term. This includes proof of structural integrity, adequate injectivity, and the absence of migration pathways that could allow gas to escape the designated formation boundary. The formation must also sit wholly within an existing petroleum lease or permit area, which has implications for tenement strategy and how proponents structure their land access arrangements prior to any injection application.

Schedule 2 governs the preparation and content of site plans, which are comprehensive technical documents that must describe and govern all injection and storage operations. The site plan requirements go well beyond a project description. They must include predictive modelling of gas migration behaviour within the subsurface, geochemical assessments of host rock and porewater interactions with injected CO2, and clearly defined operational envelopes including maximum injection pressures and volumes. Critically, approved site plans are subject to mandatory periodic review at least once every five years. In addition to that scheduled review cycle, specific regulatory triggers can require an immediate plan review. While the source material does not enumerate each trigger exhaustively, the framework signals that regulators will be able to require updated assessments in response to unexpected monitoring results, changes in formation behaviour, or modifications to injection operations.

The aquifer protection provisions within the GHG Regulations represent one of the most technically significant elements for hydrogeologists and environmental scientists. Operations must be conducted in a manner that reduces the risk of aquifer contamination, particularly in formations situated outside the declared storage zone. This is not a generalised duty of care. The regulations impose explicit obligations to prevent gas migration into non-target formations, which means proponents must define the spatial extent of the storage complex, identify all overlying and adjacent aquifer units, and establish baseline groundwater quality conditions before injection commences. Continuous monitoring throughout the operational life of the project will be required to demonstrate ongoing compliance with these protection obligations.

The site closure process introduces the concept of trailing liability management as a formal regulatory obligation. Before a site can be closed and a licence surrendered, operators must produce monitoring data sufficient to demonstrate that the stored greenhouse gas is behaving predictably and that containment integrity is being maintained. This requirement has direct implications for the duration and cost of post-injection monitoring programmes, which in the international CCS literature are frequently designed to extend for decades beyond the cessation of active injection. Proponents should therefore account for long-term monitoring costs and data obligations when assessing project feasibility well before any injection licence application is lodged.

References and related sources

• Primary source: www.claytonutz.com
• legislation.wa.gov.au
• allens.com.au
• claytonutz.com
• claytonutz.com

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This is an iEnvi Machete news summary. Prepared by iEnvi to summarise the source article for contaminated land, groundwater, remediation, approvals and site risk professionals.

Published: 05 Jul 2026

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