NSW EPA Launches Major Review of Air Pollution Modelling Methods

Summary

Active remediation systems in New South Wales face higher regulatory hurdles.

The NSW EPA has opened public consultation on an overhaul of the Approved Methods for the Modelling and Assessment of Air Pollutants. This statutory document dictates how emissions must be modelled for sites requiring an Environment Protection Licence under the POEO Act.

While these changes are often associated with heavy industry, they directly affect the contaminated land sector. If your remediation strategy involves soil vapour extraction, thermal desorption, groundwater air stripping, or landfill gas flaring, you will soon need more comprehensive baseline meteorological data.

Relying on old dispersion models under the new framework could lead to costly environmental impact statement rejections or stalled site approvals. Environmental consultants and site auditors should prepare to adopt modernised predictive tools.

Is your proposed remediation design relying on legacy air modelling techniques?

This is an Machete news summary. Full summary and source references are available below.

Further detail

The technical details of this review carry specific weight for practitioners designing active remediation systems.

The Approved Methods are a statutory requirement where an Environment Protection Licence or other statutory instrument references them, or where the EPA directs their use. They do not apply automatically to all licence holders, but they are the benchmark for assessing stationary source emissions.

The draft updates introduce several significant changes. Regulators are actively promoting the use of site-specific data over generic regional datasets to improve predictive accuracy. Health-based criteria are being updated alongside clearer triggers that dictate when additional mitigation is mandatory.

For consultants preparing an Environmental Impact Statement or a Remediation Action Plan, this means the baseline data collection phase must be detailed and site-specific. The review also introduces more prescriptive requirements for dust control and modernised methods for assessing odour in non-urban areas.

Failure to align with the NSW Clean Air Strategy and these updated methods will likely result in protracted approval times for complex remediation sites.

Background and context

Headline: NSW EPA Launches Major Review of Air Pollution Modelling Methods: Stricter Approvals Ahead for Active Remediation Systems

On 23 March 2026, the NSW Environment Protection Authority (EPA) opened public consultation on a major review of the Approved Methods for the Modelling and Assessment of Air Pollutants. This statutory document sets out the requirements for how air emissions from stationary sources must be modelled where an EPL or other statutory instrument references the Approved Methods, or where the EPA directs their use and assessed to inform regulatory decisions under the Protection of the Environment Operations Act 1997 (POEO Act).

The draft updates are designed to align the state’s modelling techniques with contemporary science, emerging technologies, and the NSW Clean Air Strategy. Key changes include promoting the use of on-site data to improve accuracy, modernising predictive pollution modelling tools, updating health-based criteria, and introducing clearer triggers for when extra mitigation is needed, more prescriptive requirements for dust control, and better ways to assess odour in non-urban areas.

NSW EPA Executive Director of Regulatory Practice and Services, Arminda Ryan, noted: "Air quality is fundamental to community health and the resilience of our environment, and our regulatory tools must reflect the most up to date science and contemporary practice… We now have an opportunity to modernise how we assess emissions from large industrial activities and address emerging issues, new technologies and evolving environmental risks."

Why it Matters for Environmental Professionals:

While this review is primarily framed around large industrial facilities, mines, and power stations, it carries direct, high-stakes implications for the contaminated land, remediation, and waste management sectors.

References and related sources

• Primary source: www.epa.nsw.gov.au
• ienvi.com.au
• https://www.epa.nsw.gov.au/
• NSW EPA

How iEnvi can help

iEnvi provides specialist consulting services relevant to this topic. Our team includes CEnvP Site Contamination Specialists with experience across contaminated land, groundwater, remediation, ecology, and regulatory compliance.

• iEnvi contaminated land services
• iEnvi remediation services
• iEnvi expert services and independent review services

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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: 26 Mar 2026

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