Local Scale Dispersion Modelling to Support ACARP Emission Factors

There remains significant concern in the industry regarding the accuracy of air emissions estimation calculations / emissions inventories that are ultimately used to inform government air quality policy.

In particular, the potential for overestimation of mining related particulate matter (PM) emissions that may in turn result in unwarranted political and regulatory attention. There is also concern in relation to how the accuracy of the emissions estimation is related to predicted concentrations.

Previous project C26024 explored the reliability of the Australia-specific PM emission factors by completing a modelling assessment for individual mines, such as they would typically be applied in an impact assessment. Typical mine impact assessments employ emission factors referenced within the National Pollutant Inventory Emission Estimation Technique Manual for Mining (“the AP-42 emission factors”). The performance of the Australia-specific emission factors may then be compared with that of the AP-42 emission factors without the influence of other confounding factors.

Model outputs can also be compared with real world measurements from mine / NSW Department of Planning, Industry and the Environment (DPIE) PM10 monitoring stations at and beyond the site boundary to accurately evaluate performance.

The objective of this project was to further explore the reliability of the ACARP emissions factors by completing a modelling assessment for single mines, such as they would typically be applied in an impact assessment. This objective is to be explored by:

• Completing site-specific dispersion modelling to compare the use of US EPA AP-42 and Australia
• specific PM10 emission factors (“the AP-42 emission factors” and “the Australia-specific emission factors” respectively), control factors and other relevant information that are available.
• Provide a robust demonstration that the PM emission factors developed through previous ACARP funding can be used to improve atmospheric dispersion modelling performance against actual observations.
• Provide further evidence that the PM emission factors are applicable to the Australian mining industry, and should be adopted as industry-standard.