June 2004, Ref. ME522
The introduction of the national environmental standards in 2004 will see heightened public awareness of air quality issues. Driven largely by a strong need for action on ambient levels of particles in most parts of the country, the standards lay the foundation for an effective air quality management framework. Atmospheric dispersion modelling is an essential tool in air quality management by providing the link between environmental effects and discharges to air. Its use has grown rapidly in New Zealand over the past 10 years and models are now commonplace in many resource consent applications for discharge permits.
This guide provides expert and well-debated guidance on dispersion modelling through a series of recommended protocols. To improve consistency and accuracy in modelling, the guide is reasonably prescriptive, but the recommendations are not regulatory requirements so there is flexibility to handle the wide variety of circumstances that occur in New Zealand.
Correct interpretation of modelling results against the national environmental standards and determination of the potential effects of a discharge are as important as accurate modelling results. This guide does not include guidance on interpreting results. Instead, this will be included in a Good Practice Guide for Assessing Discharges to Air (currently under development by the Ministry).