Attachment 6 - Odour Impact Assessment - Katestone · 132005.638.06

A. While some sources at the composting facility (such as the maturation bays) will be covered to prevent ingress
of rainfall, all sources have been modelled as open area sources.


4.5       Presentation of results

Dispersion modelling results are presented for the composting facility in isolation, and in combination with existing
odour sources at the site (the landfill).

Odour emissions from the composting operation can be expected to be very different in character to those of the
landfill operations, being more earthy/woody/compost as compared to the sweet/rotten/pungent/sulphurous odours
commonly generated by landfill operations. Such different odours do not tend to have a cumulative effect in terms
of the odours from the different activities combining to make a stronger or more offensive odours; odours simply
do not tend to combine or interact in such a way. However, to provide a conservative estimate of the impact of
odour emissions due to the Noosa Resource Recovery Centre as a whole, this report presents odour from the
landfill and composting operations cumulatively.


4.6       Limitations and uncertainty

This study relies on the accuracy of a number of data sets that feed into the dispersion model, all of which will have
uncertainties associated with them. The input data sets include:

      •   Operational information for the Noosa Resource Recovery Centre provided by Noosa Council

      •   Emissions data derived from literature

      •   Meteorological monitoring observations from the Bureau of Meteorology

      •   Synoptic and surface information datasets from CSIRO.

It is also important to note that numerical models are based on an approximation of governing equations and will
inherently be associated with some degree of uncertainty. The more complex the physical model, the greater the
number of physical processes that must be included. There will be physical processes that are not explicitly
accounted for in the model and, in general, these approximations tend to lead to an over prediction of air pollutant
levels.

The dispersion model has been configured with conservative assumptions and, therefore, the assessment is likely
to overpredict the potential impacts of the proposed composting operations.




 Katestone Environmental Australia Pty Ltd                                                       17 September 2026
 D25072-8 Noosa Council - Noosa Composting Odour Assessment - Final                                       Page 12