Attachment 6 - Odour Impact Assessment - Katestone · 132005.638.06

7. RESULTS

Table 7 presents the maximum modelled odour concentrations at any of the specific sensitive receptors (detailed
in Table 3) for the composting in isolation, and for the composting and landfill facilities combined, with the results
reflecting the landfill with both lower-bound and upper-bound emission rates. A contour plot of the proposed
composting operation’s modelled contribution in isolation is presented later in Plate 1, and in combination with the
landfill in Plate 2 (lower bound landfill emissions) and Plate 3 (upper bound landfill emissions).

The results demonstrate the following:

    •    The footprint of odour impacts from the composting operations in isolation is very small, with a maximum
         99.5th percentile 1-hour average odour concentration at a sensitive receptor of just 0.4 ou, and the contour
         in Plate 1 demonstrating that odour impacts will largely be confined within the facility boundary. Given
         how small the contribution of the landfill is to odour concentrations, it is obvious that the change of location
         of the green waste stockpile referred to as “Commercial drop”, as described in Table 1, is of no
         consequence in terms of potential odour impacts.

    •    When considered cumulatively with the lower bound landfill odour emissions, impacts remain small, with
         a maximum 99.5th percentile 1-hour average concentration of 1.4 ou. The contribution of the composting
         operation to cumulative concentrations is negligible.

    •    When considered cumulatively with the upper bound landfill odour emissions, the maximum 99.5th
         percentile 1-hour average concentration exceeds the odour guideline at three properties to the southwest
         of the facility. The contribution of the composting operation to these cumulative concentrations is
         negligible. These predictions likely over-state the probable impacts of the combined Noosa Resource
         Recovery Centre operations, but at the same time are consistent with there having been complaints
         associated with the landfill operations.

In simple terms, the results demonstrate that the composting facility will have a negligible odour impact, being
highly unlikely to lead to odour impacts at sensitive receptors. There will remain a potential for the landfill operations
to cause impacts, but consistent application of best practice management measures for controlling odours from
landfills (such as consistent and comprehensive application of day cover, and prompt installation of gas extraction
following filling of landfill cells) should be adequate to ensure that impacts are minimised, if not entirely prevented.
The proposed composting operation, provided it is well-managed, is highly unlikely to contribute meaningfully to
any odour impacts.




 Katestone Environmental Australia Pty Ltd                                                          17 September 2026
 D25072-8 Noosa Council - Noosa Composting Odour Assessment - Final                                          Page 18