Judgment - Stockwell v Noosa Council - PEC Appeal 1998 of 2024 - 26.06.25 · MCU22/0094

6.4.3.7 MUSIC Results

The resulting percentage-based load reductions at the outlet are shown in Table 5 below together with
the Water Quality Objectives for the receiving waters.
                                                         Sources               Residual Load                 % Reduction                   Target %
Total Suspended Solids (kg/yr)                               601                       120                          80.0                        80
Total Phosporous (kg/yr)                                     1.51                     0.453                         70.1                        60
Total Nitrogen (kg/yr)                                      12.4                       4.76                         61.7                        45
Gross Pollutants (kg/yr)                                    84.8                       3.36                         96.0                        90
                                        Table 5 – Percentage Based Load Reduction Results

6.4.3.8 POD Pollutant Reduction

6.4.3.8.1 Litter

Rubbish bins will be located within the on-site bin store, for use by staff and visitors. The carparks will be
cleaned regularly. As a result of this and with the installation of the treatment devices, levels of litter
exiting the site via stormwater are expected to be negligible.

6.4.3.8.2 Sediment

The TSS outflow is identified in Table 5 above. As can be seen from the above table, the pollutant load
reduction achieves the Water Quality Objectives. The TSS level is therefore considered acceptable.

6.4.3.8.3 Nitrogen and Phosphorous

The TN and TP loads are identified in the Table 5. As can be seen, the TN and TP loads leaving the site
achieve the Water Quality Objectives. The Nitrogen and Phosphorous residual loads are therefore
considered acceptable.

6.4.3.8.4 Hydrocarbons

Hydrocarbons will become trapped within the bioretention filter media and the Jellyfish filters.

When there is a build-up of hydrocarbons within the bioretention basin, the top layer of the filter media
can be removed and replaced ensuring that no hydrocarbons are discharged from the site.

Studies have shown that micro-organisms in the organic mulch layer degrade and break down the
petroleum-based hydrocarbons and hence they will not be discharged from site.

When there is a build-up of hydrocarbons within the OceanProtect Jellyfish filters, the oils can be
vacuumed as per the maintenance procedures, to ensuring that no hydrocarbons are discharged from
site.




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Inspired engineering

10 April 2025
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