Attachment I - Updated Engineering Report & SWMP

                                Table 6.3.3 Treatment Train Effectiveness

                                      Flow          TSS          TP          TN         Gross
                                      ML/y          Kg/y        Kg/y         Kg/y      Pollutant
                                                                                         Kg/y
              Source Load              3.41          421         1.09         11.0        72.9
              Residual Load            2.18          82.9       0.266         3.45        2.38
              % Reduction              35.9          80.3        75.5         68.6        96.7
              %Target                    -            80          60           45          90
              Reduction

                   Please note that stochastic generation of pollutant loads has been
                   enabled so model results will vary slightly between runs.
                   Refer to Appendix C for MUSIC modelling files.

                   6.3.4 Maintenance

                   A recommended maintenance schedule for elements of the water
                   quality treatment train is outlined in Table 6.3.4.



                   Table 6.3.4: Treatment Train Maintenance Schedule

                                                            Minimum
  Device         Task            Labour           Plant     Frequency    Maximu          Failure
                                                               per          m             Mode
                                                             Annum       Frequenc
                                                                             y
Bioretentio    Inspection   Maintenance staff                   12           -            Grass
  n Area                         1 man          Whipper                                  exceeds
                                                Snipper                                 250mm in
                            Maintenance staff   Mower                                     height.
                Mowing           1 man                          12           As         Ponding in
                                                                          required     excess of 24
                            Maintenance staff   Shovel &                                   hrs.
                                 2 men           Truck                                Accumulatio
                Cleaning                                         4                    n of sediment
                                                                             As          or gross
                                                                          required      pollutants.




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    A6035/21/Engineering Report/30-32 Doonella Street, Tewantin                  Page 8 of 9
    May 2021    WM/tk
                                        Alta Projects P/L