Response to Information Request - Received on 19/04/2012 · OPW11/0335

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        8.0         SEDIMENT AND EROSION CONTROL PLAN


        The     Noosa       River: Environmental                      Values     and          Water      Quality Objectives       state        that the
        environmental values associated with the Noosa River Wetlands include aquatic ecosystem
        protection, and cultural and spiritual values. Because Noosa National Park is a protected area,
        these values require a high level of protection (level 1 protection).


        However the wetland adjacent to Noosa National Park is a disturbed ecosystem, as indicated
        by measured water quality parameters (Table 4-1). The existing caravan park development
        appears to be placing pressures on this wetland. The treatment train built for the proposed
        Essence of Peregian development is designed to improve the quality of water entering the
        wetland, and therefore, the water quality of the wetland. The target water quality objectives of
        stormwater entering the wetland are listed in Table 3-1.


        During the construction of the Essence of Peregian development, there is a hazard that
        disturbed soil might be carried into the wetland     by stormwater. In particular, fine sediment
        mobilised by stormwater will potentially carry nutrients into the wetland. The likely consequence
        of this is increased nutrient availability to weeds, with potential negative consequences for the
        adjacent Noosa National Park ecosystem.

        Assessment of the Queensland Best Practice Environmental Management Guidelines (DERM,
        2009) checklist (Table 8-1), shows that overall there is a high erosion hazard for this site. This
        hazard is directly affected by soil type (particularly imported,’fiII on lower slopes), the need to
        reshape the ground surface to install structwes, and the anticipated duration of site disturbance
        being 3 to 6 months. The hazard is greater during the wet season between November and July
        when the average monthly rainfall is expected to be above 100 mm.
                                                                                   .,




        Table 81 Factors Cont’b  mg t0 Eroslon. Hazard
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                                                   Erosion Hazard Assessment Form

         Controlling Factor                                                                         Points"                       Score
                                                                           ..
                                                                                                                     .;
         Average Slope of Whole Site                         ~: .,
                                                                     ;k~; i’~           ~’l’"’~;J     11f’!:1       -/               1
                                                                                             ~
                                                                          .~
         Soil type being disturbed                         ,~ ~’
                                                                                         ~..
                                                                                                    20r’5                         30r6

         Anticipated duration of site disturbance                                                     5                          8 or 11

          Erosive rainfall risk during site disturbance                            1 between Aug                -

                                                                                                                    Oct;
                                                                                                                              9 or up to 13
                                                                                    2 between Nov               -
                                                                                                                    Jul.

         Off-site sediment control (downslope of soil
                                                                                                      0                       9 or up to 13
         disturbance)
         Run-off entering the site                                                                    0                       9 or up to 13

         Extent of site disturbance                                                                   2                      11 or up to 15

         Total Score                                                                                11-15                  High Erosion Risk

        By implementing sediment and erosion controls, it is possible to moderate the erosion hazard.
        This includes protective covering of disturbed soils (particularly on erosion prone parts of the
        landscape, and when rain is expected), scheduling work to avoid the highest rainfall risk period,
        installing upslope diversion of runoff away from soil disturbance, and installing purpose built
        sediment control traps down-slope of the soil disturbance.


        The SECP has identified construction site best practices for managing sediment erosion and
        control. A daily site check-list will be used to ensure that building contractors are cognizant of
        and performing the required management actions.                                          This check-list is attached in Appendix C.




        @2012 Simmonds & Bristow Pty LId                                Contrast Constructions                             J-1005-31 0   -
                                                                                                                                             22 March 2012
        1:ICLlENTFILESIContrast Constructionsl11 08-155c   .
                                                            Essence of Peregian SCEP Stage 1 Updatel09_Output Documentsl11 08.155C SWM P _




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