6. Noosa River DMP Ver0 (Combined)

      DREDGING & NOURISHMENT- ENVIRONMENTAL ASPECTS, OBJECTIVES
      AND PLANNING ACTIONS
As dredging and disposal are occurring at the same time; with dredged material being placed directly onshore,
this section relates to management of both dredging and disposal activities.


            WATER QUALITY
The BMT Sediment Sampling Report (2022) indicates that the composition of sand source is shown to be
generally sand (93%), with minor fractions of clay / silt / gravel. Silts and clays have the potential to become
suspended in the water column and create turbid plumes. Tidal flows in this area of the Noosa River are expected
by be <0.5m/s. Tidal plumes are expected to be relatively small as the sediment is predominantly sand. The
dredging activity has been undertaken historically without water quality issues.
The nourishment activity is undertaken concurrently with dredging. The sand is expected to be generally
consistent in colour and grade with the beach that is nourishing. Nourishment area is above LAT and placement
will be on the visible beach above the water level with subsequent reprofiling as required. This will minimise
potential for sediment plumes.
Objective: To minimise impacts of dredging and disposal on water quality.
Issues: Releases of suspended sediment (i.e. turbidity) as part of the dredging activity and placement of
nourishment. Spill of hazardous substances (e.g. fuel or oil) during operations or refuelling.
Performance Criteria: All releases are within permit requirements. No spills or leaks of hazardous substances.
Control Measures:

                                                                                                                     Responsible
                                                   Control Measures
                                                                                                                        Party
 1.   Undertake the dredging activity in a manner that minimises the turbid plume as far as practicable.           Contractor
 2.   Implement dredging operational controls as required to ensure water quality requirements are met. This       Contractor
      may include control of production rates, timing of dredging activity to coincide with more suitable tides
      and/or other operational controls.
 3.   Fuel bunkering to be undertaken by a licenced contractor.                                                    Contractor
 4.   Oils and fuels to be securely stored within designated storage areas. Storage tanks to be either self-       Contractor
      bunded or bunded with impermeable surfaces and capacity to contain 110% of the largest tank storage
      capacity.
 5.   Undertake the dredging activity and ancillary activities in a manner that minimises the potential for oil,   Contractor
      grease, scum, litter or other visually objectionable matter to enter the waterways.
 6.   Oil spill management plan to be implemented. Management Plan to be located on board. Staff are to be         Contractor
      suitably trained. Suitable oil spill control stations to be located onboard.
 7.   Plant and equipment is to be clean of silt, pests and other contaminants. Plant to be well maintained.       Contractor


Monitoring: Monitoring is to be undertaken in accordance with Table 4.


18