3. Noosa Project Restoration Plan V12

                                                           and further distorts any potential
                                                           natural character of the substrate.

                                                           Placing shell in cages, which
                                                           decompose by rusting over time, may
                                                           allow time for oyster shells to cement
                                                           together by natural biogenic
                                                           processes, prior to the supporting
                                                           cage structure disappearing. However,
                                                           this design is yet to be fully tested and
                                                           is possibly best suited for sub-tidal
                                                           environments where the biogenic
                                                           structures are not subject to high
                                                           current and wave energy, which may
                                                           cause movement or erosion of the
                                                           biogenic reef structures.

                                                           Not augmenting the restoration
                                                           substrate with oyster shell and seeded
                                                           oyster cultch and live oysters risks
                                                           slow ecological recovery, or possibly
                                                           low recruitment due to the variable
                                                           nature of oyster recruitment.
Substrate     Substrates are designed to maximise          Alternative configurations could
design        stability, durability, rugosity,             include larger substrate footprints of
engineering   heterogeneity, prevent impediment to         continuous rock, but such structures
              fish passage, avoid pooling, minimise        would likely affect river flow, may
              wave refraction, and erosion of              create barriers to fish passage,
              shorelines.                                  enhance the erosion potential and
                                                           sediment accretion potential of the
                                                           substrates to the adjacent shoreline
                                                           and shoreline upstream and
                                                           downstream of the restoration site.

Works         The construction contractor will be          The work methods are standard
methods       responsible for all works, from material     practice which are refined for each
              storage and load out to construction,        estuary situation. Work methods are
              construction monitoring, risk                adaptively refined, if required, but the
              management and reporting.                    conservation of existing habitats is
                                                           paramount to the methods.
              The contractor will operate in accordance
              with the specifications in this plan, Site   The use of larger deployment
              Establishment and Management Plan and        equipment, deployment of smaller
              Construction and Environmental               amounts of substrate but this is
              Management Plan (CEMP) and all relevant      neither economically efficient nor
              permit conditions.                           enables the project to meet minimum
                                                           restoration targets in an effective
              Substrate deployment is timed to coincide    timeframe.
              with periods of the highest natural oyster


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