RFI - Attachment 4A - Response by Native Foresters

          o    Introduction of nutrients and propagules of invasive plant species into typically nutrient
               poor soils, leading to an increase in invasive plant species which will need to be
               managed through active and ongoing weed control operations.

  •       Moderate impacts for RE12.3.13 as detailed below:
          o Increased/intermittent surface water/ stormwater inputs to the north of the works
             impact area and the closed heathland / wetland Land Zone 3 ecosystems that occur
             there, are likely to lead to:
              ▪ Changes in water quality north of the works impact area (i.e. increase in pH,
                 increase in nutrient concentrations);
              ▪ Changes to soil chemistry (i.e. altering soil pH levels to a less acidic state);
              ▪ Changes in vegetation community structure favouring denser understorey of
                 sedges and ferns.
          o Intensification and further spread of existing weed outbreaks which will need to be
             managed through active and ongoing weed control operations.
                     .
The following impacts and potential impacts to native fauna from landfill expansion works have
been identified:

Groundwater Level Changes Impacts - Fauna:

      •    Excavation for the infrastructure may potentially breach/fracture any indurated material
           underlying areas of shallow ‘perched’ groundwater, reducing surface expression of
           perched groundwater. This could be detrimental to Swamp Crayfish and/or Wallum Froglet
           inhabiting these areas.
      •    Areas that receive inputs from the groundwater drainage management system may
           become wetter over time, with resulting changes in species composition and vegetation
           structure. Grasses and dry sclerophyll species may be replaced by sedges and wet-
           sclerophyll species. This may improve the habitat value of these areas for amphibians,
           although whether Wallum Frog species will be favoured will depend on the quality/pH of
           the groundwater.

Surface water Changes Impacts - Fauna:

      •  Changes to vegetation community composition and structure associated with increased
         surface water flows may affect the amenity or suitability of the habitat for breeding, foraging
         and dispersal by native fauna:
              o Localised waterlogging around HES Basin outlets and proliferation of water-
                 dependent native flora species (e.g. Melaleuca, sedges and ferns) will enhance the
                 amenity and suitability of these areas for amphibians and crayfish, however Wallum
                 Frog competitor species are likely to be favoured by the higher pH typical of surface
                 runoff.
        o The spread of weed species forming dense infestations (e.g. Para grass, Setaria
             grass, and Singapore daisy) around stormwater outlets is likely to intensify which will
             need to be managed through active and ongoing weed control operations.
      • Changes to soil chemistry and water quality associated with increased surface water flows
         may potentially alter the suitability of the heathland / wetland habitats for breeding by acid-
         specialist Wallum frogs, where the mixing of surface flows with groundwater has a diluting
         effect, resulting in higher pH.
      • Potential deleterious effects of nitrogen enrichment on amphibians and amphibian larvae
         if elevated concentrations (>10mg/L nitrate-nitrogen) are released, including:
              o Lethal effects (e.g. increased larval mortality); and
 Noosa Landfill & RRC – Response to RFI – Environmental Items (Dec 2023)                          Page|9