REFERENCE DOCUMENTS - RAL25/0004 (As Published)

        9.1.5.      GROUNDWATER
                    Groundwater was encountered underlying the site at relatively shallow depths with impacts correlated
                    with heavy metal soil concentrations. Groundwater results indicate that the site is a probable source of
                    elevated copper and zinc within groundwater, which has potential to impact sensitive off-site and
                    downgradient ecological receptors, with the nearest being surface channels and associated riparian
                    vegetation leading to Six Mile Creek some 1.3km to the north and south of the site, which discharges to
                    the Mary River some 35km to the north-west. The absence of a human health risk, and intervening land
                    uses and distance to the off-site ecological receptors, reduces the risks posed by the recorded
                    groundwater quality.
                    The observed elevated heavy metals within groundwater are unlikely to preclude the proposed
                    development, with the likely scope of remediation works to result in removal of the probable source being
                    fill and waste material and some secondary impact to underlying natural soils.

        9.1.6.      RISK EQUATION
                    As outlined in Section 2.1 for this assessment the Site Contamination Risk Equation (Risk Equation) is
                    used:

                                                                            Each variable can have the following values:
                                                                            1 = Exists
              Source x Pathway x Receptor = Risk                            0 = Does not exist
                                                                            If any of the variables have a value of 0 then the Risk is
                                                                            also 0 or low risk
                    The Risk Equation simply determines if a risk is present but not the magnitude of the risk (in terms of
                    consequence or likelihood). In practical terms it is not possible to assess source related hazards to a
                    level where they can be stated as being non-existent and some residual hazard that may result in a risk
                    may remain. Non-existent is intended to mean low risk.
                    The following sub-set of potential risk sources (AEC, refer to Table 8) were investigated in accordance
                    with the agreed scope and limitations, and their conditions at the completion of the investigation are
                    summarised below.
                    Table 21 Risk Equation Summary
                                                                                      Complete




                                                                                                                                             Resultant
                                                                                                                             Receptor
                                                                                      Pathway


                                                                                                  Pathway




                                   Potential Hazardous             Source
              AEC                                                                                           Receptors
                                   Contaminant Source6             Value
                                                                                                  Value




                                                                                                                             Value




                                                                                                                                             Risk




              1 – Northern         Variable wastes and             1             All             1          All human      1            Medium to High
              night soil           heavy metals detected                         pathways                   and
              and bottles          at concentrations                                                        ecological
              disposal             above ecological and
              area                 human health SAC (no
                                   biogas or LFG
                                   detected)




                    6
                        Note that with respect to Table 21 and in accordance with the agreed scope and limitations of the works, the potential hazardous
                         contaminant sources of landfill gas, PFAS, PAH, PCB and SVOC have not been quantitatively assessed to date.




        125 Lot 105 SP118458 Cooroy DSI 12062024 Rev0                                                                  Lot 105 SP118458, Cooroy, QLD, 4563
        12/06/2024                                                               76                                 Detailed Site Contamination Investigation
Document Set ID: 23717062
Version: 0, Version Date: 01/01/1900