Appendix G - Dewatering Management Plan · MCU25/0053.01

                                                                                        ADG Consulting Pty Ltd

      extracted groundwater, treated discharge water and off‐site monitoring in the receiving waters (in the
      mixing zone within a 20 m radius of the discharge point). The exact location within the receiving waterway
      (Noosa River) is to be confirmed. Background water quality monitoring of field parameters will also be
      conducted during each sampling event, if applicable. Background samples will be recovered from the
      Noosa River, either upstream or downstream from the receiving water location (tide dependant)
      approximately 300 m upstream of the discharge point).

      The proposed monitoring locations are shown in Figure 1, Appendix A and are subject to confirmation
      following mobilisation of dewatering equipment to site.

      Monitoring will be undertaken at the following frequencies:
         Daily monitoring of field parameters (pH, and turbidity) in the treated discharge water. Daily
          monitoring will be undertaken by a suitably trained site employee under the supervision of the Site
          Manager.

           Weekly monitoring of field parameters (pH, electrical conductivity, dissolved oxygen, temperature
            and turbidity) in the treated discharge water, receiving waters and background waters by ADG
            Consulting.

           Weekly laboratory analysis of treated discharge water and receiving waters for suspended solids,
            dissolved 0.45µm filterable metals (aluminium, arsenic, cadmium, chromium, copper, iron, lead,
            nickel, zinc and mercury) and total metals (aluminium & iron) by ADG Consulting.

           Pre‐discharge/initial monitoring of field parameters (pH, electrical conductivity, dissolved oxygen
            and oxidation‐reduction potential) in the extracted groundwater (prior to treatment) to assess
            changes in groundwater chemistry associated with PASS oxidation (sampled by ADG Consulting).

           Pre‐discharge/initial laboratory analysis of extracted groundwater (prior to treatment) for
            suspended solids, dissolved 0.45µm filterable metals (aluminium, arsenic, cadmium, chromium,
            copper, iron, lead, nickel, zinc and mercury), total metals (aluminium and iron) and for soluble
            sulfate and chloride to assess changes in groundwater chemistry associated with potential acid
            sulfate soil (PASS) oxidation (sampled by Environmental Consultant).

           Laboratory analysis of untreated groundwater would also be performed periodically (monthly) if
            changes in untreated groundwater pH levels are detected that may indicate local acidification, and
            to determine any changes in local groundwaters that may require further investigation of potential
            environmental impacts.

      All samples will be recovered by a suitably qualified Environmental Scientist and submitted to a National
      Association of Testing Authorities (NATA) accredited laboratory for analysis.
6.5.3 Monitoring responsibilities
      The persons responsible for undertaking the compliance monitoring described in Section 6.5.2 above are
      shown in Table 5.




 ADG1777.25 Dewatering Management Plan_Rev0_01.05.25                                                     Page 15