Dewatering Management Plan

                                                                                        ADG Consulting Pty Ltd


     River canal) is to be confirmed, however it is anticipated to be directly east of the site. Background water
     quality monitoring of field parameters will also be conducted during each sampling event, if applicable.
     Background samples will be recovered from the river, either upstream or downstream from the receiving
     water location (tide dependant).

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

     Monitoring will be undertaken at the following frequencies:


          Daily monitoring of field parameters (pH & 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
           and dissolved 0.45µm filterable metals (aluminium, arsenic, cadmium, chromium, copper, iron, lead,
           nickel, zinc and mercury). Total aluminium and iron will also be analysed for, if required.
          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.
          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) and for soluble sulfate and chloride to assess changes
           in groundwater chemistry associated with PASS oxidation. Total aluminium and iron will also be
           analysed, if required.
          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.




ADG1786.25 Dewatering Management Plan_Rev0_20.02.25                                                       Page 14