Compiled Reference Document - MCU25/0020 (As Published)

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 0.45um 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 0.45um 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.

 

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