ADG Dewatering Management Plan · OPW21/0315

                                                                                         ADG Consulting Pty Ltd


4    Water quality objectives
4.1 Receiving environment
     It is proposed to discharge extracted groundwater either to the local stormwater network on Wyuna
     Drive via a stormwater gully pit, or directly into the Noosa River adjacent to site. Based on the stormwater
     mapping available via the Noosa Council Enterprise Mapping System (Intramaps) there is a stormwater
     gully pit located approximately 40 m to the southeast of the site along Wyuna Drive. This stormwater pit
     terminates within the Noosa River (<40 m) directly east of the gully pit. The exact location of the receiving
     waters/environment will be confirmed on commencement of dewatering.

     The receiving environment in this location identifies as a moderately disturbed, middle estuary
     environment. The following section establishes water quality objectives (WQOs) to ensure that the
     environmental values of the receiving waters are protected and maintained.
4.2 Development of water quality objectives
     WQOs have been developed to support and protect the designated environmental values (EVs) for the
     receiving environment. The WQOs are based on a moderately disturbed level of protection for enclosed
     coastal/lower estuaries. The WQOs have been developed with reference to the following guideline
     documents:


          −    Australian and New Zealand Guidelines for Fresh and Marine Water Quality 2018. (ANZG 2018)
               The selected trigger values apply to moderately disturbed systems to provide a 95% level of
               species protection for marine waters.
          −    Environmental Protection (Water & Wetland Biodiversity) Policy 2019. 2019. Noosa River
               environmental values and water quality objectives. DES.
          −    Environmental Protection (Water) Policy 2009, Noosa River environmental values and water
               quality objectives. 2010. DERM.
          −    Queensland Water Quality Guidelines, Version 3, September 2009. 2013. DEHP.


     The Australian and New Zealand Guidelines for Fresh and Marine Water Quality by the Australian and
     New Zealand Environment and Conservation Council and Agriculture and Resource Management Council
     of Australia and New Zealand (ANZECC/ARMCANZ, 2000), has undergone review, with the publication of
     the 2018 version. The revised Australian and New Zealand Guidelines for Fresh and Marine Water Quality
     2018 is a joint initiative between the Australian and New Zealand Governments and Australian state and
     territory governments (ANZG, 2018) and supersedes the ANZECC/ARMCANZ 2000 publication. Where
     ANZECC/ARMCANZ (2000) is referenced, the relevant sections are still relevant and consistent with the
     updated ANZG 2018 publication, as referenced in the ANZG 2018 publication.

     The Queensland Water Quality Guidelines 2009 (DEHP, 2013) was made pursuant to the provisions of the
     Environmental Protection (Water) Policy 1999 (the EPP(Water)), which is a subordinate legislation under
     the Environmental Protection Act 1994 and was developed as the State response to the
     ANZECC/ARMCANZ (2000) Guidelines. The EPP(Water) provides a framework for:


          −    Identifying environmental values for Queensland waters, and deciding the water quality
               objectives to protect or enhance those environmental values.
          −    Including the identified environmental values and water quality objectives under Schedule 1 of
               the EPP (Water).
     WQOs are long term goals for surface water quality management. They are indicators established for
     receiving waters to support and protect the designated Environmental Values (EVs) for those waters.
     DERM (2010) describes that for slightly to moderately disturbed waters, the guideline values should be
     compared with the median of values at a test site, whilst ANZG (2018) stresses that the aquatic ecosystem


ADG1290.21 Dewatering Management Plan_Rev0_12.10.21                                                         Page 6