dewatering plan · OPW23/0189

                                                                                                ADG Consulting Pty Ltd


2        Site characteristics
2.1      Property description
         The site is described as Lot 149 on N21859, and is situated at 30 Mossman Court, Noosa Heads,
         Queensland. The site is understood to be currently occupied by a multistorey dwelling (Google
         Streetview, 28 September 2023) which is planned to be demolished. The site is irregular in shape and has
         an area of 610 m2. The site locality is shown in Figure 1, Appendix A.
2.2      Surrounding environment
         The surrounding environment and land use is described briefly in Table 1.

         Table 1 Surrounding land use and environment

                  Direction                                              Environment

                    North             Noosa River canal, then residential development

                     East             Residential development.

                    South             Mossman Court, then residential development, then Noosa River.

                    West              Residential development, then Noosa River.


2.3      Topography
         The site and surrounding land is considered to be generally level, with the site gently sloping towards the
         Noosa River canal from the south to north. Surface elevations range from 2.20 m to between 1.7 m AHD.
         Refer to Appendix C (Preliminary Concept Design ‐ Sections, 11/07/23).
2.4      Geology & soils
         The surface geology at the site is mapped as being Anthropocene aged gravel, sand and silt; man‐made
         deposits generally associated with land‐fill or mining (tailings, dumps and rehabilitated areas). The
         dominant rock type is identified as volcanic and metamorphic as reference through the detailed surface
         geology (accessed via Queensland Globe online, 28 September 2023).

         The Acid Sulfate Soils (ASS) mapping layer 1:100,000 Redcliffe to Teewah categorises the site as ‘SDL’ or
         ‘Acid Sulfate on Disturbed Land’, indicating that the site is likely to contain acid sulfate soils (and potential
         exists that partial or full treatment may have been undertaken), however limited field investigation has
         been performed in this area (accessed via Queensland Globe online, 28 September 2023).
2.5      Hydrogeology
         A search of groundwater bores licensed by DRDMW was conducted by ADG on 28 September 2023. The
         search identified no licensed bores within a 200 m radius of the site. A map showing the bore search area
         is provided in Appendix B.

         Based on the local geology and topography, and the site’s proximity to the Noosa River canal, the inferred
         groundwater flow is to the north. Groundwater beneath the site is likely to be hydraulically connected to
         the canal network and/or river, therefore saline groundwater conditions are anticipated, and additional
         saltwater intrusion is likely to occur during dewatering.




    ADG1580.23 Dewatering Management Plan_Rev0_28.09.23                                                             Page 3