Reference Document - Geotechnical Investigation Report MCU25/0053 & OPW25/0074

                                                                                                                PTG/01608 – 0001 – Rev0


            Acidity/Equivalent Acidity value that exceeded the criteria was 26 mol H+/t (near the top of BH1), and the highest
            was 128 mol H+/t (near the base of BH3).

            The pHfield, pHFOX and confirmatory CRS results indicate the presence of Acid Sulfate Soils (Possible Acid Sulfate
            Soils) at the site within soils up to 4.5 mBGL (maximum investigation depth). Therefore, based on the test results, an
            Acid Sulfate Soil Management Plan (ASSMP) will be required if this project in to proceed.



            9 GEOTECHNICAL COMMENTS
            The geotechnical comments in this report are based on factual information collected during the fieldwork, best
            practice, local experience and published literature however are fundamentally opinion.

            In summary, the ground conditions that are likely to be encountered at the site can be characterised as comprising a
            surficial layer of topsoil, then silty sand/sand. Localised uncontrolled fill zones could also be encountered.


                      SITE CLASSIFICATION AND SITE MOVEMENTS
            In accordance with AS2870, the site is classified as class ‘A’ due to the ground conditions being sand with little or no
            ground movement from moisture changes to be expected.


                       FOUNDATIONS
            Based on an interpretation of the typical structural loads anticipated, and subsurface conditions encountered during
            the investigation, both high level and piled foundations could be considered suitable for the development.

            Based on the information available at the time of writing this report, general design parameters and recommendations
            have been provided in the subsections below which can be used for design of the foundation system of the structure.
            The design of the structure must consider the structural loads against serviceability.

            All footing excavations should be inspected by PTG to confirm that bearing pressures have been achieved, and
            footings are clean and free from loose and/or water softened materials.


                      9.2.1 HIGH LEVEL FOUNDATIONS
            Preliminary design of high-level pad footings up to 3 m wide or strip footings with a minimum 0.5m depth can be
            designed using the allowable bearing pressures in Table 2. Elastic settlements of properly designed and constructed
            high level footings are usually in the order of 10 mm for 0.5 m wide strip footings to 25 mm for large square pad
            footings up to 3 m wide.

            Table 6: Allowable Bearing Pressures for High Level Footings
                                       Material Type                               Allowable Bearing Pressure (kPa)
                                 Loose sand/silty sand                                     Not Recommended
                            Medium dense sand/silty sand                                            100
                                 Dense sand/silty sand                                              150

            Note that in sands, bearing capacity increases with depth. If foundation depths for the basement are provided, then
            updated parameters can be provided.


                      9.2.2 PILED FOUNDATIONS
            Bored or driven piles can be designed using the ultimate skin friction and base bearing capacities in Table 7 below.




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Document Set ID: 24149758
Version: 1, Version Date: 26/09/2025