RFI - Attachment D - Geotechnical Investigation Report · MCU25/0053

                                                                                                           PTG/01608 – 0001 – Rev0

Table 1: Summary of Materials Encountered in Boreholes

              Borehole No.                          Non-soil - Pavers (m)                    Fill - Silty Sand (m)

                   BH1                                         -                                   0.0 – 4.5
                   BH2                                     0.0 – 0.1                                  0.1 – 4.5
                   BH3                                     0.0 – 0.1                                  0.1 – 4.5
                   BH4                                     0.0 – 0.1                                  0.1 - 4.5

DCP testing undertaken indicated that sands generally have a medium dense to dense relative density, with some
loose material encountered near the surface.

Groundwater was not encountered during the drilling of the boreholes. It should be noted that groundwater levels can
be perched and fluctuate seasonally and during and after heavy rainfall events. Given this natural variability, it is
prudent to assume that water levels can fluctuate. Furthermore, the site is in close proximity to the tidal Noosa River
and the materials encountered are of a permeable nature, which increases the likelihood of groundwater levels
fluctuating.



7 LABORATORY TESTING AND RESULTS
Laboratory testing was undertaken by a Nationally Association of Testing Authorities (NATA) accredited laboratory
on soil samples taken at every 0.25 m depth in accordance with the ‘National Acid Sulfate Soils Guidance: National acid
sulfate soils sampling and identification methods manual’ (Department of Agriculture and Water Resources, 2018). This
document is herein referred to as the ‘National Acid Sulfate Soil Guidelines’.

Initial laboratory testing included field pH (pHF) and field pH peroxide (pHFOX) tests in order to arrive at a ‘positive field
sulphide identification’ and to inform the selection of samples for further testing. A summary of the results is presented
below in Table 2. The samples highlighted in Table 2 were selected for further testing. Laboratory reports of test
results are attached in Appendix 3.

Table 2: Field pH (pHF) and Field pH Peroxide (pHFOX) Screening Results
                                                              pHF             pHFOX          Reactivity           pH Difference
    Borehole        Sample Depth         Material
                                                           (pH units)       (pH units)        Number               (pH units)
                         0.25             SAND                4.9              2.6                2                    2.3
                         0.50             SAND                4.9              2.0                3                   2.9
                         0.75             SAND                5.0              2.8                2                   2.2
                         1.00             SAND                4.9              2.4                2                   2.5
                         1.25             SAND                5.2              2.7                2                   2.5
                         1.50             SAND                5.8              2.4                2                   3.4
                         1.75             SAND                6.2              2.7                2                   3.5
                         2.00             SAND                6.0              2.7                2                   3.3
                         2.25             SAND                6.1              2.6                2                   3.5
       BH1
                         2.50             SAND                5.5              2.3                2                   3.2
                         2.75             SAND                5.8              1.9                3                   3.9
                         3.00             SAND                5.8              2.0                2                   3.8
                         3.25             SAND                6.0              1.5                2                   4.5
                         3.50             SAND                6.4              2.2                4                   4.2
                         3.75             SAND                5.9              2.2                4                   3.7
                         4.00             SAND                5.8              1.7                2                   4.1
                         4.25             SAND                5.7              1.7                2                   4.0
                         4.50             SAND                6.1              2.2                4                   3.9
                         0.25             SAND                6.3              3.9                2                   2.4
                         0.50             SAND                6.4              3.8                2                   2.6
      BH2
                         0.75             SAND                5.9              3.8                2                   2.1
                         1.00             SAND                6.1              3.5                2                   2.6
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