Appendix H Geotechnical Investigation - 14-16 Mary Street, Noosaville - Bounce Hostels 15.6.2018

J000605-001-R-Rev1                                                                                        March 2018


Previous experience and available guidelines indicate that ASS are normally restricted in extent to recent
(Holocene to Pleistocene age) soil horizons deposited in a saline environment below RL 5 m AHD. The
State Planning Policy, July 2014 (SPP14) applies to land, soil and sediment at or below 5 m AHD where the
natural ground level is less than 20 m AHD. Within such areas the SPP14 applies to development involving
any of the following:

       Excavating or otherwise removing 100 m³ or more of soil or sediment; or

       Filling of land involving 500 m³ or more of material with an average depth of 0.5 m or greater.
The topography of the site is consistent with the above criteria (i.e. majority of the surface elevation below
RL 5 m AHD) and the proposed development involves excavations that would exceed the above trigger
levels. SPP14 is therefore applicable to the proposed development and an assessment of potential
disturbance of ASS is required.
Details and results of the ASS assessment are provided in Appendix B, along with laboratory test
certificates. The outcome of the ASS assessment is summarised in Section 7.2.

7.2             Conclusion
The results from this investigation indicate that potential ASS (PASS) was encountered in the natural sands.
A lime treatment rate of 20 kg CaCO3/m³ is recommended, based on the results of the laboratory testing.
Given the anticipated volume of soils that will be disturbed and required lime treatment, management of
existing and potential acidity at this site would be classified as XH (extremely high) treatment in accordance
with Queensland Soil Management Guidelines V4.0 - Table 4.2 (i.e. greater than 25 tonnes of aglime).
The SPP14 guidelines require that for Category XH treatment, a stand-alone ASS Management Plan
(ASSMP) must be provided. Recommendations on strategies to be included in the ASSMP are as follows:

        Excavated soil must be managed by neutralisation of potential and existing acidity. Good quality
         agricultural lime should be thoroughly mixed with the spoil. Any lime treatment should be carried out
         in accordance with Queensland Acid Sulfate Soil Technical Manual, Soil Management Guidelines
         (Ver. 4.0. 2014).

        Treatment should be carried out on prepared pads. The earthworks strategy should be formulated to
         provide an appropriate sized pad to enable practical spreading, mixing and drying, so that adequate
         time is available to complete the treatment and verification before placing the next layer of soil. Should
         an area not be available for a treatment pad due to space restrictions treatment could be carried out
         in-situ.

        Stormwater should be diverted away from treatment/fill areas.

        Verification sampling and analysis is to be carried out on the treated soil to confirm that appropriate
         amounts of the neutralising agent have been incorporated into the soil.

        Groundwater quality should be monitored through new groundwater monitoring wells located across
         the site.

        Management of groundwater seepage and rainfall collected in excavations and other works areas on
         site, including treatment recommendations, must be incorporated into the ASSMP.

        During construction, it is recommended that all waters collected from groundwater or surface water
         inflow, be retained, monitored and if needed, treated to comply with the appropriate discharge criteria
         prior to discharge offsite.

8.0        LIMITATIONS
We draw your attention to the document, Limitations, which is included in Appendix B.
Should you require any further information please contact the undersigned.




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