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3 FIELDWORK METHODS
The fieldwork for the investigation was undertaken on 19 August 2024 and included the following:
•   Three (3) bores drilled and sampled in accessible locations to various depths utilising hand-held auger
    equipment; and
•   A dynamic cone penetrometer (DCP) test was undertaken at surface level at each bore.
A suitably experienced and qualified geotechnician was present during the fieldwork to carry out site
assessments, perform insitu testing and to log the encountered subsurface conditions through observation of
drilling and excavation techniques, returned cuttings, and anecdotal evidence provided by drilling staff.



4 FIELDWORK RESULTS
The subsurface conditions encountered in the bores are described in detail on the log sheets in Appendix C,
together with accompanying notes in Appendix A which define the classification methods and descriptive terms
used. The depths were measured below existing surface levels at the time of investigation.
The subsurface conditions encountered on site can be broadly categorised in Table 1.
TABLE 1: SUMMARY OF SUBSURFACE CONDITIONS

Material                             Information

SAND                                 The site can be characterised as comprising dune sand. The sand is very loose
                                     initially, grading medium dense below approximately 2 m depth. The medium dense
                                     sand is the target stratum for footings.



No groundwater seepage was encountered in the bores at the time of investigation; However, given the nature
of the subsurface conditions, it is paramount to give consideration to how groundwater levels can fluctuate
with time and are transient in nature and how they could be perched or how they could be introduced from
foreign sources (such as broken water infrastructure).



5 COMMENTS
5.1 EARTHWORKS COMMENTS
Prior to any construction at the site, any deleterious materials and vegetation, should be stripped from within
building envelopes.
During construction, some loosening of the surface sands in excavations is expected. Therefore, the base of
any excavation should be soaked and re-compacted using a vibratory plate compactor prior to constructing
any footings/slabs. Confirmation of adequate compaction of sands could be obtained by carrying out DCP
tests to achieve the above target value.
If filling is required, it is recommended that sand at this site and imported fill be placed in loose lift thickness of
not more than 200 mm, within 2% of optimum moisture content, and with each layer compacted to achieve not
less than 8 blows per 300 mm rod penetration to a depth of 1.0 m, when using a DCP.
Imported fill, if required, should comprise free draining cohesionless sand with less than 5% by weight of
particles passing a 0.075 mm sieve. The material should be free from organic matter and large particles.




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