Attachment C - SCG Soil test and Footing report

construction area. The exposed face should also be protected against the potential for stormwater erosion.
Should these recommendations be un-achievable the builder should seek guidance from this office on temporary
shoring, benching or other suitable techniques.

Areas where existing structures or trees are removed shall be backfilled with engineer approved fill material
compacted to achieve a minimum relative field density of 98% and be in accordance with AS2870-2011. Where
trees are removed prior to construction the moisture conditions of the soils must be allowed to normalise across
the site prior to commencing foundation preparations.

Any loose or soft material uncovered in the site preparation shall be removed and replaced with approved fill
material compacted in accordance with AS2870-2011, or alternative measures to be provided by the engineer.

We recommend using a footing system as per the attached plans and details on the prepared construction pad.

Site drainage during construction is important. Stormwater run-off should be diverted away from any foundation
excavations and not be able to pond within 5.0m of the building footprint. Temporary piping or spoon drains or
other practical methods should be used. Please refer to the Appendices to the rear of this report for drainage
management.

The final surface profile should fall away from any slab on ground for a minimum of 1.5m at a grade of no less
than 1 in 20. Refer to appendices for drainage recommendations.

Where site drainage and landscaping does not conform to the specifications of AS 2870-2011 and CSIRO
Information Service Sheet BTF-18 significant damage to the building can be expected. A single copy of this
document is issued with the original issue of this report. Please consult your builder or contact this office to obtain
a copy.

The builder must ensure the stability of neighbouring/existing structures is maintained through not
undermining their foundations. This is achieved via restricting any excavations to above a line radiating
downwards at an angle of 1 in 1.5 (vertical to horizontal) from the base of the foundation/structure to be
protected.

Any new vegetation including trees planted adjacent the structure should follow the recommendations appended
to this report.


6     FOOTING AND SLAB SPECIFICATIONS

Footing Details

All footings must be founded a minimum of 300mm into the NATURAL MEDIUM DENSE SILTY SAND (shown shaded
on the attached log sections). Dimensions and reinforcement requirements are detailed on the structural plans
and details.

Where the NATURAL MEDIUM DENSE SILTY SAND is deep or is covered by the introduction of or the presence of
existing fill, the footings are to be increased in depth to reach this level. Alternatively the footings can be
supported on piers founded into the foundation material or deeper as required to obtain the required strength.
Refer to the structural plans for details.

Where unexcavatable rock is encountered at depths shallower than the founding level, the strip footing (non-
retaining) depth may be reduced accordingly to a minimum of 150mm providing the footing is founded a minimum
of 100mm into un-weathered or un-disturbed rock. Additional reinforcement shall be provided in the footing at
the rock/soil interface. Please contact SCG Consulting Engineers to obtain an appropriate detail.

Drilled Piers Supporting the Footings

Where the NATURAL MEDIUM DENSE SILTY SAND is deep or to be covered by fill the footings can be supported on
drilled concrete filled piers founded at a minimum of 300mm into the NATURAL MEDIUM DENSE SILTY SAND. The
size and spacing of these piers is nominated on the structural plans.

Where drilling piers is not practical the footings could be supported on steel screw piers.

Where unexcavatable rock is encountered at depths shallower the founding level the piers shall be augered a
minimum of 100mm into un-weathered or un-disturbed rock.


      SCG Consulting Engineers                                3                                     SCG Ref: 30315(S)