soil test

3     SITE DESCRIPTION

The construction area has a gradient in the order of 12-20%.

Vegetation on the construction area (and nearby surrounds) consists of grasses and dense trees.

The existing surface drainage is good and sub-surface drainage is good.


4     FINDINGS

The soil profiles encountered are shown on the attached borelog sections.

No water table was encountered during our testing program.

The sandy soils encountered are susceptible to collapse when unconfined. This may effect excavations and
result in additional earthworks and increased concrete volumes. Temporary shoring or Forma-Tube may be
required to retain the sands prior to concreting.

The samples classified on-site were assessed as having negligible plasticity, therefore laboratory testing was
considered unnecessary.

We have assessed the expected differential movement of the soil profiles encountered to be the equivalent
of a site with a Ys of less than 20mm.

The following foundation material will provide a safe bearing capacity (100 kPa) for buildings within the scope
of AS 2870-2011 and is shown shaded on the attached logs;

         FOUNDATION MATERIAL - NATURAL MEDIUM DENSE SILTY SANDS

5     SITE PREPARATION DETAILS

We recommend scraping this site free of all organic material, topsoil and debris so that the proposed
construction area is levelled (within acceptable limits).

We recommend the structure be supported on steel screw piers designed and installed by a specialist
contractor to achieve the loads nominated on the structural plans.

We recommend scraping this site free of all organic material and debris. The site may then be cut and filled
to form level pads (as required). The fill should be clean material from the cut, laid out in 150mm (maximum)
layers and tracked rolled with the excavator (six passes in each direction). These earthworks must
incorporate surface spoon drains at the base and on the high side of the cut. Both drains must have an
efficient outflow downslope and clear of the dwelling. Cut batters of 1 to 2 (vertical to horizontal) and fill
batters of 1 to 3 will be stable providing all fill is compacted as above and exposed banks are protected
against erosion.

For the basement construction it is anticipated that battering is not likely to be suitable, bulk excavation will
therefore require positive support such as contiguous concrete piling. The design and certification of
temporary retention walls should be specifically designed and installed by a specialist Contractor and should
consider the protection of all neighbouring structures from movement and vibration damage. It is strongly
recommended a delapidation report of all neighbouring structures is undertaken prior to works commencing.

Where a retaining wall is required, a cut batter of 1 to 2 (vertical to horizontal) in the sand profile taken from
the base of the proposed wall should be excavated. These earthworks must incorporate shallow surface
spoon drains at the base and along the high side of the cut. Backpropping to retaining walls should be
provided throughout the backfilling and compaction process. Drains must have an efficient outflow down-
slope and clear of the 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.




    SCG Consulting Engineers                               2                                 SCG Ref: 32303(S)