Appendix E_Geotechnical Investigation

                             PROPOSED UNIT DEVELOPMENT
                             PRECINCTS E2 & F, NOOSA SPRINGS

7.0      ENGINEERING ASSESSMENT
7.1      Development Limitations
In order to achieve a FOS against slope instability of at least 1.5, with a consequent Low Risk, on the sloping
part of the site, and to provide a suitable building platform on the flatter area, development limitations must
be implemented. The following limits shall apply:

       No filling is to be undertaken on the sloping ridge or flanks of the ridge, unless assessed and
        approved by a suitably qualified and experienced geotechnical engineer. Any filling will need to be
        supported by an engineer designed retaining wall.
       All footings must be founded within the dense sand layer.
       Remove all uncontrolled fill and replace with select, compacted and certified fill.
       Once the design for building layouts and earthworks are finalised, this report will need to be reviewed
        to confirm the recommendations provided herein.

7.2       Earthworks
7.2.1        Site Preparation and Trafficability
Following clearing of vegetation, trees stumps and large root must be ‘grubbed out’ and any organic rich
topsoil stripped from the construction area, along with any existing uncontrolled fill. Organic topsoils and
garden soils must not be re-used in structural fill, however may be retained on site for later use across
landscaping areas, if required.

Note: Where no buildings are proposed, vegetation is not to be removed, and any bare areas must be
planted out. Bare areas may require covering with jute matting (or similar) to allow for re-growth of plants.

Additional deeper stripping will be required in the flatter area (Area 2) to remove the uncontrolled fill. SSE
boreholes indicate uncontrolled fill to depths up to about 5 m, but mostly less than 2 m.

After stripping, the subgrade is expected to comprise natural loose to medium dens or dense sand.
Following stripping and bulk excavation (depending on scope of earthworks), the subgrade must be
inspected by a suitably qualified and experienced geotechnical engineer to determine whether any site
improvement (e.g. compaction and/or over-excavation and replacement) is required to achieve a stable
subgrade for construction activities.

The site should be graded to shed surface water runoff away from construction areas. Swale drains should
be constructed along the toes of any cuts, and above cuts where possible, with the drains graded to
discharge collected waters to a control point before release off-site.

Appropriate erosion and sediment control measures must be installed prior to commencement of earthworks
at this site.

7.2.2        Excavations
The scope of future excavations was not known at the time of reporting. However, it is assumed that
excavations will be required to depths up to about 5 m BGL to remove uncontrolled fill, and up to about 2 m
to 3 m depth to provide suitable building areas and pavements

Excavations in fill and natural sands should be achievable using conventional earth moving equipment (e.g.
large tracked excavators).

Temporary cuts in very loose to loose sands may be formed no steeper than 1V:2H, with permanent batter
slopes in such materials formed at 1V:3H. Flatter batters may be required if groundwater seepage is
encountered, or if earthworks are undertaken during a period of heavy rainfall.

Temporary excavations in medium dense (or denser) sands may be battered at 1V:1H, with permanent
excavations in such material to be no steeper than 1V:2H. Flatter batters may be required if groundwater is
encountered, or if excavations are carried out during/following wet weather.




11 November 2015
Report No. 15193-002-Rev0                              12