Appendix E_Geotechnical Investigation

                              PROPOSED UNIT DEVELOPMENT
                              PRECINCTS E2 & F, NOOSA SPRINGS



Executive Summary
This report details the results of a geotechnical investigation undertaken for a proposed development of
Precincts E2 and F located on Resort Drive, Noosa Springs (Lots 6 and 7 on SP178340). The investigation
was performed by Tectonic Geotechnical Pty Ltd (Tectonic) for Altum Constructions. This report summarises
the results of the investigation and includes a slope stability assessment. Recommendations are provided
regarding design of earthworks, retaining structures, footings, and drainage.

It is our understanding that the proposed development layout for both Precincts E2 and F is preliminary and
is subject to change. Preliminary architectural drawings indicate that the Precinct E2 development will
comprise construction of multiple units within seven buildings. Access to the development will be gained via
a new driveway from the end of the Resort Drive cul-de-sac. The Precinct F development comprises a
central common area (restaurant, stores, staff facility, pool) surrounded by residential units. Access will be
from Resort Drive.

The site investigation comprised a walk-over survey combined with drilling of thirteen boreholes to depths
ranging from 5 m to 6 m below ground level (BGL). The subsurface conditions encountered in the boreholes
can be divided into two distinct areas, being Areas 1 (ridge and flanks of ridge) and 2 (flat area at toe of
slope).

Area 1 mostly comprised natural very loose to loose silty sand/sand to depths of up to 1.6 m BGL, overlying
medium dense to very dense silty sand/sand to depths up to 6.0 m BGL, with very dense indurated sand
from a depth of 5.5 m BGL in borehole BH7 only.

Area 2 encountered uncontrolled fill consisting of loose medium dense silty sand and stiff sandy clay, with
some building rubble and green waste, to depths up to 3.6 m BGL (up to 5 m in Soil Surveys Engineering
2000 investigation); then natural medium dense to very dense sands.

Groundwater seepage was only observed in Boreholes BH6 and BH7 at depths of 4.6 m and 5.5 m BGL,
respectively.

Based upon the existing site conditions, and subject to the implementation of recommendations given within
this report, it is our assessment that building sites with a Low (L) Risk of global slope instability (with a
factor of safety against slope instability of at least 1.5) are achievable. The extent of building (unit
construction) works, including cut/fill, must be limited to maintain slope stability. Control of stormwater flows
via channels and/or pipes will also be essential to maintain slope stability.

Investigation results indicate that future operational and/ or building works, including service trenching
together with the limited building earthworks, should be possible by adopting conventional earthmoving
equipment (e.g. large tracked excavators).

Based on the results of the investigation, the indicative site classification for this site is Class P in
accordance with AS 2870-2011 Residential Slabs and Footings, due to the existing steep slope and
uncontrolled fill. If not for the uncontrolled fill and steep slopes the site would have the characteristics of a
Class M site in accordance with AS2870.

Depending on the extent of future earthworks, footings for all structures in Area 1 should be founded on
screw piles or bored piers taken at least 3 m into natural medium dense (or denser ) sands and be designed
for an allowable bearing capacity of 300 kPa. Footings for structures in Area 2 will be dependent on the
extent of removal and replacement of uncontrolled fill.

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. Excavations in medium dense (or denser) sands may be battered
at 1V:2H.




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