081128 - Lots 5 - 8 Soil Tests · OPW18/0155

                                  LOTS 5 TO 8, SETTLERS COVE, SERENITY CLOSE, NOOSA



1.0         INTRODUCTION
This report details the results of a geotechnical investigation carried out for a proposed unit development at
Lots 5 to 8, Settlers Cove, Serenity Close, Noosa Heads. The investigation was undertaken at the request of
Tate Professional Engineers Pty Ltd (Tate), the consulting engineers for the project, on behalf of the client
CBD Settlers Cove Pty Ltd.
Information supplied to us by Tate indicates that the proposed development comprises two and four level
structures of masonry construction, a pool and associated infrastructure. The four storey buildings will be
over single level, slab on ground basements. We are advised that stormwater disposal for the site will be via
Rapid Infiltration Pits (RIPs) which discharge through a permeable base no less than 2 m below the ground
surface.
This report summarises the results of the investigation and includes an assessment of slope stability
together with geotechnical recommendations regarding the design of earthworks, footings, retaining
structures and pavements.



2.0         SITE DESCRIPTION
Site is located at the western end of Serenity Close, Noosa Heads.
At the time of the investigation (Ref. Photograph 1 below), the proposed development area was covered by
grass and mulch with stands of vegetation. The ground surface sloped towards the south and south west at
angles of between about 5o to 8o. The ground slope increases (up to about 35º) in the southern and western
parts of the site within densely vegetated land down to Noosa Inlet.
The site layout, together with ground surface contours and photographs illustrating the site conditions at the
time of the investigation are shown on Figure No. 1.



3.0         METHOD OF INVESTIGATION
The investigation comprised a terrain assessment by a senior geotechnical engineer together with a
subsurface investigation by geotechnical personnel carried out between 29 to 31 October 2008. The
subsurface investigation comprised twenty boreholes (designated BH1 to BH20) drilled using a 4WD
mounted solid flight auger rig to depths of 6 m.
In-situ soil density was assessed by conducting dynamic cone penetrometer (DCP) tests from the ground
surface adjacent to each borehole and at various depths within the boreholes following augering (in order to
minimise the effect of rod friction on the test results).
Borehole locations are shown in Figure No. 1, Site Plan. Results of the fieldwork are presented in the
Reports of Boreholes in Appendix A, along with explanatory notes.



4.0         SUBSURFACE CONDITIONS
Available geological information1 indicates that the site is underlain by Quaternary (Pleistocene) age quartz
dune sand.
The subsurface conditions encountered in the boreholes generally comprised very loose to loose sand to
depths of between 0.4 m to 2.3 m, then dense sand to between about 2.7 m and 4.1 m depth, underlain by
medium dense to dense sand to the depth of investigation (ie. about 6 m).


1
    1:100,000 Geological Map, GYMPIE SPECIAL, Sheet 9445 & Part 9545, DME, 1999


December 2008
Report No. 087682058 002 Rev.1                                1