Attachment 5 - Geotechnical Assessment · MCU18/0015

RTI 11/055 Folio B385

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1.0 INTRODUCTION
This report details the results of a geotechnical investigation carried out by Golden Ass

Pty Ltd (Golder) for a proposed Group Housing Development and Accommodation Buildi gz
at 26 Attunga Heights, Noosa Heads. The investigation was undertaken for Mr Phillip
Harding (Attunga Heights Pty Ltd) at the request of Victor G Feros, town planning
consultants for the project.

  

The development proposal comprises construction of Group Housing, an Accommodation
Lodge and two minor access roads, which bridge the creek. This report presents the results of
the site investigation and a slope stability assessment together with geotechnical advice
regarding earthworks, retaining structures, footings, pavements, drainage and other
construction matters.

2.0 SITE DESCRIPTION

The real property description of the site is Lot 27 on. RP\89506, Parish of Weyba and covers
an area of about 1.8 hectares. Attunga Heights and Picture Point Crescent terminate adjacent
to the southern and western site boundaries respectively. The site is bounded by residential
properties to the south and west, Halse Lodge (north) and the Viridian Noosa site (east).

Figure 1 shows the proposed development, layout overlain on the site plan, which includes
ground surface contours and the positions of trees. The base plan for Figure | is derived from
JMA Architects Drawing No. 978DA0001 Rev. B) dated 2 October 2003.

The majority of the site’ is.a moderately-to steeply sloping sand dune slope (with an easterly to
north-easterly aspect), intersected by.a meandering creek, which runs from the south towards
the north adjacent to the eastern site boundary. The dune slope has a maximum elevation of
about RL 58 m in the south-western corner of the site, with a minimum recorded elevation of
about RL 10 m in the bed of the creek adjacent to the northern boundary. Ground slopes
across the dune typically\range between about 20° and 30°, as shown in Photograph 1, with
steeper slopes of up to.40° occurring adjacent to the banks of the creek.

Boulders of diorite up to 800 mm across are exposed in the western bank of the creek in the
northern part of the site. A massive outcrop of diorite is exposed in the bed of the creek
adjacent to the middle of the eastern site boundary. There is also an approximately 1 m deep
outcrop of colluvium (clay and rock), shown in Photograph 2, exposed beneath about 1 m of
sand in the bank of the creek adjacent to the northern site boundary. This outcrop is located
on a relatively sharp bend in the creek below a possible landslip within the dune sand. The
approximate extent of the possible landslip is defined by ground sloping at about 40°, across
which a number of mature trees were observed to have bent trunks indicative of previous
ground movement.

Golder Associates

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