Geotechnical Investigation

                               PROPOSED CALILE HOTEL NOOSA DEVELOPMENT
                               3 – 7 SERENITY CLOSE, NOOSA HEADS




Text Figure 1: Level four layout plan (upper) and some cross-sectional views (lower) of the development, courtesy of
Richards + Spence

3.0      METHOD OF INVESTIGATION
As part of our assessment, a desk-top study was carried out comprising a review of published geological
maps, slope stability studies as well as Noosa Council (NC) planning overlays and site information.

An experienced geotechnical engineer from Tectonic undertook a site walk-over on 21 June 2022 to visually
assess any indicators of past slope instability. The walk-over included assessment of soil exposures,
surface drainage conditions, topography, evidence of erosion or past instability, and vegetation
coverage/condition.

This was followed by a subsurface investigation comprising the drilling of ten boreholes (designated BH1 to
BH10) in accessible areas across the site. Boreholes were drilled using Tectonic’s 4WD mounted solid flight
auger rig, and hand augering equipment, to depths between 3 m and 6 m below ground level (BGL).

In-situ testing, using the dynamic cone penetrometer (DCP) method, was carried out from the ground surface
adjacent to and within each borehole, with DCP testing continued beyond the borehole termination depths in
borehole BH4 and BH9. Boreholes were backfilled on completion using spoil arising during drilling, with
excess material slightly mounded at surface.

Borehole locations are shown in Figure 1 attached at the end of this report, with borehole and DCP logs
presented in Appendix A, together with explanatory notes. Borehole coordinates were recorded using a
handheld global positioning system (GPS) with an accuracy of ± 3 m.

Selected soil samples were dispatched to a NATA accredited laboratory for geotechnical testing. Laboratory
testing was undertaken in accordance with Australian Standard AS1289 Methods for Testing Soils for
Engineering Purposes and comprised two particle size distribution (PSD) tests for soil classification.
Geotechnical laboratory test results are summarised in Section 4.5. Laboratory certificates are attached in
Appendix B. The results of the desk-top study and walk-over survey are included in Section 4 below.




7 October 2022
Report No. 22239-001-Rev0                                  2