RFI - slope stability reporting

RECOR Pty Ltd                                                                                 22393-001-Rev0
                                                                                              26 October 2022

1.2       Method and Scope of Investigation
As part of our slope stability assessment, a desk-top study was carried out comprising a review of published
geological maps, slope stability studies and available geotechnical data. A walk-over survey was conducted
in order to make an appraisal of the general condition of the site in regard to topography, drainage,
vegetation cover, geology, erosion, and condition of existing structures.
The walk-over survey was carried out by an experienced geotechnical engineer from Tectonic on
7 October 2022. The walk-over assessment was combined with a geotechnical investigation comprising two
boreholes (designated BH1 and BH2) undertaken by hand auger methods in accessible areas across the
site to 3 m below ground level (BGL). The approximate locations of the boreholes are shown in Figure 1
attached at the end of the report text. In situ testing, using the dynamic cone penetrometer (DCP) method,
was carried out from the ground surface and at select intervals downhole. DCP testing extended below the
borehole termination depths unit practical refusal was achieved.

The borehole logs and explanatory notes are attached to this report. The results of the desk-top study, walk-
over survey and borehole drilling are included in Section 2 below.

1.3       Qualifications of Responsible Engineer
This report has been reviewed by Mr Ashley Davey, an RPEQ with over 27 years of experience in
geotechnical engineering, including a number of slope stability projects on the Sunshine Coast.



2.0        DESCRIPTION OF EXISTING CONDITIONS
2.1       Geology and Subsurface Conditions
Available geological information 1 indicates that the site is underlain by Pleistocene age parabolic sand dunes
comprising “quartz sand” (Ref. Text Figure 3).




                                                                     Approx. Site Location




Text Figure 3: Extract from Laguna Bay Surface Geology Map




1
    1:100,000 Laguna Bay Surface Geology, Sheet 9545, Compilation Map, DNRME, 2018




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