Slope Stability Assessment Existing Earthworks - OPW21-0279

Anthony Kelly                                                                                               21354-001-Rev0
                                                                                                         17 September 2021

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 and aerial photos.

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 slope stability and existing
structures. The walk-over survey was carried out by an experienced engineering geologist from Tectonic
on 14 September 2021.

The results of the desk-top study and walk-over survey are included in Section 2 below.

1.3    Qualifications of Responsible Engineer
This report has been reviewed by Mr Ashley Davey, an RPEQ with more than 26 years’ experience in
geotechnical engineering, including a number of slope stability projects.


2.0      DESCRIPTION OF EXISTING CONDITIONS
2.1    Geology and Subsurface Conditions
The 1:100,000 scale Gympie Special Geological Map 1 (Ref. Text Figure 3 below) indicates that the site is
underlain by early to middle Triassic age meta-sedimentary geology (‘arenite, argillite, phyllite’) of the Kin
Kin Beds (pale green blue shading).




                                                                                                   Approx. site location




Text Figure 3: Extract of Gympie Special Geology Map

Where minor exposures could be observed through hydromulched cut batters, it was noted that the
materials generally comprised pale grey to pale orange brown and pale red brown, silty clay, occasionally
with gravel. This is in line with the mapped geology at the site.




1
 State of Queensland, Department of Mines and Energy, Gmypie Special 1:100,000 Geological Series, Sheet 9445 and Part 9545, First
Edition 1999




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