Appendix B - Geotechnical Investigation Report

                                                  Site Location




                       Plate 4: Extract of the Landslide Hazard Overlay Map OM-LS-14B

Based on our site observations:
     There were signs of near surface creep of the steeper central portion of the site indicated by leaning
      trees and trees with curved bases. However, there were no obvious signs of potential deeper slope
      instability such as tension cracks in the slope surfaces.
     There were no obvious signs of retaining wall instability such as tension cracks behind the wall crests,
      bulging faces etc although our observations were limited by the overgrown nature of some areas of the
      site. However, we have assumed that the retaining walls within the site were engineer designed.

We have no information regarding the placement of the fill on the site and as such it has been assessed as
being ‘uncontrolled’ as defined in AS2870-2011. As noted in Section 4.2 above we also assessed the fill to be
poorly compacted based on the DCP test results.



5.2     Risk Assessment

5.2.1 Potential Geotechnical Hazards
Based on our site observations, assessment of existing conditions provided above, and the form of the
proposed residence, we consider that the potential geotechnical hazards for the site, may be summarised as
follows:
1. Deep seated instability.
2. Slow moving near surface creep of the steeper section of the site.
3. Instability of existing retaining walls.
4. Instability of temporary excavation batters.
5. Instability of new retaining walls.

It is important to be mindful that slope instability can occur at any time and it would be difficult or impossible
to predict when the identified potential hazards will occur. Also, we cannot predict when an extreme or
unusual event may occur (such as an earthquake or 1 in 100 year rainfall event etc) and what impact it would
have on the stability of the identified potential hazards described above.


35891URrpt Rev1                                     6