Landslide Hazard Report_compressed

Specialists in transport geotechnics

Table 5 summarises qualitative assessment of slope instability risk prior to any remedial works or
engineering controls. Table 6 shows the assessed qualitative risk following appropriate
engineering controls and practices in design and construction, risk management, including
earthworks in accordance with the guidelines in this report.


  Table 5: Results of Qualitative Assessment of Risk to Property - Without Engineering Controls
                                                                             Without Engineering Controls
       Potential Hazard                                                               Likelihood of
                                       Elements at Risk                                                Qualitative Risk
                                                                 Consequence           Occurrence



   -   Shallow failure             Elements in proposed            Medium                 Unlikely              Low
                                     building envelope


   -   Deep seated failure
       within the residual soil    Elements in proposed                                                         Low
       profile                                                      Major                   Rare
                                     building envelope


  Table 6: Results of Qualitative Assessment of Risk to Property - With Engineering Controls
                                                                                  With Engineering Controls
                  Engineering Controls to Reduce Risk                                  Likelihood of
                                                                 Consequence                             Qualitative Risk
                                                                                        Occurrence
          -    Provision for good drainage and erosion
               control measures i.e. surface water interceptor
               drains and flow spreaders.                           Minor                  Rare
          -    Plant ground cover over natural slopes to
                                                                                                              Very Low
               reduce erosion over time.
          -    Structure piers to be founded in hard residual
               soils

          -    Keep additional structures away from the crest
               of steep bushland land to the North                                         Rare                 Low
                                                                   Medium
          -    Manage drainage
          -    Limit land clearing

4.2 Effects of Development on Land Stability
4.2.1 Existing Conditions
Existing conditions are discussed in section 3 above.

4.2.2 Effects
Based on observations made in the field, the effect on land stability due to the proposed
development is considered to be low should good construction practice be followed during
construction.
Site drainage around the development in the form of swale drains to minimise effects of erosion
should be included.




10 May 2022                                CGC-SR-2022-011-R01-Rev01                                          Page 12