Attachment 3 - Geotechnical Report

LOT 21 (16) PINES ROAD, COOROY                                                          EBIS REFERENCE NO: 210417-SU/GEO




                      Figure 5 Weathered rock evident in face of cut embankment

Some minor areas were prone to erosion where the bedding of the weathered rock was
“dipping” down allowing the shalley gravels to come loose.

3.2       Stability Zoning

3.2.1 Risk of Slope Instability/Landslip

The Landslide Hazard overlay map (1) from Noosa Plan 2020 shows this area to be low risk
at the crest of the ridge line above the site to moderate risk across the development area.

NOTE: The council overlays are a “typical” guide to the site conditions in the location
shown in terms of steep land and landslip risk.

Table 1 - Risk Level Implications
           Risk Level                                              Example Implications (1)
VH       VERY HIGH RISK           Extensive             detailed investigation and research, planning and
                                           implementation of site treatment options essential to reduce risk to
                                           acceptable levels; may be too expensive and not practical
H          HIGH RISK                       Detailed investigation, planning and implementation of site treatment
                                           options required to reduce risk to acceptable levels.
M          MODERATE RISK                   Tolerable provided site treatment plan is implemented to maintain or
                                           reduce risks. May be accepted. May require investigation and planning of
                                           various options.
L          LOW RISK                        Usually acceptable. The site treatment requirements and responsibility to
                                           be defined to maintain or reduce risk.
VL         VERY LOW RISK                   Acceptable. Manage by normal slope maintenance procedures.

Note: (1) The implications for a particular situation are to be determined by all parties to the risk assessment; these are only
given as a general guide.

Taken from the AGS Extract containing “Practice Note Guidelines for Landslide Risk
Management 2007”. It is indicated that the local government and government bodies
(councils or other authorities) as regulators have the responsibility or authority to assess
hazards eg; Landslides of potential risk to development of land that is possibly “at risk” and
ensure that the risk levels are properly considered.

If mitigation is required, Planning and Design for the development should include works
which result in acceptable risk levels to property after completion of construction. In some
cases, subject to appropriate monitoring and maintenance programs, a tolerable risk may be
accepted.
PROPOSED NEW RESIDENCE                                  PAGE 6 OF 10                                             4 March 2022