Development Application Part 2 of 2 Planning report Geotechnical report and plans MCU11/0168 & OPW11/0257

                                        PRACTICE NOTE GUIDELINES FOR LANDSLIDE RISK MANAGEMENT 2007
                                                                APPENDIX C: LANDSLIDE RISK ASSESSMENT
                                     QUALITATIVE TERMINOLOGY FOR USE IN ASSESSING RISK TO PROPERTY


   QUALITATIVE MEASURES OF LIKELIHOOD

Approximate Annual Probability
                                               Imp lied Indicative Landslide
                                                                                                                         Descri p tion                                         Descri p tor           Level
Indicative           Notional                      Recurrence Interval
  Value              Boundary
   10'                                          10 years                                The event is expected to occur over the design life.                               ALMOST CERTAIN               A
          Z             5 x 10-1                                      20 years          The event will probably occur under adverse conditions over the
   10'                                         100 years                                                                                                                   LIKELY                       B
                                                                                        design life.
                        5x10 '3                                     200 years
   10 '                      -4
                                               1000 years                               The event could occur under adverse conditions over the design life.               POSSIBLE                     C
                        5x10                                        2000 years
          a                                                                             The event might occur under very adverse circumstances over the
   10                                         10,000 years                                                                                                                 UNLIKELY                     D
                                                                                        design life.
                        5x10 '5                                     20 , 000 y ears
   10 '                                                                                 T h e event i s conce i va bl e b ut on l y un d er except i ona l circumstances
                                             100,000 years                                                                                                                 RARE                         E
                                                                                        over the design life.
   10 * 6                5x1 0                                      200,000 years
                                            1,000,000 years                             The event is inconceivable or fanciful over the design life,                       BARELY CREDIBLE              F
   Note:      (1)   The table should be used from left to right; use Approximate Annual Probability or Description to assign Descriptor, not vice versa.



   QUALITATIVE MEASURES OF CONSEQUENCES TO PROPERTY

  Approximate Cost of Damage
                                                                                                Description                                                                    Descriptor        I    Level
Indicative            Notional
  Value               Boundary
                                           Structure(s) completely destroyed and/or large scale damage requiring major engineering works for
  200%                                                                                                                                                                     CATASTROPHIC                 1
                                           stabilisation. Could cause at least one adjacent property major consequence damage.
                                           Extensive damage to most of structure, and/or extending beyond site boundaries requiring significant
   60%                                                                                                                                                                     MAJOR                        2
                                           stabilisation works. Could cause at least one adjacent property medium consequence damage.
                        40%
                                           Moderate damage to some of structure, and/or significant part of site requiring large stabilisation works.
   20%                                                                                                                                                                     MEDIUM                       3
                                           Could cause at least one adjacent property minor consequence damage.
                         10%
   5%                                      Limited damage to part of structure, and/or part of site requiring some reinstatement stabilisation works.                      MINOR                        4
                         1%
                                           Little damage. (Note for high probability event (Almost Certain), this category may be subdivided at a
  0.5%                                                                                                                                                                     INSIGNIFICANT                5
                                           notional boundaryof0.1%. See Risk Matrix.)
   Notes:     (2)   The Approximate Cost of Damage is expressed as a percentage of market value. being the cost of the improved value of the unaffected property which includes the land plus the
                    unaffected structures.
              (3)   The Approximate Cost is to be an estimate of the direct cost of the damage, such as the cost of reinstatement of the damaged portion of the property (land plus structures), stabilisation
                    works required to render the site to tolerable risk level for the landslide which has occurred and professional design fees, and consequential costs such as legal fees, temporary
                    accommodation. It does not include additional stabilisation works to address other landslides which may affect the property.
              (4)   The table should be used from left to right: use Approximate Cost of Damage or Description to assign Descriptor, not vice versa


  91                                                            Australian Geomechanics Vol 42 No 1 March 2007