Appendix F - Geo-Environmental Investigation Report · RAL24/0003

                                            PROPOSED SUBDIVISION
                                            41 TALLOWWOOD PLACE, BLACK MOUNTAIN

Table of Contents

1.0   INTRODUCTION ........................................................................................................................................................ 1

2.0   PROPOSED DEVELOPMENT ................................................................................................................................... 1

3.0   AIMS & METHOD OF INVESTIGATION ................................................................................................................... 2

      3.1         Fieldwork ...................................................................................................................................................... 2

      3.2         Laboratory Testing ........................................................................................................................................ 2

4.0   RESULTS OF INVESTIGATION ................................................................................................................................ 3

      4.1         Site Description............................................................................................................................................. 3

      4.2         Topography................................................................................................................................................... 4

      4.3         Geology ........................................................................................................................................................ 7

      4.4         Subsurface Conditions.................................................................................................................................. 7

      4.5         Geotechnical Laboratory Test Results .......................................................................................................... 8

      4.6         Groundwater ................................................................................................................................................. 8

      4.7         Surface Drainage .......................................................................................................................................... 8

      4.8         Vegetation .................................................................................................................................................... 8

      4.9         Buildings and Other Structures ..................................................................................................................... 9

5.0   SLOPE STABILITY ASSESSMENT .......................................................................................................................... 9

      5.1         Existing Conditions ....................................................................................................................................... 9

      5.2         Slope Stability Assessment ........................................................................................................................ 10

      5.2.1            Qualitative Assessment......................................................................................................................... 10

      5.2.2            Numerical Modelling.............................................................................................................................. 11

6.0   GEOTECHNICAL RECOMMENDATIONS .............................................................................................................. 13

      6.1         Site Layout and Geotechnical Constraints .................................................................................................. 13

      6.2         Earthworks .................................................................................................................................................. 14

      6.2.1            Site Preparation and Trafficability ......................................................................................................... 14

      6.2.2            Excavations ........................................................................................................................................... 14

      6.2.3            Batter Slopes ........................................................................................................................................ 15

      6.2.4            Filling..................................................................................................................................................... 15

      6.3         Building Foundations .................................................................................................................................. 16

      6.3.1            Site Classification .................................................................................................................................. 16

      6.3.2            Footing Design ...................................................................................................................................... 16

      6.4         Retaining Structures ................................................................................................................................... 17

      6.5         Drainage ..................................................................................................................................................... 18



22 May 2023
Report No. 23099-001-Rev0                                                              iii