Slope Stability Report

Fills ‐ Minimise height.

       Support filled batters with engineered retaining walls or profile to an appropriate slope. For
        this site, exposed fill batters are to be profiled no greater than the following :‐
                                  Safe Batter Profile Angles/ Heights
                      Material         Temporary Permanent Maximum Unsupported
                                                                      Batter Height
            Uncontrolled Fill            1V : 2H         1V : 4H          1.0 m
            Engineered Controlled Fill   1V : 1H         1V : 2H          2.0 m
                      Note: The safe batter profile angles given are for un‐surcharged batters only.

       Strip vegetation, topsoil and key/ bench the natural slope prior to filling. Fill is not to be simply
        placed onto sloping surfaces greater than ~ 7 degrees.
       Use clean fill materials and compact to engineering standards. Fill should be placed in
        maximum 200 mm deep layers and be compacted to a minimum of 95 % Standard Maximum
        Dry Density for cohesive (clay) material or 70 ‐ 90 % Relative Density for non‐cohesive (sand)
        materials.
       Structural filled batters should be over constructed by filling beyond the required final batter
        face and cut back/ trimmed enabling machines to adequately compact the entire fill batter.
       The finished platform must not slope towards the filled embankment which will allow water
        to flow/ cascade over the exposed face. Ponding water on the platform must also be
        avoided.
       Consideration must be given to ensure that no surcharge loading from proposed filling is
        imposed onto any existing infrastructure (including retaining walls, sewer and storm water
        infrastructure etc..) unless it can be shown that measures have been implemented to
        protect the stability of these structures during and after construction. This should be
        determined by the design engineer.


7.3 Foundations

       Footings should be founded within the medium dense to dense sand profile. This is to be
        determined by the designing engineer.
       The design engineer should consider the location of the existing swimming pool and
        retaining walls to ensure that no additional surcharge is imposed on these structures as a
        result of the proposed development.
       On site foundation inspections including footing, slab & retaining walls must be undertaken
        by a suitably qualified and experienced Geotechnical Engineer.

7.4 Drainage
The control of surface and subsurface water is critical to the overall performance of this site. All
surface and subsurface water must be captured and directed off site via a suitable outflow. Water
MUST not be left to pond on site, nor is water to be left to cascade over any cut or fill batter. Some
basic guidelines include but are not limited to:‐

Surface
     Provide drains at the top of all cut and fill slopes, including those retained.
     Discharge under controlled conditions (i.e. pipe) to the street drainage.
     Provide and maintain general falls within drains to prevent blockage by siltation.
     Line spoon drains to minimise the infiltration of surface water and make drains flexible
        where possible.