Attachment 5 - Slope Stability Assessment · RAL20/0005

Mr Peter Loxton                                                                               16162-001-Rev0
                                                                                                 22 July 2016

2.3    Groundwater
As mentioned above, groundwater was encountered in the CSI boreholes at shallow depth. The ground
surface across the proposed addition footprint was noted to be relatively saturated at the time of our walk-
over.

2.4    Surface Drainage
Due to the low-lying nature of the site, and very low gradients, surface water run-off is expected to be
relatively slow, leading to the saturated soils observed at the surface and in the CSI boreholes. It is
possible that the site may be subjected to flooding during high intensity rainfall events (this should be
assessed by a suitably qualified and experienced hydraulic engineer). As shown in Text Figure 2 and
illustrated in Text Figure 6, two watercourses not more than about 1 m wide meander across the proposed
building site and held water up to about 0.5 m deep at the time of the walk-over. No signs of soil erosion
were observed during our visit.




Text Figure 6: Existing watercourse

2.5    Vegetation
At the time of the site visit, the proposed building site had a dense canopy of mostly paperbark trees
estimated up to 15 m tall, with a relatively open understorey including palms and ferns. The sloping western
part of the site contained some tall gum trees, with straight and ‘plumb’ trunks (Ref. Text Figure 7).




Text Figure 7: Level area at front of existing residence




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