Slope Stability Assessment Existing Earthworks - OPW21-0279

Anthony Kelly                                                                                21354-001-Rev0
                                                                                          17 September 2021

2.2   Topography
As illustrated in Text Figure 4 below, the topography over the wider site area is largely dominated by a well
defined, rounded ridgeline, extending from further south; to around 450 m north of the subject site boundary
where it dips down to meet Six Mile Creek. The western flank of the spur dips down from the crest generally
at around 12° to 15°, shallowing significantly towards Lawnville Road, where the ground transitions to
relatively flat alluvial ground associated with Six Mile Creek. The eastern flank dips more steeply at between
15° and 25° towards the invert of a prominent, and intermittently dammed gully line.




                                                                                                          Localised gully in
                                                                                                          flank




                             Six Mile Creek




                                                                                             Prominent gully
                                                                                             invert




Text Figure 4: Image showing ground surface contours (courtesy NC Interactive Maps)

As mentioned above in Section 1.1, there were four broad areas of the development undertaken thus far,
which are described individually below.

The driveway extension to the south-west of the site area ran across the ground slope contours, ranging
from 8°close to the existing driveway, and up to about 12° to 15° at the transition to the southern cleared
area. Drains had been formed in cuts, ranging from about 0.5 m to 1 m depth to either side of the driveway.

A view of the driveway extension is shown on the following page in Text Figure 5.




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