24-01-2020 - Appeal No. 245 of 2019 - Final Order of Judge Rackemann · 51987.2951.01

McInnes Wilson Lawyers


Table 1: Seismic Data Acquisition Parameters.
 Seismic source:             10 kg sledgehammer on aluminium plate

                             Geode-24 seismograph using Geometrics Seismodule Controller software; 24-bit 24-channel
 Recording system:
                             recorder

 Recording channels:         24 per record


 Sampling rate:              0.25 ms


 Record length:              2 seconds


 Geophone type:              4.5 Hz single geophones


 Initial offset:             12 m

 Source interval:            12 m


 Geophone interval:          1.5 m



    4.2            Borehole Drilling
One borehole (designated BH1) was drilled on 19 July 2019, using a trailer-mounted auger drill rig to a depth
of 13 m below ground level (BGL) (refer Figure 1). Standard penetration testing (SPT) was undertaken at 1.5
m intervals starting from 1 m BGL.
Prior to drilling, a licenced underground service locator was engaged to assess underground services in the
driveway area to select a suitable drilling location.
Driveway pavers were temporarily removed to allow for drill rod access. The borehole was backfilled with
spoil on completion, and the brick pavers then placed back in position.

    4.3            Dynamic Cone Penetrometer (DCP Testing)
Two DCP tests (designated DCP1 and DCP2) were undertaken on 19 July 2019 (refer Figure 1). The DCP
tests were undertaken to practical refusal at about 7 m and 4 m BGL, respectively.

5.0       GEOTECHNICAL INVESTIGATION RESULTS
Reports of Boreholes and DCP Tests are attached in Appendix A.
Seismic survey results for Line 1 to Line 4 are presented as two-dimensional cross sections in the attached
Figure 2.
The ground investigation results indicate that the upper portion of the dune, in the vicinity of the existing
residence/proposed pool, comprises about 1 m to 2 m depth of very loose or loose sand from the ground
surface, over medium dense to very dense sand. The sand shows some variability in density but appears to
generally increase in density with depth. At about 8 m to 10 m below ground level (BGL), the sand typically
becomes very dense and weakly cemented in parts. Groundwater seepage was encountered in borehole
BH1 at about 8.5 m BGL during drilling.
The lower portion and toe of the dune generally encountered about 1 m to 2 m depth of very loose or loose
sand from the ground surface, over medium dense sand. From about 3 m to 4 m BGL, the sand becomes
dense with zones of very dense sand (including inferred cemented sand ‘coffee rock’) and increases in
density with depth. The seismic testing results (Line 3) indicate that the coffee rock is consistently present at
the toe of the dune below the site, but may vary in thickness and density. Coffee rock is generally
significantly more resistant to erosion than typical beach or dune sands. This is evidenced by its long term
(years) exposure at around mean sea level at many locations along the sunshine coast. Refer to the
information box below for further, general information on coffee rock.


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