geotech

                              PROPOSED UNIT DEVELOPMENT
                              9 BOTTLEBRUSH AVENUE, NOOSA HEADS

In-situ testing, using the dynamic cone penetrometer (DCP) method, was carried out from the ground surface
and within each borehole. DCP testing was extended below the base of the hand augered boreholes to
depths between 4.6 m and 4.8 m BGL. Boreholes were backfilled on completion with spoil arising during
drilling, with excess material slightly mounded at surface.
Laboratory testing was not warranted due to the sandy nature of the subsurface conditions encountered.

Borehole locations are shown in Figure 1 attached at the end of this report, with borehole and DCP logs
presented in Appendix A, together with explanatory notes. Borehole coordinates were recorded using a
handheld global positioning system (GPS).

The results of the desk-top study and walk-over survey are included in Section 4 below.


4.0      RESULTS OF INVESTIGATION
4.1      Site Description
The site is formally described as Lot 147 on RP88934, covering an area of 506.65 m2, with frontage to
Bottlebrush Avenue along the south-western boundary. At the time of the investigation a two-storey
residential unit building occupied most of the central part of the site, with a dilapidated asphalt sealed
driveway providing direct access off Bottlebrush Avenue. A timber retaining wall supported the north-eastern
boundary, with timber fencing tracing the northern, eastern, and western site boundaries.

Based on a visual assessment the existing building was noted to be in good structural condition exhibiting no
obvious signs of distress (e.g. cracking, misalignment, etc.). Dilapidation was evident across the existing
driveways, retaining walls and fencing, which appeared to be related to age, poor construction and possibly
consolidation of the upper loose sands.

Similar residential unit developments and houses occupied properties to the north, east and west of the site.
It appeared that the surrounding unit buildings comprised mostly at grade carparking, with the lower level
partially excavated into the hillside. Based on a visual assessment, it appeared that excavations up to about
3 m deep had been undertaken on neighbouring properties. Observable walls appeared to be in relatively
good structural condition, based on an external assessment. It was noted that part of a concrete pathway,
kerb, and channel on the opposing (southern) side of Bottlebrush Avenue displayed horizontal/vertical
separations. It appeared that this distressed was due to consolidation of fill materials, which are inferred to
have been placed during the construction of the road.

A 2021 aerial image of the site and surrounds is shown in Text Figure 2 below.




                                                                          Subject Site




Text Figure 2: 2021 aerial image of the site and immediate surrounds (courtesy Nearmap imagery)



13 July 2021
Report No. 21169-001-Rev0                                2