MCU14/0106 Appendix E - Engineering Report

August 2004 -2- 04682104(AB)

 

3.0 PROPOSED DEVELOPMENT

A drawing showing the proposed development layout and site profiling plan for Stage 1 has
been provided to us by MPN (Dwg. No. 4024, 55, Rev. B). We understand that the proposed
bulk earthworks will include cutting up to about 3.5 m depth across the northern ridge and
filling around the perimeter to depths of up to about 3 m. The finished surface level across the
site will range between about RL 6 mand RL 10 m AHD.

The proposed buildings will comprise low-rise structures located primarily in cut around the
northern part of the site and on a fill platform around the southern part. We understand that
Tetaining walls up to about 3 m in height may be constructed around the southern edge of the fill
platform. The central part of the site will contain pavements for car parking and access roads,
together with areas of landscaping. It is understood that excavations are proposed in the
southern part of the site (below RL 5m AID) to form detention basins / ponds.

4.0 METHOD OF INVESTIGATION
41 Preliminary Assessment

To assist with planning the level of detail required for the ASS component of the investigation a
desktop study was undertaken. ‘

The desktop assessment comprised a review of available published reports and plans on geology
and acid sulfate soil distribution. The findings from this preliminary assessment are presented in
Section 5.1.

4.2 Field Work

Eighteen test pits (designated GA1-18) and three boreholes (GA19-21) were conducted across ,
the site. The test pits were dug using a 6 tonne excavator with 350 mm toothed bucket, whilst
the boreholes were drilled using a 4WD-mounted flight auger rig. The test pits and boreholes
were generally extended to depths of between 3 m and 5 m, with the depth investigated
dependent upon the extent of cut or fill proposed at each location.

The ASS component of the investigation program was planned in accordance with State
Government policies! and legislation to cover the areas of significant filling and excavation
below RL 5 m AHD in the southern part of the site. The formulation of our scope of work is
discussed in Section 7.2,

 

' State Planning Policy SPP2/02 “Planning and Managing Development Involving Acid Sulfate Soils,

Golder Associates