Geotechnical and Environmental Investigation of the Eden Breakwater Wharf Extension Site

Vibrocores shall be carried out to a depth of -12m CD or until refusal in rock is reached, whichever comes first.

Indicative borehole depths and drilling direction are as follows:

Borehole Number  Depth (CD)      Drilling Direction

1         -30m           Vertical Borehole
2         -30m           Inclined Borehole
3         -30m           Vertical Borehole
4         -30m           Vertical Borehole
5         -30m           Vertical Borehole
6         -12m           Vertical Borehole
7         -12m           Vertical Borehole

Table 1:- Indicative borehole depths and drilling direction

The geotechnical site investigation shall obtain geotechnical data including physical soil parameters which shall:

* Enable the concept design to progress and provide engineering inputs for the detailed design process specifically:
* Slope stability and dredge batter design
* Dredging cost estimates
* Pile drivability analysis
* Pile design
* Stability of adjacent structures studies
* Provide more accurate cost estimates of dredging and pile installation costs.

The environmental samples shall provide geochemical data of the proposed dredged material which are required to support statutory approvals in relation to dredge spoil disposal. The environmental samples shall be taken from vibrocores.

Additional geophysical surveys shall also be carried out. A side scan sonar survey shall be carried out to create images of the seafloor and the submerged sections of the breakwall and a magnetometer survey shall be carried out to detect the presence of ferrous objects on or beneath the seabed.

The Contractor shall supply and operate an appropriate jack-up barge (JUB) and barge mounted drilling rig which enables the Contractor to carry out the drilling activities.

The Contractor shall also supply and operate a suitable work-boat capable of carrying out a side scan sonar survey, magnetometer survey and vibrocoring.