Mission River Bridge Reinstatement

Scope of Work

PMG has recently completed an extensive underwater repair campaign on the Mission River Bridge in Weipa for RioTinto / Comalco.

Since 1997 Pacific Marine Group has completed 10 off 3 month diving and marine construction campaigns. Up to 20 marine, dive and support crew are involved in the project in any 1 year.

Works completed during the project have included:

• Extensive underwater welding / cutting
• Extensive splinting of piles - Installation of steel splint shells and filling with epoxy grout
• Cathodic Protection system installation and maintenance
• Denso pile protection products installation
• Inspection / underwater NDT / photography / video inspection

The Mission River is home to many salt water crocodiles and other dangerous marine animals. Safe access to the piles has always been an issue, and Pacific Marine Group has continually looked at ways to improve safety. Part of this process has seen the design and refinement of a “predator protection pontoon” or PPP. A 40mx25m floating pontoon forms the diver support area around each pier and is serviced by the dumb barge PMG1. 500mm x 500mm rope mesh nets are suspended below the pontoon down to the seabed to provide protection. These nets can be raised / lowered as required to facilitate moving to the next pier. The barge and pontoon are kept in place using a network of anchors. The pontoon is winched to subsequent piers by opening one side of the PPP.

Pacific Marine Group is very aware of RioTinto’s Safety standards and requirements, and has worked under this safety system for over 15 years. We have an excellent safety record on this very challenging marine and underwater project, and have maintained an excellent working/contractual relationship with RioTinto.