Good progress is being made by the two dredges being used for Phase 2 of the dredging and, at this stage, this phase of the dredging should be completed well before the contracted completion date of 19 November.
Specialist dredging company Boskalis Australia Pty Ltd is using two of its most sophisticated dredges to ensure the dredging can be undertaken efficiently while the port continues to operate.
The entrance to Rous Head Harbour has been successfully dredged without interference to Rottnest ferries. Most of the Entrance Channel dredging has been completed. Crushing activities by Phoenix are well ahead of schedule and the only remaining areas to be crushed are off C and D Berths.
The Gateway is focussing its efforts on removing crushed rock where access is possible, otherwise it is being utilised to remove remaining high spots in the harbour and Deepwater Channel.
Ongoing inspections of coastal and river beaches indicate that the coastal beaches are largely unaffected by the dredge plume. There was increased cloudiness in the river up to about Bicton Baths on Friday 8 October due to Gateway working at the eastern end of the harbour. This cloudiness might continue as the removal of this material is completed.
Signs have been posted at nearby river beaches advising swimmers to take care when entering the water due to the potential for reduced visibility at times.
Ongoing monitoring throughout the dredging program has confirmed that there are no ecosystem or public health threats.
Monitoring results are posted weekly on the Fremantle Ports website and include results from mussel sampling for both sentinel mussels (ie. clean mussels placed in the water for a period of six weeks) and wild mussels.
Results showed that concentrations of contaminants in both sentinel and natural mussels were below laboratory detection limits in the majority of cases and where detected did not exceed trigger levels relevant to the protection of fishing and aquaculture values.
Source: fremantleports, October 11, 2010