Fremantle Port Inner Harbour and Channel ... - Fremantle Ports

• Coral/seagrass monitoring teams will be informed of the exceedance and the potential
need for upcoming monitoring.
Level 4 Management Response:
• Where LAC is determined to be above the Level 4 trigger levels, then the exceedance
will be noted in fortnightly reporting (by the Environmental Monitoring Contractor) to
Fremantle Ports and the Office of the EPA;
• The exceedance will be investigated and management strategies will be developed
(e.g. additional silt curtains, raising of weir box to lower flow rate of return water) to
be implemented if water quality does not improve;
• Where LAC is determined to be above the Level 4 trigger level, then:
o the CEO of the Office of the EPA will be informed of the exceedance and
proposed management strategies (see below) as soon as practicable and no
later than within 72 hours of detection of the exceedance (i.e. subsequent to
processing of LAC data);
o if applicable, any management actions already implemented within 72 hours
shall also be reported; and
o all management strategies will be implemented as soon as practicable.
• Coral or seagrass monitoring in the region of the water quality exceedance shall
commence within 2 weeks of the exceedance, as described in the DSDMP (Fremantle
Ports 2009); and,
• Subsequent management measures shall be in accordance with the seagrass and/or
coral health contingency monitoring and management plan described in the DSDMP
(Fremantle Ports 2009).
Toxicants within Inner Harbour Dredge Plume
Frequency
• Baseline prior to dredging, then weekly for the duration of dredging of the 300,000 m 3
potentially contaminated sediment within the Inner Harbour and then one sampling
occasion one week after dredging of the potentially contaminated sediment.
Location
Four ‘dynamic transect’ sites within the Inner Harbour dredge plume (at distances
10 m, 50m, 100 m and 500 m from dredge head) as detailed in Section 3.3,
Figure 3.1 and Figure 3.2 (N.B. ‘mock’ sites at the same distances of separation along
a transect within the Inner Harbour, at a random location overlying the footprint of
potentially contaminated sediment, shall be used for (i) baseline sampling and (ii)
water quality sampling in the week subsequent to dredging of that sediment, if the
dredge has moved out of the Inner Harbour).
Method
• Collect a single integrated-depth water sample from each location, every week.
• Store chilled and send samples to a laboratory accredited by the National Association
of Testing Authorities (NATA) for analyses of the concentration of toxicant analytes
listed in Table 4.5 (metals, organotins, OC pesticides, PAH).
• Toxicant concentration data shall be processed (within 5 days of laboratory receipt
samples) and compared against moderate protection triggers where available and
listed in Table 4.5, to determine the appropriate management response as listed
below.
Contingency Management Measures
• Where a toxicant analyte is determined to be above the trigger level, then:
o the CEO of the Office of the EPA will be informed of the exceedance and
proposed management strategies (see below) as soon as practicable and no
later than within 72 hours of detection of the exceedance (i.e. subsequent to
processing of toxicant data);
o if applicable, any management actions already implemented within 72 hours
shall also be reported; and
o all management strategies will be implemented as soon as practicable.
• The exceedance will also be noted in fortnightly reporting (by the Environmental
Monitoring Contractor) to Fremantle Ports and the Office of the EPA;
Oceanica: Fremantle Ports: Inner Harbour and Channel Deepening - Water Quality Monitoring Program 21