6. Noosa River DMP Ver0 (Combined)

                                                                Noosa River - Sediment Sampling Report
                                             BMT (OFFICIAL)



2.5 Sample Collection and Handling

Survey Vessel, Sampling Equipment and Personnel
Vibro-coring at the proposed dredge site was conducted from the specialised vibro-coring vessel
“Abyss Dive” which is owned and operated by Abyss Commercial Diving.

All sediment sampling was supervised and managed by a team of qualified BMT marine scientists and
technicians with experience in the implementation of sediment sampling and analysis programs.

Sampling Procedure
Core samples were collected using specialised pneumatic vibro-coring apparatus owned and operated
by Abyss Commercial Diving. A 40 mm core barrel was used for penetrating the sediment. Two cores
were collected at each sample site to ensure that sufficient material was retained from each site for the
analyses outlined in Section 2.5. The acceptability of each sediment core was determined immediately
following collection based on assessment of the core and discussions between the vessel crew and the
supervising scientist. The criteria for acceptance of the core included:

•   No obvious loss of surficial sediment.
•   The core must have entered the profile vertically.
•   There must be no gaps in the stratigraphy.
•   There must be no disturbance of the sediment stratigraphy.
•   The core must reach the required depth (0.5 m below dredge depth), or core refusal in clay, dense
    sand or rock.

Survey Vessel and Equipment House-Keeping
The survey vessel was thoroughly inspected and washed down prior to the beginning of sediment
sampling each day. The workspace on the vessel was washed down regularly with ambient seawater to
clean all surfaces and minimise the potential for dust contamination of samples. Sample processing
was undertaken away from any potential contamination sources such as engine exhausts, fuels, oils,
greases, lead weights, zinc anodes, antifouling paint etc.

Sampling apparatus and sample processing equipment was thoroughly cleaned with De-con 90 solution
prior to use and cleaned and rinsed with seawater between samples to prevent cross contamination
between samples.

Sample Collection, Handling and Storage
Photographs of the samples were taken and samples were logged for their physical characteristics and
variations in sediment type and texture (Annex B and Annex C). The samples from each
location/horizon were carefully homogenized in a clean container prior to the filling of clean sampling
jars supplied from the analytical laboratory.

Nitrile gloves were worn by all field personnel handling the sediment, and gloves were disposed of after
processing of each sample.

Sample bottles were labelled with a waterproof marker pen on the bottle label and lid. Sample bottles
for organic analyses were filled with zero headspace to minimise volatilisation. A field trip blank sample
container filled with clean chromatographic sand was included in the analysis for each day of sampling.




A10342 | 005 | 01                                   12                                         14 April 2022