Gosford City Council Historical Water Quality Review & Analysis

FUTURE DIRECTIONS FOR WATER QUALITY / ENVIRONMENTAL HEALTH MONITORING 4-9
used for sampling of surface waters include bottle samplers, pumping systems, depth samplers,
automatic samplers and integrated samplers. Groundwater sampling utilisers a number of pumping
methods. Sediments are often sampled to determine the composition and concentration of
contaminants, as well as the number of organisms. Sediments are typically sampled using a range of
dredge, grab and coring methods. The choice of sampling method will depend on the parameter and
conditions being measured. All methods and equipments are required to meet relevant Australian or
ISO standards.
A number of parameters can only be accurately measured in the field (eg temperature, flow), whilst
others are susceptible to change in the sample after collection (eg dissolved oxygen, pH).
Consideration should be given at this stage to utilising highly reliable sensors that are capable of
accurately recording these types of parameters in the field.
The sample containers are selected to minimise the potential for adsorption or contamination of the
sample. Glass and plastic containers each have potential limitations and methods to consider for
preparing the containers for sampling.
Particular care is required with sampling protocols to prevent contamination of the samples by dust,
powder, skin and hair. Care is particularly required when boats and helicopters are used to assist with
sampling to ensure that these forms of transport do not lead to contamination of the samples.
Observations and characteristics of the site should also be recorded at the time of sampling, and
recorded on a standardised field sheet. A quality assurance/control system is required for field
sampling to control sampling errors and manage the samples following collection. Field staff will
need to be trained and be competent at undertaking the sampling tasks. The hazards likely to be
encountered by the sampling staff will need to be identified and addressed to ensure that these
hazards are minimised.
4.3.5 Laboratory Analysis
The objective of the laboratory analysis is to obtain accurate and precise data in a safe environment.
The recommended methodology for laboratory analysis is summarised in Figure 4.8.
Figure 4.8 Framework for Laboratory Analysis (ANZECC/ARMCANZ, 2000)
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