Environmental Monitoring &
Technology
Certificate 4 - Trainee Learner Resource
Environmental Fieldwork
Study Module 4 - Sampling
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Environmental Fieldwork
Study Module 4
Assessment details
Purpose
This subject covers the ability to site and set up basic ‘ground level’ meteorological
equipment and collect and record reliable data. It also includes the ability to assess data
quality, interpret significant data features and use the data to ensure the validity of air and
noise monitoring measurements.
Instructions
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Read the theory section to understand the topic.
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Complete the Student Declaration below prior to starting.
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Attempt to answer the questions and perform any associated tasks.
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Email, phone, book appointment or otherwise ask your teacher for help if required.
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When completed, submit task by email using rules found on last page.
Student declaration
I have read, agree to comply with and declare that;
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I know how to get assistance from my assessor if needed…
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I have read and understood the SAG for this subject/unit…
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I know the due date for this assessment task…
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I understand how to complete this assessment task…
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I understand how this assessment task is weighted…
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I declare that this work, when submitted, is my own…
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Details
Student name
Type your name here
Assessor
Marker’s use only
Class code
EF
Assessment name
SM4
Due Date
Total Marks Available
46
Marks Gained
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Final Mark (%)
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Marker’s Initials
Marker’s use only
Date Marked
Click here to enter a date.
Weighting
This assessment contributes 5% to the overall mark for this subject
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Sampling
What is ‘sampling’?
A sample is formally defined as;
“A portion, piece, or segment that is representative of a whole”
It is important to remember the ‘representative’ part. This ultimately relates to the field of
statistics, but the practical outcome is that if the sample is not taken to represent the whole
body of water (in that specific space and time) then you have wasted your efforts and the
data generated from the sample will be potentially meaningless.
Sample collection methods
The two main types of sample collected by the environmental field technician are the grab
sample and the composite sample, but ultimately there are many more types of sampling
that can be employed.
Grab samples
Grab samples are the most common type of sample collected. They are taken at a particular
time and location and represent the composition of the location at the time of collection
only.
Figure 5.1 - Example of a grab sample
Grab samples are discrete samples which can be taken from flowing or still water
applications. Grab sampling is recommended;
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When flow is non-uniform
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value of the analyte is not constant
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Pollution incident surveys
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Sampling of unstable analyte's,
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Compliance to specific limits not related to average values
Study Module 4
A grab sample can be used on virtually any type of water but are commonly associated with
stream and lake samples, tap samples or discharges from processes.
Composite samples
Composite samples consist of a number of small aliquots, or grab samples, collected at
regular intervals and combined into a single container. In general composite samples are
collected at intervals of time for a fixed site rather than integrating different areas at a
single point in time. Composite samples provide average compositional data.
Due to instability of certain properties and compounds, composite sampling is not
recommended for analysis of acidity, alkalinity, BOD, carbon dioxide, residual chlorine,
microbiological, iodine, nitrate, nitrite, volatile organic compounds, dissolved oxygen and
pH. However, in certain cases, such as BOD, the collection of composite samples is routinely
required by regulatory agencies to monitor discharge limits.
Auto-sampling devices usually take the composite samples that are collected for laboratory
analysis with refrigeration facilities for storage of the sample. These devices are usually
configured to give a flow-proportional composite, as the flow increases so does the rate that
the auto sampler collects aliquots.
A simpler type of composite sample is the time-interval composite. In this form of
composite a fixed volume is collected at a fixed time period. The problem with this type of
sampling is that a mean for the sampling period can only be obtained if the flow remains
constant for the period of collection.
Other sample types
Periodic samples
A series of grab samples taken at specific time intervals or specific flow intervals which can
either be volume based or flow rate based. This type of monitoring is sometimes associated
with flow rate of rivers.
Continuous samples
This type of sampling is mainly associated with online monitors which can either measure
continuously, or at predetermined intervals, and is generally associated with process
monitoring.
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Series Sampling
This is a series of grab samples, measured individually taken to profile a water body, and
generally associated to still water bodies. The two main types are depth profiling (i.e. a
series of grab samples taken at specific depths at the same site) or area profiling (a series of
samples taken at the same depth, but at various locations).
Large Volume Sampling
This is where the anolyte we are trying to measure is in very small concentrations and we
need to take a large volume of sample and concentrate the anolyte to be measured. The
most common method is to filter a large volume through a filter cartridge, and then extract
the concentrated analyte. A typical example is sample drinking water for Giardia &
Cryptosporidium (up to 200 litres of water is filtered to produce a 100ml concentrated
aliquot).
Event sampling
This type of sampling can be either ‘on demand’ where a technician is called out to take
samples under specific circumstances (such as significant rain events) or they be engineered
as found with a rising stage sampler, which ‘stages’ the height of sample points in a frame so
that a sample is collected as the water rises. This type of sampler is used to monitor the
differences between ‘normal’ dry weather flows and the effect that rain events have on the
characteristics of the water.
The Toronto monitoring program uses rising stage samplers as part of a water quality study
with the University of Newcastle titled the LT Creek Project. You will see this type of
sampling when you do the practical week.
Sample collection equipment
Now that we have discussed the types of sample collection, we can look at the most
appropriate way in which to collect the sample from the sampling sites, as one method may
not necessarily suit all sites in the program. Sampling methods and equipment used for
sample collection include:
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Collection of sample by hand
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Collection by automatic sampler
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Samplers that collect and integrate samples over a given time
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Real time measurements by automatic means
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Measurements in the field taken by hand
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Remote sensing
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Field Observation
There is a range of equipment that may be used to aid in the collection of samples. Outlined
below are the main types of equipment used by the laboratory in routine sampling.
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Extension sampler
A extension sampler consists of an adjustable bracket designed to hold sample bottles
connected to an extendable handle. The sample bottle is placed in the bracket and secured.
The handle is extended to a sufficient length to reach a point where the sample is to be
collected. This techniques is used for safety reasons and in some cases to protect sample
integrity.
Figure 6.2 - Example of a boom sampler in action. From http://www.epd.gov.hk/. Accessed 20/5/13.
Depth sampler
Depth samplers are used in reservoirs, lakes and dams to take samples at specific depths.
They consist of a plastic tubular chamber with spring-loaded closeable ends. When a
messenger (weight) activates these ends, they close to seal the water in the chamber.
Figure 6.3 - Example of a depth sampler. The balls close the ends when activated. From
www.thesciencesource.com. Accessed 20/50/13.
The sampler is set so that the ends remain open to allow water to flow through the chamber
when being lowered to the appropriate depth by calibrated cable and winch. Once at the
correct depth, a messenger is attached to the cable and allowed to travel down to the
sampler. The messenger activates the closing mechanism of the sampler to seal in the
water. The sampler is retrieved and the contents emptied into a stainless steel bucket from
which subsamples are taken.
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Bailer
Bailers consist of a plastic/Teflon/Stainless steel body with a ball valve that : allows water in
when lowering through the water column, and seals when L retrieving. A cord is attached to
the top of the bailer to allow controlled lowering and retrieval.
Figure 6.4 - Examples of plastic bailers. From http://www.farrwestenv.com/. Accessed 20/5013
Bailers are used for discharging and sampling bores. It is lowered into the water and allowed
to fill (water pressure forces the ball to rise allowing the bailer to fill). The bailer is then
retrieved (pressure of the water in the bailer forces the ball into the lower opening sealing
the bailer). The water in the bailer is emptied into a bucket and the process is repeated until
sufficient water is collected to take a representative sample.
Automatic Samplers
Automatics samplers generally consist of a peristaltic pump; control mechanism,
distribution arm and sample containers. Automatic samplers are used where sampling is
required when manual sampling is' inappropriate due to cost, time constraints or other
factors. The main types of operation of automatic samplers are dependent on time, volume
or events.
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Timed sampling ignores variations in flow. Sampling has a defined start and finishing
time period. The start time for sampling can be delayed by minutes, hours or even days.
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Volume based sampling is normally triggered by a flow meter which provides a signal
to the sampler at determined flow intervals. Time intervals between flow interval!; can
be recorded on some automatic samplers so that a time vs flow analysis can be made.
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Event sampling is initiated by a change in conditions. These conditions can vary
dependant on the type of instrument connected to the sampler to provide the signal to
trigger sampling.
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Examples of event sampling may be a storm event, a change in chemical conditions such as
salinity or a change in river flows. Samples for Timed, Volume or Event sampling can be
either discrete or composite. Continuous sampling can be triggered by any of the mentioned
types of operation.
Decontamination of sampling equipment
When you take samples, the sampling equipment will become contaminated from the
analytes in the sample. The potential consequence of this is that when you collect the next
sample, cross contamination may occur, which will negatively affect the data integrity. To
avoid this all sampling equipment that is not dedicated to site must be decontaminated, and
dedicated samplers should be rinsed with the sample prior to sampling collection.
Decontamination is particularly important when collecting samples for microbiological,
organic, metals or low concentration analysis. It is also of key importance when the data
from the samples is being used for legal reasons.
Decontamination agents come in a variety of forms including;
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Chelating agents (similar to EDTA)
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Detergents
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Caustic substances
Figure 6.5 - Example of a proprietary decontamination agent. Note that this is not a recommendation,
just laziness! From www.decon.co.uk. Accessed 8/9/13.
Sample collection
Sample containers
It is important when undertaking sampling, particularly for trace analytes, that the sampling
equipment is inert, that is, it does not cause contamination or interference with the sample.
For example:
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Organics have a tendency to adsorb to plastic (including polyethylene, polypropylene
and polycarbonate). Therefore, stainless steel equipment such as buckets and sampling
rods should be used. Glass sample containers are preferred.
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When sampling for metal analytes the use of metal equipment, and some glasses
such as soda glass should be avoided. Rubber can also cause contamination when
sampling for trace concentrations. Plastic equipment should be used when possible when
analysing for metals.
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When sampling for analytes that are the major constituents of glass (eg sodium,
potassium, boron and silicon), glass equipment and containers should be avoided.
Polyethylene and borosilicate glass
These are general purpose containers are generally suitable for sampling for the
determination of physical and chemical parameters such as pH, conductivity, alkalinity, BOD
and many more.
Amber (brown) glass
When samples or analytes are light sensitive (such as algae and some organic compounds),
they must be protected from exposure to light so containers made with opaque materials or
amber glass are recommended.
Figure 6.6 - Examples of brown bottles used for sampling. From http://www.aquasample.com/ .
Accessed 8/9/13
Organic Compounds
These analytes pose many unique problems for samplers and analysts alike, and as such the
chemical behaviour, including toxicity and volatility, as well as adsorption properties and
their potential to decompose, all need to be considered when sampling.
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As nearly all plastic interferes with organic analyses through contaminants leeching from the
plastic or organic compounds dissolving into the plastic, plastic containers should be
avoided for sampling organic compounds, and replaced with glass containers.
Tests include volatile organic compounds, semi-volatiles, pesticides, PCB's and oil and
grease. The caps of sampling containers can also cause problems, particularly if they are
plastic. Caps should be glass or be lined with aluminium foil or PTFE, and some require a
‘headspace’ (a gap where volatile substances can equilibrate with the solution) to be
included whereas other require filling completely.
General Samples
These samples must be collected in a container of appropriate size, generally a 1.25L plastic
bottle. As a rule of thumb the cleaner the water, the more sample that will be required.
Tests include pH, Turbidity, EC, TSS, TOS, BOD etc. Depending on how the samples will be
analysed and other complicating factors, your bottle supplier (the laboratory) will advise
whether the sample bottles should be rinsed with the sample and whether they should be
filled to the top.
Sampling for Microbiological Analysis
Microbiological samples must be collected in the sterile bottle provided. These should
always be collected first. These bottles are sterile and will remain so as long as they are not
opened, cracked or otherwise contaminated.
Care must be taken when collecting the sample to avoid contamination. Remember that
splashing and airborne matter may also contaminate. The lid of the bottle should be held in
such a way as to reduce the risk of contaminants from fingers and airborne matter. It must
not be put, thread down on any surface.
Never rinse a sample bottle with sample prior to filling for microbiological use.
Preservative will be added to bottles used for samples that may contain chlorine which will
counteract the effects of chlorine in the sample (i.e. killing the micro-organisms). Samples
must be taken in such a way as to reduce contamination. The bottle must not be filled
completely; approximately one inch of airspace should be left (to allow the microorganisms
to ‘breathe’. It should be capped as soon as the sample is taken.
Sampling for Metals
Total Metals (All metals except mercury)
Samples for total metals should be collected in 200mL plastic bottles provided. Sample
bottles contain ultra-pure nitric acid as a preservative. Glass bottles need not be used, and
some metals may be affected by storage in glass. For mercury samples it is preferable to
collect the sample in glass, as mercury can infuse & or defuse through plastic.
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Dissolved Metals (All metals except mercury) .
Samples for dissolved metals should be collected and filtered through a 0.45um filter into
50mL bottles supplied. Sample bottles contain ultra-pure nitric acid as a preservative. Both
the syringe and filter must be rinsed with sample before filling the bottle. Alternatively
dissolved metals may be sub-sampled upon receipt into the laboratory, but it must be
realised that some metals may come out of solutions over time and it is not possible to
reproduce the same circumstances as at the time of sampling. If filtering on site is not
possible, then the sample must not be preserved.
Sampling for Nutrients
Total Nutrients
Samples for total nutrients should be collected in 50mL plastic bottles. Samples do not need
to be frozen, but should be stored at 4'C. Samples can be stored for a week prior to analysis.
Filterable Nutrients (Nitrate, Nitrite, Ammonia and ortho-Phosphate)
Samples for filterable nutrients should be filtered immediately after collection through
0.45um filters into 15mL tubes provided.
The syringe, filter and tube should all be rinsed with sample, before filling the tube. Samples
should be frozen after collection, they then could be stored frozen for up to a month prior
to analysis.
Sampling for general organic materials
Total Organic Carbon
Samples for total organic carbon should be collected in 50mL plastic containers. Samples
should be stored at 4'C after collection. Samples should be analysed within 24 hours.
Sampling for Oil and Grease
Samples for oil and grease must be collected in glass containers, normally with a wide
mouth to allow for quick filling. It is important to collect the sample in one motion, and
avoid skimming the surface as this will tend to bias the result. Plastic must not be used as
plasticisers may leech from the container, or oil and grease may have a preference for the
plastic of the container, either of which could affect the results.
Sampling for Total Petroleum Hydrocarbons - Fractionated
Samples for fractionated total petroleum hydrocarbons must be collected in a 1 L amber
glass container and a 40mL glass vial provided. The vial must be filled completely to exclude
all air and the plastic septum in the vial lid must be placed so that the Teflon lining is facing
towards the sample. Plastic must not be used as plasticisers may leech from the container
and affect the results. Samples need to be kept cool and in the dark.
Sampling for Methylene Blue Active Substances (Detergents)
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Samples for methylene blue active substances must be collected in clean 250mL plastic
bottles. Leave sufficient air space to allow for expansion. Samples should preferably be
frozen after collection.
Sampling specific for organic compounds
Pesticides, PAH's and PCB's Samples
These must be collected in 1 L amber glass bottles with Teflon or aluminium lined caps
provided. The volume of sample collected is dependent upon the detection limit required.
The bottles provided have been thoroughly cleaned and solvent rinsed. Plastic bottles must
not be used because some compounds can be absorbed into the plastic as well as
plasticisers leaching out, which will lead to incorrect results.
Trihalomethanes
Samples for Trihalomethanes must be collected in 40mL Head Space Vials with a Teflon
lined septum cap. The bottle must be filled to the top, ensuring all air excluded from the
bottle before capping.
Volatile Organic Compounds
Samples for volatile organic compounds must be collected in the 40mL glass vials provided.
The vials must be completely filled to exclude all air. The plastic septum in the lid of the vial
must be positioned so the Teflon lining is facing the sample.
Sampling for Phenolics
Samples for total phenolics must be collected in 100mL glass bottles.
Sampling for non-metal inorganics
Sampling for Cyanides
Samples for cyanide may be collected in either 100mL plastic or glass bottles.
Sampling for Sulfite
Samples for sulfite must be collected in the 100mL bottles provided. These bottles contain a
preservative of EDTA solution and must not be rinsed with sample prior to collection.
Sampling for Sulfide
Samples for sulfide must be collected in the 100mL bottles provided. These bottles contain a
preservative of zinc acetate solution and must not be rinsed with sample prior to collection.
Algae
Samples for algal Identification and counts should be collected in plastic bottles- 200ml 500ml. If samples cannot be delivered within 24 hours, it is recommended that Lugol's
solution (iodine stain) be added to samples to preserve them.
Chlorophyll
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Samples need to be kept cool and submitted within 24 hours. If this is not possible, sample
should be filtered through a glass filter paper, the paper then being wrap in Alfoil and
frozen. They can be stored for up to a month whilst frozen. It is critical that the volume
filtered is recorded and submitted with the filter paper.
Where to get sample bottle information
Most of the time, the sample bottle type, volume and filling behaviour (i.e. leaving a head
space or not) will be instructed to you by the laboratory that supplies the bottles (see figure
below). Other than that, you can obtain generic information from Australian Standards and
the APHA Standard Methods for Water and Wastewater (see bibliography).
Figure 6.7 - An example of sample collection information from a laboratory (ALS).
Sample collection techniques
Grab sample methodology
Hold bottle near its base and plunge it, neck downward, below the surface. Tum bottle until
the neck points slightly upward and the mouth is directed towards the current. If there is no
current, as is the case of a reservoir, create a current artificially by pushing bottle forward
horizontally in a direction away from the hand.
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Fill the container with enough sample to rinse it, cap and shake. Empty the rinse
water away from the immediate site of sampling - downstream if possible. Take the
sample, cap and store on ice.
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If taking samples from a flowing stream from a standing position, or from a boat,
collection should be performed facing upstream.
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If sampling in very shallow water use a jug, or similar container to collect sample,
carefully avoiding disturbing the bottom. In flowing water, rest the base of the jug on the
bottom, with the lip angled slightly upwards to allow the water to flow into the jug with
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minimal disturbance of the bottom. Make sure the jug is clean, rinsed at the site, and the
sample well mixed prior to decanting into the sample bottles.
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For marine and lake sampling, a boat should be used if possible, to avoid 'edge
effects' in sampling from the shore. Collection should be from the bow with the boat
facing against the direction of the water movement, if this is discernible. Ideally, the
sampling site should be approached from downstream, down current or against the tide.
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In still water, collect the sample away from the direction of approach.
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'Surface' samples should ideally be taken from 30 centimetres below the surface,
unless the intention is to bias the sample with surface film.
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'Bottom' samples should ideally be taken one metre above the bed to avoid
sediment contamination. A conscious attempt should be made to avoid disturbance of
the bed during approach.
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Fill containers completely with sample unless otherwise advised.
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Ensure that the chain of custody is fully documented. This means that the person
responsible for each step in the sampling process is recorded.
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A field record of unusual meteorological, tidal or hydrological conditions; particular
difficulties encountered during sampling; unexpected delays or other departures from
normal circumstances should be made for possible later evaluation, together with the
original records of any field measurement devices.
Composite sample methodology
If samples were to be collected in duplicate or triplicate each bottle would ideally have the
same composition. In order to achieve this, the sample should be collected in a large
container, mixed and split into appropriate containers.
The simplest and easiest way to ensure all sets have a similar composition would be to use
an open-mouthed jug to collect the sample from the source and pour it into a 5 - 10 litre
container. The combined sample should be mixed thoroughly and immediately transferred
into the appropriate sample containers.
However this method is not appropriate for certain analysis such as microbiological analysis,
oil and grease, fractionated hydrocarbons, and volatile organics, these should be collected
directly from the source using the appropriate containers.
Sealing containers
The simplest way to seal a container is to use tape, however it must not be easily removed
and replaced. To overcome this, the tape needs to be wrapped around the lid of the
container so a tight seal is formed, and signed by the authorised officer at the join, so any
tampering can be easily recognised. It is strongly recommended that bottles known to be
new, or bottles supplied by a registered NATA laboratory be used for sample collection.
Sample identification
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Thorough chain of custody procedures need to be carried out, especially for regulated
sampling. There are several parts to the chain of custody procedures including sample
labels, field logbook, chain of custody record, sample submission forms and sample delivery.
Labelling
When samples are collected it is vital that they are labelled correctly, to prevent
misidentification. Labels should include the following information:
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sample name
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sample number
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name of sampler
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date and time of collection
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place of collection
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preservative used
It is important to ensure that the labels remain on the containers even if they are wet, and
that waterproof ink is used so the information can be easily read.
Field logbooks should also be kept as a record of the sampling that took place. There should
be enough information in the logbook to ensure that the sampling event can be clearly
reconstructed for legal reasons The logbook should be protected and kept in a safe place. It
should contain the following information:
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purpose of sampling
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location of sampling point
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name and address of field contact
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producer of material being sampled and address (it different trom the location)
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type of sample
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method of preservation
Chain of custody
A chain of custody record should be included with every batch of samples. The record
should include the following information:
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sample identification
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signature of collector
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date, time and address of collection
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sample type
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signatures of persons involved in chain of possession
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inclusive dates of possession
Sample submission forms also need to be included with every batch of samples. This may be
combined with the chain of custody record. This is filled out by both the sampler, and signed
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by the laboratory personnel. The sampler should include the most important information
from the field logbook for example;
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sample identification
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sample type
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date and time of collection
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method of preservation
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analysis to be performed
The laboratory personnel should complete the form with the following information:
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the name of the person receiving the sample
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laboratory sample number
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date of sample receipt
Filtration
There are a few analyses that need filtered samples, including nutrients and dissolved
metals and it is preferred that these samples be filtered in the field, particularly for nutrients
as bacteria can change the proportions of nitrogenous compounds within the sample.
Figure 6.8 - Example of field filtering equipment. From http://www.envcoglobal.com/. Accesses 8/9/13
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Samples to be analysed for dissolved metals should also be filtered in the field, and the
acidified to prevent metals dropping out of solution. Anions can also be filtered in the field,
however it is not critical and can be done on receipt into the laboratory.
If both total and dissolved metals are required and only one bottle has been provided, the
sample must not be filtered; any preservative must be rinsed out prior to filling the bottle.
In this case a portion of the sample will be filtered upon receipt to the laboratory. It is
particularly important to have clear labels indicating that the sample has been filtered.
The process of filtration depends upon the equipment you have, and can be as simple as a
filter connected to a syringe or involve vacuum pumps and other laboratory equipment. The
equipment you have usually depends upon the amount of sampling you need to do as it can
be quite a time consuming process.
Sample preservation, transportation and storage
Preservation
Waters, waste waters, bottom sediments and sludges are susceptible to change to differing
extents as a result of physical, chemical and biological reactions which may take place
between the time of sampling and the analysis, The nature and rate of these changes are
often such that, if the necessary precautions are not taken during the sampling, transport
and storage, the concentrations determined will be different from those-existing at the time
of collection.
It must be emphasised that these changes are often sufficiently rapid to modify the sample
considerably in the space of several hours. Certain constituents should be measured in the
field to obtain accurate results, such as temperature, dissolved oxygen, free and residual
chlorine, It should be stressed that, if there is any doubt, the analyst should be consulted
before deciding on the precise method of handling and transportation.
As a general rule samples are not preserved in the field other than packing the samples on
ice/ice bricks, and keeping them in the dark. It is preferable to use ice bricks or gel packs as
ice melts and is a potential source of contamination if samples are not kept upright in eskies
and bottle caps are not put on securely.
It should be emphasised that refrigeration or freezing of the sample is only truly effective if
it is applied immediately after the collection of samples.
There are some analyses that do need to be preserved in the field; this includes metals,
Trihalomethanes and microbiological samples, In these cases, the preservative has already
been added to the sample container, and therefore the container cannot be rinsed with the
sample before filling.
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Storage
Samples should be stored on ice bricks in darkness (i.e. in eskies or other suitable
containers), or in refrigerators while waiting to be transported to the laboratory. Sample
containers should be kept upright at all times, and firmly sealed. Samples to be transported
should be packed carefully to protect the containers from damage and protect samples
from contamination.
Samples should be kept upright during transportation, and should be packed in such a way
as to minimise the occurrence of falling over. Containers that have fallen over in eskies
containing melted ice leaking sample may be subject to contamination, this is particularly
important in the case of microbiological samples.
Glass bottles should be packed in such a way as to minimise breakage. This may include
wrapping sealed bottles in bubble wrap, or placing packaging between bottles to cushion
them against impact.
Transportation
It is preferable that the samples be transported as soon as possible to the laboratory, since
many tests have a finite time in which they should be completed. Ideally samples will be
transported on the same day as collection, however this is not possible in many cases.
Microbiological samples should be delivered to the laboratory within 6 hours and no later
than 24 hours.
There are that many possibilities associated with individual sampling storage and
transportation requirements. These will be driven by your workplace procedures, the client
needs, the sample requirements and the distance between the sample location and the
required laboratory.
The use of blanks
With any sampling regime there will always be a requirement for the use of blanks. These
are discussed in detail in a later module on quality assurance and control
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Assessment Task
After reading the theory above, answer the questions below. Note that;
◗
Marks are allocated to each question.
◗
Keep answers to short paragraphs only, no essays.
◗
Make sure you have access to the references (last page)
◗
If a question is not referenced, use the supplied notes for answers
Answer the following questions
1. It is very important for a sample to be representative of the whole body of water it
comes from. From a legal viewpoint, what are the potential consequences of obtaining
an unrepresentative sample? 3 mk
Type your answer here
Leave blank for assessor feedback
2. A composite sample is designed to give a more representative picture of a type of water.
What then are the benefits of providing ‘grab’ samples? 4 mk
Type your answer here
Leave blank for assessor feedback
3. Under what circumstances are large volume samples required? 2 mk
Type you answer here
Leave blank for assessor feedback
4. In terms of costs (both financial and time), what are the potential consequences of not
using checklists when preparing to sample? 3 mk
Type your answer here
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Leave blank for assessor feedback
5. Explain what equipment you might use to sample under the following scenario’s. 6 mk
a. A multipoint grid sample of a lake looking at algae in surface water?
Type your answer here
Leave blank for assessor feedback
b. Sampling points along a small creek looking and general indicators of pollution?
Type your answer here
Leave blank for assessor feedback
c. Depth profile study of sediment loads in a lake?
Type your answer here
Leave blank for assessor feedback
6. Identify some potential consequences of not decontaminating equipment between each
sampling event. In your answer be sure to address both legal and financial consequences
for the client. 4 mk
Type your answer here
Leave blank for assessor feedback
7. Why is ensuring a sample is placed in the correct type of bottle important? Provide three
examples of how analytes in the sample can be affected by the an incorrect bottle they
are stored in. 5 mk
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Type your answer here
Leave blank for assessor feedback
8. Identify two analytes that (may) require field filtering. 2 mk
Type your answer here
Leave blank for assessor feedback
9. Explain how filtering a sample to be used for metals analysis helps differentiate between
total and dissolved metals? What would be the analytical consequence of acidifying the
sample prior to filtering? 6 mk
Type your answer here
Leave blank for assessor feedback
10. Sometimes you might collect a large sample in a bucket or jug, and then fill individual
bottle from that. When is it not appropriate to use this method? 3 mk
Type your answer here
Leave blank for assessor feedback
11. Briefly outline the ‘rules’ for collecting samples from which microbiological information
is to be gained? 5 mk
Type your answer here
Leave blank for assessor feedback
12. List the key information that a sample label should have? 5 mk
Type your answer here
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Leave blank for assessor feedback
13. What is a ‘chain of custody’ form? In your answer, address information relating to the
types of monitoring program they are typically used in, as well as their key function and
the potential consequences of not using one correctly or at all. 10 mk
Type your answer here
Leave blank for assessor feedback
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Assessment Submission
Answers
◗
Attempt all questions and tasks
◗
Type your answer into the text fields provided.
Submission
Use the documents ‘Save As…’ function to save the document to your computer using the
file name format of;
name-classcode-assessmentname
Note that class code and assessment code are on Page 1 of this document.
◗
email the document back to your teacher
Penalties
If this assessment task is received greater than seven (7) days after the due date (located on
the cover page), it may not be considered for marking without justification.
Results
Your submitted work will be returned to you within 3 weeks of submission by email fully
graded with feedback.
You have the right to appeal your results within 3 weeks of receipt of the marked work.
Problems?
If you are having study related or technical problems with this document, make sure you
contact your assessor at the earliest convenience to get the problem resolved. The name of
your assessor is located on Page 1, and the contact details can be found at;
www.cffet.net/env/contacts
References
Note that some of these resources might be available from your teacher or library
Bates, G. (2010). Environmental Law in Australia. Australia: LexisNexis-Butterworths.
Bratram, J. E. (1996). Water Quality Monitoring - A Practical Guide to the Design and
Implementation of Freshwater Quality Studies and Monitoring Programmes. New
York?: UNEP/WHO.
Burden, F. E. (2002). Environmental Monitoring Handbook. McGraw-Hill Professional.
CFFET. (2012). Practical Laboratory Skills - supplementary results sheet. Newcastle: Hunter
TAFE.
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EPA, N. (1996). Environmental Guidelines: Solid Waste Lanfills. Chatswood: Environmental
Protection Authority.
EPA, S. (2007). EPA Guidelines: Regulatory monitoring and testing - water and wastewater
sampling. Adelaide: Environment Protection Authority (South Australia).
ESDSC. (1992). National Strategy for Ecologically Sustainable Development. Canberra:
Department of Sustainability, Environment, Water, Populations and Communities.
Ferrier, R. C. (2010). Handbook of Catchment Management. Oxford: Wiley-Blackwell.
Hauer, F. R. (2007). Methods in Stream Ecology, 2nd Ed. Burlington: Academic Press.
Jorgensen, S. E. (2005). Handbook of Ecological Indicators for Assessment of Ecosystem
Health. Boca Raton: CRC Press.
Manahan, S. (2000). Environmental Chemistry. Boca Raton: Lewis Publishers.
Newton, A. (2007). Forest Ecology and Conservation. Oxford: Oxford University Press.
StandardsAustralia. (2004). AS/NZS ISO 14001:2004 Environmental Management Systems:
Requirements with guidance for use. Australia: Standards Australia.
U.S.GeologicalSurvey. (Variously dated). National field manual for the collection of water
quality data: U.S. Geological Survey Techniques of Water Resources Investigation,
book 9, chaps. A1-A9. available online at http://pubs.water.usgs.gov/twri9A.
vanLoon, G. W. (2011). Environmental Chemistry: a global perspective. New York: Oxford
University Press.
Vogel, A. (1987). Vogel's textbook of quantitative inorganic analysis, 4th Ed. London:
Longman Group Limited.
Workplace Health and Safety Act 2011. (n.d.).
Workplace Health and Safety Regulation 2011. (n.d.).
Other resources
If they exist, the items listed below are for general information only. If you know of a good
resource that other students might find useful let your teacher know and we shall add it to
the list.
http://www.epa.gov/QUALITY/dqos.html
Where to get help
Contact your teacher if you run into any trouble this unit. You would be surprised how
flexible we are at accommodating your needs, but communication is the key. If you don’t let
us know you are having trouble, we may have trouble trying to help you.
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