ISO 5667-12:1995

INTERNATIONAL ISO
STANDARD 566742
First edition
1995-12-01
Water quality - Sampling L
Part 12:
Guidance on sampling of bottom Sediments
Qualit6 de l’eau - ~chantillonnage -
Partie 72: Guide g&Wal pour l’&hantjllonnage des Sediments
Reference number
ISO 5667-12:1995(E)

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ISO 5667=12:1995(E)
Contents
Page
1
1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Normative references . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
3 Definitions . . . . . . . . . . . . . . . . .~. 1
4 Sampling equipment . 2
5 Sampling procedure . 6
6 Composite samples . . . . . . . . . .*.*. 8
7 Storage, transport and stabilization of samples . 9
8 Safety . IO
9 Statistical considerations of sampling . IO
IO Sample identification and records . IO
Annexes
A Description of the scissor-grab System (van Veenhapper type) 12
B Description of the Piston drill System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
C Description of the corer System involving a diver . . . . . . . . . . . . . . . . . 16
D Description of the Beeker Sampler System . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
E Description of the sealed core Sampler System . 20
F Description of the wedge core or Vrijwit drill System . 22
G Description of the falling bomb System . . . . . . .*. 24
H Description of the Jenkins mud Sampler System
. . . . . . . . . . . . . . . . . 26
J Description of the Craib corer System .
28
K Description of a Piston corer . 30
L Description of peat borers . 32
M Bibliography . 34
0 ISO 1995
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronie or mechanical, including photocopying and
microfilm, without Permission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-I 211 Geneve 20 l Switzerland
Printed in Switzerland

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0 ISO
ISO 5667=12:1995(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide
federation of national Standards bodies (ISO member bodies). The work
of preparing International Standards is normally carried out through ISO
technical committees. Esch member body interested in a subject for
which a technical committee has been established has the right to be
represented on that committee. International organizations, governmental
and non-governmental, in liaison with ISO, also take patt in the work. ISO
collaborates closely with the International Elsctrotechnical Commission
(IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 5667-12 was prepared by Technical Committee
ISO/TC 147, Water quality, Subcommittee SC 6, Sampling (general
methods).
ISO 5667 consists of the following Parts, under the general title Water
quality - Sampling:
- Part 1: Guidance on the design of sampling Programmes
- Part 2: Guidance on sampling techniques
- Part 3: Guidance on the preservation and handling of samples
- Part 4: Guidance on sampling from lakes, natura/ and man-made
- Part 5: Guidance on sampling of drin king water and water used for
food and beverage processing
- Part 6: Guidance on sampling of rivers and streams
- Part 7: Guidance on sampling of water and steam in boiler plants
- Part 8: Guidance on the sampling of wet deposition
- Part 9: Guidance on sampling from marine waters
- Part IO: Guidance on sampling of waste waters
- Part 11: Guidance on sampling of groundwaters
- Part 12: Guidance on sampling of bottom Sediments
of
- Part 13: Guidance on sampling sewage, wa terworks and rela ted
sludges
. . .
Ill

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0 ISO
ISO 5667=12:1995(E)
- Part 14: Guidance on monitoring the quality of sampling procedures
- Part 15: Guidance on the preservation and handling of sludge and
sedimen t samples
- Part 16: Sampling and pretrea tmen t of samples for bio testing
Annexes A, B, C, D, E, F, G, H, J, K, L and M of this part of ISO 5667 are
for information only.

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0 ISO ISO 5667=12:1995(E)
Introduction
This part of ISO 5667 should be read in conjunction with ISO 5667-1,
ISO 5667-2 and ISO 5667-3.
The general terminology used is in accordance with the various Parts of
ISO 6107, and more particularly, with the terminology on sampling given
in ISO 6107-2.

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onal ly left blank

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ISO 5667=12:1995(E)
INTERNATIONAL STANDARD 0 ISO
Sampling -
Water quality -
Part 12:
Guidance on sampling of bottom Sediments
possibility of applying the most recent editions of the
1 Scope
Standards indicated below. Members of IEC and ISO
maintain registers of currently valid International
This patt of ISO 5667 provides guidance on the sam-
Standards.
pling of sedimentary materials from
ISO 2602:1980, Statistical interpretation of test re-
- inland rivers and streams;
sults - Estimation of the mean - Confidence
in terval.
- lakes and similar standing bodies; and
ISO 2854:1976, Statistical interpretation of data -
- estuarine and harbour areas.
Techniques of estimation and tests rela ting to means
Industrial and sewage works sludges, palaeo-
and variances.
Iimnology sampling and open ocean Sediments are
specifically excluded although some techniques may
ISO 5667-1: 1980, Water quality - Sampling -
apply to these situations. Sampling specifically for the Part 7: Guidance on the design of sampling pro-
measurement of rates of deposition, other transport grammes.
criteria and detailed strata delineation is not within the
ISO 5667-3:1994, Water quality - Sampling -
scope of this part of ISO 5667.
Part 3: Guidance on the preservation and handling of
The investigation may have the following objectives:
samples.
- the descriptive mapping of an area;
ISO 9391 :1993, Water quality - Sampling in deep
waters for macro-invertebrates - Guidance on the
- the monitoring at regular intervals of fixed markers
use of colonization, qualitative and quantitative sam-
such as buoys;
plers.
- examining the quality of dredger spoil; and
ISO 10381-6: 1993, Soil quality - Sampling -
Part 6: Guidance on the collection, handling and stor-
- fundamental research.
age of soil for the assessment of aerobic microbial
processes in the laboratory.
2 Normative references
3 Definitions
The following Standards contain provisions which,
For the purposes of this patt of ISO 5667, the follow-
through reference in this text, constitute provisions
ing definitions apply.
of this part of ISO 5667. At the time of publication, the
editions indicated were valid. All Standards are subject
3.1 composite Sample: Two or more samples or
to revision, and Parties to agreements based on this
part of ISO 5667 are encouraged to investigate the subsamples mixed together in appropriate known
1

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0 ISO
ISO 5667=12:1995(E)
laboratory. For guidance on the cleaning of Sample
proportions, from which the average result of a de-
Containers, reference should be made to ISO 5667-3.
signed characteristic may be obtained. The individual
In all cases, consultation with the receiving laboratory
portions may be derived from the same stratum or at
should be regarded as mandatory practice.
the Same Sediment thickness. The Sample com-
ponents are taken and pretreated with the same
equipment and under the same conditions.
4.2 Criteria for selection of apparatus
3.2 pile-working: The phenomenon which occurs
4.21 Type of investigation
when the Sample rising up the inside of a Piston corer
meets a resistance due to its own friction, a blockage
Three types of investigation tan be distinguished:
by a large piece of stone, or the tube being full.
Chemical investigation;
a)
3.3 descriptive mapping: A description of the
Sediment present, in terms of its nature, Variation and
physical investigation; and
b)
extent. The exercise is carried out by precise marking
of Sample locations and recording of site conditions.
c) biological investigation exclusive of colonization
Pre-established conditions may be a requirement of
Samplers, traps or nets.
the exercise.
When a grab System (4.3.1) is not used, the criteria
3.4 monitoring: Establishment of Variation with
for selection of sampling apparatus may also be re-
time of the physico-Chemical and descriptive charac-
quired to meet the following conditions:
teristics of the Sediment.
- storage of the Sediment without changing the
3.5 quality of dredger spoil: To establish the
stratigraphy;
Chemical nature and, in the case of Sandbank dredg-
ing, the physical properties of the Sediment layer re-
- allow the selection of a layer; and
moved by the dredging process and disposed of
off-site. - allow sampling at the required water depth.
4.2.1 .l Chemical investigation
4 Sampling equipment
In this type of investigation, the nature and amounts
4.1 Sampling Container materials and types
of the substances which have become bonded to the
Sediment may be determined. Some Chemical spe-
Polyethylene, polypropylene, polycarbonate and glass
cies bond in preference to small mineral particles and
Containers are recommended for most sampling situ-
organic matter while some are incorporated in residual
ations, although glass jars have the advantage that the
pore water. lt should be noted that where the sam-
condition of their internal surface is more readily ap-
pling device is made of metal then abrasion and
parent and they tan be sterilized more easily than
Chemical action, for example from sulfides and phos-
most plastics materials Prior to use in microbiological
phates, may lead to specific contamination. Appropri-
sampling situations.
ate quality control measures should be undertaken in
full consultation with the receiving laboratory in Order
Glass Containers should also be used when organic
to establish the degree of influence of such effects
constituents are to be determined, whereas poly-
on the Survey results. Some study Parameters may
ethylene Containers are preferable for sampling those
require to be maintained in an Oxygen-free atmos-
elements that are major constituents of glass (e.g.
phere (e.g. sulfides) and storage and handling under
sodium, potassium, boron and Silicon) and for sam-
pressure of an inert gas may be needed. In all cases
pling of trace metallic moieties (e.g. mercury). These
analysis should be performed as quickly as possible.
Containers should only be used if preliminary tests in-
dicate acceptable Ievels of contamination.
4.2.1.2 Physical investigation
If glass Containers are used for storing Sediments with
In this type of investigation the structure, texture and
pore waters which are weakly buffered, borosilicate
layer formation of the water bed are determined.
rather than soda glass Containers should be Chosen.
These details are particularly important for Sand, clay
and Shell production and for geographical, morpho-
Reference should always be made to both the stan-
logical and, in some cases, geotechnical investi-
dard analytical procedure for detailed guidance on the
gations.
type of Sample Container to be used and the receiving
2

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0 ISO ISO 5667=12:1995(E)
4.3.1.2.3 Accuracy of Sample
4.2.1.3 Biological investigation
A Sample taken with a scissor grab will always be
A biological investigation generally involves classifying
disturbed. Inaccuracies arise because of washing
the species and numbers of flora and/or fauna present
on and in the Sediment bed. In nearly all cases sam- away of the fine fractions. The depth of Penetration
pling is carried out in the habitat layer. The probe is unknown and dependent on the nature of the bed
depth is generally a maximum of 50 cm. For specific for any particular instrument, for example, the grab
tan sink through a thin silt layer so that it will not be
details, reference should be made to ISO 9391 for
known at what depth the Sample has been taken from
methods involving colonization traps or net sampling.
within the bottom Sediment.
In some cases microbiological action may also be of
interest, such as denitrification, Phosphate release,
methylization of metals such as mercury or tin.
4.3.1.2.4 Nautical conditions
The scissor grab tan be used in both shallow and
4.3 Types of apparatus
deep water and in areas of slow and fast currents.
NOTE 1 Additional equipment, which emulates or com-
However, the construction and mass need to be
pliments the advantages of that discussed in this part of
adapted to suit the conditions. lt is recommended that
ISO 5667, may also be available commercially. The scope
trials using objects of a similar mass be carried out;
for inclusion in future revisions will be considered at the
this indicates whether strong currents affect the pos-
appropriate time.
ition of the samples. Additional weights tan then be
added if it is found necessary. lt is recommended that
4.3.1 Grab Systems
a secondary line carrying a marker float be attached
as a security measure, in case the main line has to
be abandoned for safety reasons. This will aid recov-
4.3.1 .l General
ev.
Many samples are collected using bed grabbers. The
most weil-known is the scissor-grab, sometimes
4.3.2 Corer Systems
known as the van Veenhapper type. There are, how-
ever, a large number of variations. In general, grab
Sampling using a corer System depends on the prin-
Systems consist of one or more hinged buckets which
ciple of driving a hollow tube into the bed so that the
close whilst being raised. During closing, Sediment is
Sediment is pushed into it. A Sample is obtained by
enclosed by the buckets providing disturbed samples.
pulling the tube out of the bed. This sampling principle
Probe depths vary from 5 cm to 50 cm, depending
is used in many different ways. lt is possible to dis-
upon the size and mass of the Sampler and the
tinguish between Systems in which the tube, where
structure of the bed material. Due to the grab con-
necessary extended by rods, is pushed into a bed
struction, there is a large Chance of losing part of the
manually and Systems in which the tube is inserted
finer fraction and/or the top layer. Grabs are available
by means of its weight or a Vibration mechanism.
in a variety of designs. Since all grab Systems have
the Same sampling characteristics, only the van
Veenhapper type is described in detail in annex A. In
4.3.2.1 Application
general, detailed operating instructions are provided
by the manufacturer.
The Systems described are recommended for physi-
cal, Chemical and limited biological investigations.
4.3.1.2 Scissor grab or clam-Shell buckets
4.3.2.2 Type of bed
4.3.1.2.1 Application
Some sandy beds may be suitable but trials will need
The System is recommended for physical, Chemical
to be undertaken first. Clay types and soft peaty ma-
and biological investigations.
terials are also suited to corers. Peat borers have a
specific application.
4.3.1.2.2 Type of bed
4.3.2.3 Accuracy of Sample
The System is most suitable for sampling Sediment
beds consisting of silt and/or sand and gravel. lt is not
Most corer samples are relatively undisturbed and
suitable for sampling peat, clays or gravel beds in riffle
may be used to defin
areas. e strata.

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ISO 5667=12:1995(E) 0 ISO
there tan be Problems in obtaining samples when
4.3.2.4 Nautical conditions
working from the bank where a distance of more than
4 m must be bridged by rods. Due to movement of a
Hand-operated types are prone to nautical constraints
vessel, it is often difficult to obtain good samples from
such as fast flow or high Winds in small boats. They
are usually confined to use at shallow depths unless a boat. However, it is possible to obtain reliable sam-
a diver is employed. ples in a water depth of approximately 2 m; beyond
this a diver may need to be employed.
Mechanical devices tan be used remotely from boats
Various types of manually operated corers with a
and are more suitable for use in rough weather. They
are not recommended for use from bankside or multitude of modifications, all based on the same
bridges. principle, are in use. The characteristics of a number
of types of corer Systems and recommended typical
applications are described in 4.3.2.6.1 to 4.3.2.6.5.
4.3.2.5 Other information
4.3.2.6.1 Piston drill
So-called “pile-working” (3.2) tan occur with corer
Systems. The amount of pile-working depends on
The Piston drill is recommended for Chemical, physical
such variables as the diameter of the tube, the com-
and biological investigations. lt is suitable for use in
Position of the bed and the Penetration Speed. lt is
sampling beds consisting of consolidated silt and/or
difficult to judge when this phenomenon is recurring,
in peat. lt is not recommended where the Sediment
as each location is different, and interpretations
bed consists of fine sandy or silty material, as there
should be made with caution.
is a possibility that the Sample will be lost from the
Evidente tan be found by observing distortions in the bottom of the core tube because it is not closed off
strata indicating compression at the centre of the core underneath.
and a lack of movement at the core peripher-y during
sampling. In general, a concave appearance will pre-
4.3.2.6.2 Corer System involving a diver
dominate from the bottom of the Sample up. The
consequences of this occurring vary depending on the
In this System a corer tube is pushed into the
reason for occurrence and the end use of the Sample.
Sediment by a diver. If necessary, the tube tan be
Stratification studies tan be acutely hampered by this
coupled to a vacuum pump so that the Sample tan
lt is possible that the only way to
phenomenon.
be taken up into the tube more easily. Maximum
overcome the Problem may be to use a different
Penetration is 2 m.
technique, for example a core tube with a larger di-
ameter. Lubrication of the inside of the Sample tube The diver core tube is applicable to Chemical, physical
should only be used with the agreement of the lab- and limited biological investigations.
Orator-y carrying out subsequent testing.
4.3.2.6.3 Beeker core Sampler (see annex D)
A cored Sediment Sample frequently requires dimen-
sionally accurate subsampling in Order to take full ad-
The tube is mounted on a Cutter head containing an
vantage of subsequent laboratory analysis and
inflatable bellows which prevents the Sample from
interpretation. The extrusion device tan be a simple
falling out of the tube when it is withdrawn from the
Piston or a variety of fixtures using a stationary vertical
Sediment.
Piston over which the core tube is placed. The
extruded material tan be sectioned with a device,
4.3.2.6.4 Sealed core Sampler (see annex E)
which tan be put on the top of the sampling tube. The
Sample tan be simply removed with a spoon or, if the
The stainless steel tube containing a plastics inner
Sediment is solid enough, a spatula. The material of
sleeve is closed off by inflating two small bellows,
the corer or sectioning devices should be Chosen so
one at the top of the tube and one in the Cutter head,
as not to conflict with any Chemical analysis.
so that when the tube is removed from the Sediment
the Sample does not fall out.
4.3.2.6 Manually operated sampling apparatus
As long as its Iimitations are taken into account, the
In this apparatus the tube is pushed into the bed by sealed core Sampler tan be used for physical, chemi-
cal and limited biological investigations. lt is suitable
means of rods. Penetration is generally up to a maxi-
for silty and fairly soft water beds and tan be operated
mum of 2 m, depending on the nature of the bed
from a (small) vessel or from shore (for example from
materials. Gravels are unlikely to be suited to this
sampling method. Because extension rods are used, a Pier, quay or bridge).
4

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0 ISO ISO 5667012:1995(E)
mud
NOTE 2 The terms hard and soft (as used in this part of 4.3.3.2 Jenkins Sampler Sampler
ISO 5667) are largely arbitrary and a certain amount of trial
(see annex H)
and error will have to be employed when assessing the
suitability of certain Sampler types to those particular
The corer is mounted in a frame and due to its large
physical Sediment characteristics.
mass it sinks into the bed. Once the Suspension cable
is slackened sufficiently, a closing mechanism is acti-
Because the top and bottom of the tube tan be shut
vated which shuts off the Sample tube by means of
off, the Sample tan be collected undisturbed. Use of
hinged arms.
the Sample-removal apparatus often supplied with the
sealed core Sampler tan allow various strata to be
The Jenkins mud Sampler is suitable for physical,
sampled accurately.
Chemical and limited biological investigation of the top
layer of very soft beds. lt is not suitable for hard
WARNING - The Chance of “pile-working” is high
Sediment beds. By shutting the valves gently using
in consolidated silt. In this case, the Penetration
anoil pressure device, an undisturbed Sample of the
depth is greater than the compressed strata depth
soft top layer of Sediment tan be obtained.
of the Sample in the core tube. This should be
borne in mind during the sampling Operation and
The bed needs to be soft since the valves do not shut
when interpreting the core.
properly if the bed is hard, due to the resistance ex-
perienced, and the core tube will not penetrate.
When using a boat it is important that it remains
Samples tan be taken in deep water.
stationary so that, when the core tube is pushed
into the Sediment, the vessel is not pushed away.
There is a possibility of the vessel being moved 4.3.3.3 Craib corer Sampler (see annex J)
against the rods by wind or currents. This should
be prevented in Order to avoid darnage to the The Craib corer consists of a core tube mounted in a
sampling equipment and boat. frame. When it is lifted out of the Sediment layer, the
core tube is first closed off at the top by a valve. As
The consistency of the bed largely determines the soon as the bottom is free of the bed, it is closed off
sampling result. Because of its construction (air and by a ball.
pressure hoses) the apparatus is only usable in silty,
fairly soft beds up to a water depth of approximately
4.3.3.4 Easy All core Sampler
3 m.
The Easy All is a corer whose mass tan be increased
4.3.2.6.5 Vrijwit drill or wedge corer
to approximately 110 kg. After the Sample has been
(see annex F)
taken, the core tube is shut off at the top and the
bottom by means of valves. The filled core tube tan
The wedge core tube has a maximum Penetration of
be removed from the holder completely once it is
1,50 m. One side of the wedge remains open whilst
aboard. lt is also possible to take readings directly
it is pushed into the Sediment. The open side of the
from the core material by inserting electrodes in tiny
core tube is then closed off with the slider, and the
side openings in the tube Wall. Parameters such as
Sample is extracted from the Sediment.
temperatures and redox potential tan be studied eas-
ily.
4.3.3 Mechanically operated sampling apparatus
Many types and modifications are in use. Subclauses 4.3.3.5 Vibro corer Sampler
4.3.3.1 to 4.3.3.8 describe the characteristic proper-
A casing containing a polyvinylchloride tube is pushed
ties of a number of common types and recommend
into the bed by means of weights and a Vibration
typical applications and suitability to various types of
Sediment. mechanism. A Piston ensures that the Sample tan be
moved into the tube more easily. When the core tube
has reached the required depth, it is removed from
4.3.3.1 Falling bomb core Sampler (see annex G)
the Sediment bed. A core Catcher and the Piston en-
Sure that the Sample does not fall out of the tube.
The core tube is mounted in a weighted holder which
is dropped freely from a vessel and penetrates the Penetration depths of various Vibro corers vary be-
Sediment. The method is fast and efficient because it tween 1,2 m and 6 m. The total mass is approxi-
is not necessary for the vessel to be anchored. This mately 850 kg. A vessel with a lifting capacity of at
method is not suitable for use in unconsolidated least 1 000 kg is necessary if the Vibro corer is to be
used. This type of Sampler consists of highly special-
Sediments.
5

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ISO 5667=12:1995(E) 0 ISO
Charge or tributary to be well mixed laterally before
ized equipment and its use is considered to be be-
yond the scope of this part of ISO 5667. the Station.
Low-frequency echosounders should be considered
4.3.3.6 Piston corer Sampler (see annex K)
to assist in locating bed areas of appropriate quality
Prior to sampling.
The Piston corer consists of a core tube which is
weighted at the top and tan have fins for added
The criteria for choice tan include:
stability. Its Operation depends on the free fall prin-
ciple.
- ease of repeat access to the location, for example
a tidal influence;
4.3.3.7 Peat borer
- seasonal availability, for example, affected by
These devices generally comprise hand augers
safety, Problems in Spate;
specifically designed to tut cores out of saturated or
partially drained peat Sediments. Some examples - the influence of marine traffit, for example, sam-
from the Polish Peat Institute are given in annex L. ple Points may need to be avoided due to traffit.
4.3.3.8 Cold finger techniques
5.2 Choice of sampling Point
During the preparation of this part of ISO 5667 it was
This will be influenced by physical constraints such
noted that some success has been reported in the
as boat size or water depth but the precise Point will
Iiterature with the use of “cold finger” sampling of
largely depend upon the purpose of the investigation.
Sediments. This involves the insertion of a refrigerated
For example, if geophysical mapping is the sole pur-
device into the Sediment which freezes a Portion of
pose then choice may be the function of flow and
its surroundings allowing stratigraphical extraction and
current conditions whereas if Chemical
only,
Separation. Users of this patt of ISO 5667 are recom-
composition/contamination is being studied, the sam-
mended to refer to the Iiterature sources cited in the
pling Point will depend largely on the geophysical
bibliography in annex M for more details of the scope
condition of the bed areas. For instance, it would not
of application.
be expected to find contamination caused by gross
metals in a riffle area of a stream compared to a pool
area. The choice of sampling Point will be a desirable
5 Sampling procedure
pre-qualification for the Programme, but exact lo-
cations will inevitably be revised in the field.
5.1 Choice of sampling site
Locations will need to reflect the proximity to Outfalls,
In choosing the exact Point from which samples are the influence of stream mixing and other factors such
required, two aspects are generally involved: as plant growth.
the selection of the sampling site (i.e. the location
a)
5.3 Choice of sampling method
of the sampling Cross-section on the base of the
water body);
The choice of sampling method will largely be re-
stricted by the two following factors.
the identification of the precise Point at the sam-
W
pling site.
a) The requirement for a largely undisturbed Sample
The purpose of sampling often precisely defines
for stratigraphical delineation.
sampling sites (as is the case when studying depo-
sition from a particular discharge Point), but some- b) The acceptance of a disturbed Sample taken near
times the purpose only leads to a general definition the bed surface for a general morphological or
of the sampling site as in the characterization of the Chemical examination.
quality and type of material in a river delta.
These factors will be decided upon during the pro-
The choice of sampling sites for Single sampling gramme design Stage. Certain types of Chemical par-
stations is usually relatively easy. For example, a ameter may necessitate the use of inert Iiners in
monitoring Station for a baseline record of Sediment Piston
...