SIST-TP CEN/TR 16365:2013

SLOVENSKI STANDARD
01-januar-2013
.DUDNWHUL]DFLMDRGSDGNRY9]RUþHQMHRGSDGNRYL]LQGXVWULMHERJDWHQMDPLQHUDOQLK
VXURYLQ
Characterization of waste - Sampling of waste from extractive industries
Charakterisierung von Abfällen - Probenahme von Abfällen aus der mineralgewinnenden
Industrie
Caractérisation des déchets - Echantillonnage des déchets issus des industries
extractives
Ta slovenski standard je istoveten z: CEN/TR 16365:2012
ICS:
13.030.10 Trdni odpadki Solid wastes
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL REPORT
CEN/TR 16365
RAPPORT TECHNIQUE
TECHNISCHER BERICHT
October 2012
ICS 13.030.10; 73.020
English Version
Characterization of waste - Sampling of waste from extractive
industries
Caractérisation des déchets - Echantillonnage des déchets Charakterisierung von Abfällen - Probenahme von Abfällen
issus des industries extractives aus der mineralgewinnenden Industrie

This Technical Report was approved by CEN on 13 May 2012. It has been drawn up by the Technical Committee CEN/TC 292.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 16365:2012: E
worldwide for CEN national Members.

Contents
Foreword .3
Introduction .4
1 Scope .6
2 Key elements of a sampling plan .6
2.1 General .6
2.2 Identify involved parties (EN 14899:2005, 4.2.1) .6
2.3 Identify general objectives (EN 14899:2005, 4.2.2) .8
2.4 Collect background information and undertake field inspection (EN 14899:2005, 4.2.5) .8
2.4.1 General .8
2.4.2 Existing information .8
2.4.3 Field inspection .9
2.4.4 Analogous sites . 10
2.5 Determine specific objectives and corresponding level of testing (EN 14899, 4.2.3) . 10
2.5.1 Introduction . 10
2.5.2 Determine the level of testing . 11
2.5.3 Determine the required number and size of samples . 13
2.6 Identify constituents to be tested (EN 14899:2005, 4.2.4) . 14
2.7 Identify health and safety precautions (EN 14899:2005, 4.2.6) . 14
2.8 Select sampling approach (EN 14899:2005, 4.2.7, and CEN/TR 15310-1:2006, Clause 4) . 15
2.8.1 General . 15
2.8.2 Determine the practical instructions . 23
2.9 Identify the most appropriate sampling technique (EN 14899:2005, 4.2.8, and
CEN/TR 15310-2) . 29
3 Sample handling in the field . 33
3.1 General . 33
3.2 Sub-sampling . 34
3.3 Sample preparation and storage (CEN/TR 15310-4). 35
3.3.1 General . 35
3.3.2 Packaging . 35
3.3.3 Preparation and storage . 36
3.4 Transport the sample to the laboratory (EN 14899:2005, 5.2, and CEN/TR 15310-4) . 37
4 Documentation (long and short form of sampling plan) . 37
4.1 Document the sampling plan and produce instructions for the sampler (EN 14899:2005,
Clause 6) . 37
4.2 Produce a field sampling record (EN 14899) . 37
5 Sampling (EN 14899:2005, 5.1) . 38
6 Sampling uncertainty and other issues . 39
Annex A (informative) Example sampling plans for waste characterization for exploration,
operation and closure stages of extractive industries . 40
A.1 General . 40
A.2 Example detailed sampling plan for exploration stage . 40
A.3 Example short form sampling plan for exploration/ permitting stage . 47
A.4 Operation stage – Simple system – Aggregate quarry . 49
Annex B (informative) Example sampling record . 53
Bibliography . 54

Foreword
This document (CEN/TR 16365:2012) has been prepared by Technical Committee CEN/TC 292
“Characterization of waste”, the secretariat of which is held by NEN.
The preparation of this document by CEN is based on a mandate by the European Commission (Mandate
M/395), which assigned the development of standards on the characterization of waste from extractive
industries.
This Technical Report is intended to supplement the existing series of five Technical Reports dealing with
sampling techniques and procedures for waste, and provides specific information for sampling of waste from
the extractive industry. It follows the principles laid down in EN 14899, Characterization of waste  Sampling
of waste materials  Framework for the preparation and application of a Sampling Plan. Further information
on the relationship between the production of a sampling plan and the overall testing programme objectives
can be found in CEN/TR 15310-5.
 CEN/TR 15310-1, Characterization of waste — Sampling of waste materials — Part 1: Guidance on
selection and application of criteria for sampling under various conditions;
 CEN/TR 15310-2, Characterization of waste — Sampling of waste materials — Part 2: Guidance on
sampling techniques;
 CEN/TR 15310-3, Characterization of waste — Sampling of waste materials — Part 3: Guidance on
procedures for sub-sampling in the field;
 CEN/TR 15310-4, Characterization of waste — Sampling of waste materials — Part 4: Guidance on
procedures for sample packaging, storage, preservation, transport and delivery;
 CEN/TR 15310-5, Characterization of waste — Sampling of waste materials — Part 5: Guidance on the
process of defining the sampling plan.
This Technical Report focuses mainly on sampling for geochemical rather than geotechnical requirements.
Sampling for geotechnical requirements is only addressed to a limited extent and references are made to
existing documentation. The Technical Report elaborates on a range of potential approaches and tools of
specific relevance to the sampling and testing of wastes from the extractive industry. This approach enables
the project manager to tailor his sampling plan to a specific testing scenario and continues the ‘shop shelf’
approach to sampling plan development for waste testing outlined in CEN/TR 15310-1 to -5. This approach
allows flexibility in the selection of the sampling approach, sampling point, method of sampling and equipment
used. It provides the necessary background information pertaining to the factors that influence the choice of
these detailed components of the sampling exercise, and information on the necessary statistical choices that
can then be applied to determine the most appropriate testing programme for any given sampling scenario.
This Technical Report also makes references to the overall guidance document for characterization of waste
from extractive industries (CEN/TR 16376) which gives guidance and recommendations on the application of
methods for the characterization of waste from extractive industries.
Introduction
The guidance outlined in this Technical Report is focused on the key elements to be considered in the
development of a sampling plan for extractive waste. This report should be used in conjunction with EN 14899
and its supporting technical reports and is intended to supplement the information contained in these
documents with specific and essential information relevant to the sampling of waste from the extractive
industry. Where appropriate this report also makes reference to the overall guidance document for
characterization of waste from extractive industries (CEN/TR 16376) which gives guidance and
1)
recommendations on the application of methods for the characterization of waste from extractive industries .
1) Specific features of extractive waste
The extractive industry includes, metal mines, rock quarries, salt mines, coal mines, sand and gravel,
limestone and onshore oil and gas operations. When mineralogical material is extracted it is exposed to
changes in physico-chemical conditions, which may result in chemical and physical instability of previously
stable geological material.
The life cycle of extractive industries starts with the early phase of exploration through operation to closure
and after care. In the context of sampling three phases have been defined in this document:
 exploration (including design and permitting);
 operation (extraction and processing, including transport and deposition of waste); and
 closure (including existing waste deposits).
From a sampling perspective different sampling scenarios may be more relevant than the operational phases.
For example sampling from diamond drill cores may take place both during exploration and operation,
sampling at existing waste rock dumps and tailings facilities may take place both during operation and at
closed sites. Both operational phases and sampling scenarios are used as parallel concepts in this document.
One significant feature that makes characterization of extractive waste different from waste characterization in
general is the fact that sampling and characterization ideally take place before the waste is produced, i.e.
based on drill cores (or drill mud) from exploration drilling. Characterization during exploration is critical since
subsequent waste management plans are developed on the basis of this information. However, the availability
of material for sampling and characterization at the exploration stage is commonly limited which means that
follow-up checks to ensure that the initial data and interpretation are correct will often be needed during
operation. If pilot scale tests, extraction and/or processing, are carried out this will have the added benefit of
producing a larger number of potential samples for sampling and testing as well as giving the opportunity to
sample process waste, i.e. tailings. While the majority of waste is commonly produced during the operation
phase of a mine, waste characterization needs to be considered for all phases of the mine life.
The operational phase of a mine or quarry encompasses all the activities from mineral deposit development to
detailed planning for closure. There are two main waste streams from the production process that need to be
characterised, i.e. waste material generated as part of the extraction that will not go through mineral
processing and the waste produced during processing. The waste produced prior to mineral processing will
primarily be waste rock separated at the excavation front. In a hard rock mine, sampling may be done before
blasting from drill cores, or after blasting. After mineral processing the waste will primarily be tailings (i.e. tail
end of the process), and samples may be collected from pipelines, discharge trenches or conveyer belts.
Extractive waste may contain chemicals added as part of the production process. Normally, if not recovered
for construction purposes, all extractive waste is deposited on site.

1) As defined in Directive 2006/21/EC.
This guidance is also applicable for sampling from closed sites in case sampling and testing of waste is
required. Sampling at closed sites, including abandoned historic mine-sites, may in some cases require
specific approaches e.g. due to accessibility and limited background information.
NOTE Given the great variety of waste types, sampling situations and objectives, this Technical Report cannot
provide definitive instructions that cover all scenarios. Instead, it discusses the basic considerations to be followed, and
provides guidance on selection of sampling approaches that might be relevant to the three principle phases of a mine:
1) Exploration, 2) Operation and 3) Closure. Sampling of existing waste deposits at mines that are still in operation would
be very similar to Scenario 3) Closure.
2) Document structure
The structure of this sampling guideline is based on the concepts and procedural steps outlined in Figure 2 of
EN 14899:2005 and subsequent subclauses, with some additions to address specific features of the extractive
industry.
Clause 2 key elements of a sampling plan, is the core of this guidance document. This clause is divided into
ten sub-sections that describe the steps of developing sampling plans, from defining the involved parties to
describing the sampling techniques. It lists possible objectives for the different stages of the extractive waste
characterization, background information that may be available, explains generic levels of testing and
describes sampling approaches and techniques.
1 Scope
This Technical Report gives additional and specific information on sampling for testing of waste from the
extractive industry to support the development of appropriate sampling plans. This supplementary guidance to
EN 14899 is required because waste from the extractive industry differs considerably from the waste types
and sampling scenarios covered in the existing technical reports (CEN/TR 15310-1 to -5) that support the
Framework Standard. This guidance document should be used in conjunction with EN 14899 and its
supporting technical reports CEN/TR 15310-1 to -5.
The approach to sampling described in this document is primarily focused on the requirements to undertake
mineralogical and geochemical testing of the waste. Whilst much of the background information provided is
also relevant to geotechnical investigations there may be important additional requirements or differences in
approach for determining relevant physical parameters. For example, many geotechnical parameters are
determined using field tests, which are not discussed in this document. References to alternative source
documentation are provided.
The guidance provided in this document applies only to above-ground exposure to radio-nuclides present in
the undisturbed earth crust and not to the production, processing, handling use, holding, storage, transport, or
disposal of radioactive substances that are or have been processed for their radioactive, fissile or fertile
properties.
This Technical Report provides some discussion of current best practice, but is not exhaustive. To clarify the
text, the document provides a number of worked examples in the Annexes.
2 Key elements of a sampling plan
2.1 General
The sampling plan identifies the appropriate and practical activities required to achieve the set objectives of
the characterization testing programme. The purpose of a sampling exercise shall be clearly understood by
the sampler. The development of a sampling plan helps to ensure that the objectives of any waste testing
programme are consistently met and is crucial for cost effective and appropriate sampling. The sampling plan
provides traceability which can be used to validate the data produced. This is especially important where new
datasets will be generated over time.
The framework standard EN 14899 identifies a process flow chart that defines the essential elements of a
sampling plan and how those elements are linked. The basic steps identified in this flow chart have been
followed in this supplementary guidance, with some minor changes (see Figure 1) to account for specific
circumstances of the extractive industry. The flow chart indicates a step by step process to sampling plan
development, although in reality they may be considered out of order. Some elements of the sampling plan
may be prepared in parallel and iterations may be necessary. Additional information is provided in the
following sections that are specific to the extractive industry.
It is important to recognise that characterization may often be an iterative process. The sampling plan may
initially be developed for screening purposes and may then form the basis of a characterization study. The
characterization study may require testing of samples previously collected but not subjected to testing or form
the basis for collection of more samples required for more comprehensive testing all specified in the sampling
(Figure 1).
Characterization of waste from a quarry may be relatively simple in comparison to wastes from metal
extraction. However, generating a sampling plan using the outline approach advocated in this guidance
document is still recommended. Development of a comprehensive sampling plan will facilitate discussions
with stakeholders, and it may help the operator to identify issues that may require consideration.
2.2 Identify involved parties (EN 14899:2005, 4.2.1)
It is recommended that sampling plans for a given site and phase of operation are, where possible, discussed
with involved parties prior to any sampling taking place. It is important to identify and include parties with an
interest at an early phase in the testing programme. This may include e.g. people from different parts of the
organisation of the operator, consultants, regulators and local stakeholders. This approach may avoid or
minimise confusion at a later date and facilitate acceptance from involved parties. Well-communicated
sampling plans may provide confidence that the results generated from the sampling and testing programme
will be valid.
The numbers in the chart refer to the clauses within this document.
Figure 1 — Flowchart of sampling plan modified from Figure 2, EN 14899:2005
2.3 Identify general objectives (EN 14899:2005, 4.2.2)
The overarching objectives of a testing programme define the type and quality of information required from
sampling and analysis. During the various phases in the life of a mine there may be more than one objective
and therefore a need for more than one sampling plan. Whilst the overall objective can be identified prior to
any background data collection and on-site investigation the technical objectives can usually only be set once
this information has been gathered.
Example overarching objectives may be to contribute data to:
 design a waste facility;
 development of a waste management plan;
 design/evaluation of closure options;
 design/evaluation of management options for abandoned sites.
The overall guidance document (CEN/TR 16376) includes a discussion on when and why characterization
may be needed and the context within which characterization data may need to be applied. However, it does
not cover information on how to apply these characterization results, e.g. for dam design or closure planning.
For guidance on how to use characterization results correctly for predictive modelling or design purposes
references are made to other sources of information.
2.4 Collect background information and undertake field inspection (EN 14899:2005, 4.2.5)
2.4.1 General
It is essential to obtain pertinent background information to develop good sampling plans for future, existing,
closed and abandoned facilities. The background information allows the development of clear and precise
instructions for sampling. Background information can be divided into three categories: existing information
including site background information; field inspection information; and analogous geology. These three
categories are discussed in the following clauses.
2.4.2 Existing information
Obtaining background information on a proposed extractive operation and collating this information to feed
into the development of a testing program and sampling plan is essential when defining appropriate detailed
objectives for sampling and testing. Careful inclusion of valid prior information can greatly reduce the cost per
unit of error and dramatically reduce the size of the samples required. Relevant existing information may
include data from previous exploration work as well as investigations carried out for other land uses or local
data on background concentrations of key constituents in soils surface waters.
The use of existing information would typically be complemented by a field visit. It is important to emphasise
that although existing data may be very useful, its relevance should be evaluated prior to using the data in any
decision making process. If data is available from previous sampling programmes, the evaluation of suitability
would include looking at the:
1) type of sampling undertaken;
2) consistency of test data and analytical procedures used;
3) objectives of previous sampling and testing.
If a site moves from exploration to operation a new sampling plan will need to be developed and the waste
characterization data used for design and permitting will then become the background information for the
operation stage.
The overall guidance document (CEN/TR 16376:2012, Clause 5) gives further recommendations on site
background information that may be useful.
2.4.3 Field inspection
A field inspection provides valuable information on local conditions, e.g. any access restrictions that may
impact upon the planned sampling approach e.g. appropriate selection of sampling points. The information
that may be gathered by a field inspection will be very different for an exploration site compared to an on-
going operation or a closed waste facility. Examples of information that should be collected include:
a) Exploration
1) topography, accessibility;
2) geology;
3) mineralogy/iron phases in drilling material, overburden and exposed bedrock;
4) relevant environmental factors.
b) Operation
1) accessibility;
2) geology;
3) mineralogy/iron phases;
4) additives;
5) grain size variation;
6) erosion features and slumping;
7) excavation and transport methods;
8) material type (tailings, waste rocks);
9) potential hazards;
10) relevant environmental factors.
c) Closure and closed sites
1) accessibility;
2) geology;
3) mineralogy/iron mineral phases;
4) seepage/seepage colour and possible field measurements of seepage;
5) water/air erosion features at disposal facilities;
6) grain size variation;
7) slumping;
8) potential hazards;
9) relevant environmental factors.
Signs of water and air erosion, especially on tailings, can indicate, to some degree, the extent to which the
waste material has been transported from its original position. The following information can be used to
identify the area to be sampled.
 erosion features;
 aeolian transport of tailings from original deposit;
 stability of existing tailings and waste rocks.
Mapping the deposit mineralogy and the presence of iron phases (for sulfide containing mineralisation) is an
essential part of evaluating the risks associated with current and future waste from the site. The mineralogy
rather than the bulk chemistry provides a first indication of potential drainage quality, acid generating minerals,
and neutralizing minerals. If the rocks have been exposed to air and water variations (where groundwater is
being lowered due to pumping) over short or long periods, secondary minerals may give an indication of how
the waste will behave when it is subsequently exposed to air and water.
The type of processing and use of additives, and type of waste being generated will give an indication of the
type of analyses that may be necessary and define health and safety precautions during sampling and
handling of the samples. If first evaluation indicates that there is a potential for acid/neutral rock drainage
(A/NRD) or leaching from tailings, it may be necessary to obtain samples from a pilot processing plant.
The presence of seepage, colour and field measurements of the seepage, aid in defining, for example, the
level of testing and type of analysis. These observations and field measurements give an indication of the
oxidation reactions and leaching taking place within the waste material. For example:
 Drainage pH and total dissolved solids may indicate if there is already A/NRD or alkaline drainage from
existing waste dumps or from the mineralization of in situ outcrops.
 Colour of drainage water or waste rock may provide an indication of A/NRD or alkaline drainage and the
rock’s neutralizing potential and reactivity. The colours yellow, orange, red, brown are commonly linked
with different iron phases precipitated as a result of acid drainage.
2.4.4 Analogous sites
During evaluation of background information it may be possible to identify where the mineral deposit has
analogous sites with information. Information from the analogous sites may be used to identify key issues and
help focus the sampling plan on relevant aspects. In some cases this information from the analogous sites
may replace the need to undertake some or all of the planned sampling.
2.5 Determine specific objectives and corresponding level of testing (EN 14899, 4.2.3)
2.5.1 Introduction
The technical objectives of a testing programme and sampling plan, which may be numerous, affect the
location, number and volume or weight of samples taken, minimum testing requirements and precautions
needed to preserve sample integrity during transport to the laboratory. The same samples can often be used
for several tests. By identifying all the data requirements prior to collecting any sample and by storing samples
in such a way that their integrity is maintained, they can be used for multiple tests and also re-used at a later
date.
2.5.2 Determine the level of testing
Examples of potential sampling objectives linked to the phases of operation and related sampling scenarios at
an extraction site or mine are provided in Figure 2 and Table 1. There are a couple of worked out examples of
sampling plans to illustrate the variety of sampling plans for different type of operations in the annexes from
the complex metal mining during permitting phase to simple quarry operations during production with
confirmation testing. Moreover, the overall guidance document gives examples of typical questions to be
answered and guidance on methods available for determination of specific properties.

Figure 2 — Schematic of phased operation of mineral extraction linked to potential sampling
objectives
In the context of waste characterization for the extractive industry at least three main objectives (Table 1) can
be readily identified:
Screening characterization: this objective, sometimes termed basic characterization, applies typically for the
waste rock characterization during the exploration stage where waste-rock samples are commonly taken from
drill cores. Screening typically includes a set of quick and simple tests to get an overall picture of waste
categories and variability. The screening is commonly performed early during the exploration phase,
especially if sulfides are present. Screening level testing may be all that is performed or necessary to perform
for mineral deposit that is not likely to generate drainage with poor quality water.
Table 1 — Example sampling objectives linked to the different phases of an extraction site or mine
Phase Code Scenario Material type Objective
rock cores, Screening or
Exploration E1/E2/E3 Anticipated extractive wastes from exploration
cuttings, sludges, Comprehensive
(E) or development by sampling excavation fronts
in-situ rock characterization
or drill material.
in-situ rock Comprehensive
Operation O1 Blasted rock from excavation front during
characterization
(O) operation.
or Confirmation
dry coarse rock, Comprehensive
O2/O3/O Excavated or processed waste in pipelines or
wet coarse rock, characterization
4/O5 on conveyer belts.
wet fines; dry or Confirmation
fines, tailings
slurry (clay to
coarse sand)
coarse rock, dry Comprehensive
O6/O7 Extractive waste in existing dumps.
fines characterization
or Confirmation
dry coarse rock, Comprehensive
O8 Exploration or development drill material.
wet coarse rock, characterization
wet/dry fines or Confirmation
dry coarse rock, Comprehensive
O9 Blast material from excavation front.
wet coarse rock,
characterization
wet/dry fines or Confirmation
coarse rock, dry Screening,
Closure (C) C1/C2/C Extractive waste in existing dumps.
fines, Comprehensive
3/C6
characterization
or Confirmation
saturated fines, Screening,
C4/C5 Previously deposited tailings.
unsaturated fines Comprehensive
characterization
or Confirmation
Comprehensive characterization: for a new operation, this may be performed later in the exploration phase.
Comprehensive characterization typically includes more costly and time consuming test work like leach tests
and/or kinetic testing together with a higher number of samples. Comprehensive characterization may not be
needed when screening gives a clear result with an appropriate level of confidence. For current operations
there may be a need to perform comprehensive characterization if this was not performed before or if the
composition of the waste has changed significantly.
Confirmation testing usually consists of a few samples collected and tested for key parameters identified
through the comprehensive characterization in order to determinate whether waste produced conforms with
expected results, e.g. fits with the design criteria/requirements set in the permit or specified in the waste
management plans. The testing programme will commonly be built upon the results from screening or the
comprehensive characterization. Due to the long life-time of a typical mine, significant amounts of data are
likely to result from on-going confirmation testing, which should be used for continual updating of waste
management and closure plans.
The objective shall also be linked to the ‘population’ that requires evaluation. In the evaluation of the variability
the ideal aim is to have access to the whole population that requires evaluation, whilst during confirmation
sampling access is typically reduced to identify sub-populations within the waste (e.g. a waste stream
generated under a certain condition in a fixed time regime). For example confirmation samples taken from drill
cores or pipelines during the operation of the mine give access to an easily defined sub-population. When
sampling from a dump or a dam, commonly only the perimeters are sampled and thus the samples are
commonly not representative of the whole “deposited tailings” population (this would require that every particle
of waste has an equal chance of being sampled).
In the majority of cases the general objective (2.3 and the more specific objectives) of a testing programme
are too general to be useful as an unambiguous instruction to the sampler. It is, therefore, necessary to
translate this objective into a number of practical technical goals, which provide a more detailed specification
for the sampling activity, which can then be further developed and linked to specific sampling and analytical
requirements.
Commonly a phased approach will be needed to meet each technical goal; each may require its own specific
sampling plan.
An example where a general objective is translated into a technical goal or instruction might be:
The objective of the sampling and testing programme is to evaluate the general acid base accounting (ABA)
characteristics of a mineral deposit, with known carbonates and variable sulfide, for different geological units.
The associated technical goals might be in two parts; the first would be to sample the geological units and test
for total sulfur, ABA and mineralogy (screening). The second technical goal could relate to a targeted second
round of sample collection and analysis using the results of the phase I testing (comprehensive sampling and
testing).The specific objectives may range from simple field confirmation, like observing if the colour is
constant or that a specific mineral is present or not present, to very detailed objectives as part of a
comprehensive characterization scheme.
2.5.3 Determine the required number and size of samples
The number of samples required for source characterization of each material type depends on the following:
a) the amount of disturbance (i.e., the volume/mass of material extracted or the amount exposed on pit/mine
walls or production tonnage as determined by the block model);
b) the compositional variability within a material type; and
c) the statistical degree of confidence that is required for the assessment.
Initial estimates of sample numbers are typically based on professional judgment, and experience. The
number of required samples typically grows during each of the early phases of mine development as the
knowledge base and project needs grow. Ultimately, for sites characterized as having ARD potential, a full
geostatistical model often provides the basis for control plans where material segregation is part of the mine
plan. (GARD, 2009)
The size of the samples to be collected is in many cases dictated by the required analytical methods. However,
it is recommended that a larger sample (3 kg to 4 kg) is collected to ensure representativity and ensure
adequate sub-sample size for each analytical test. If the objective is comprehensive characterization of the
waste material, several samples may be needed for each of the test methods and substantially larger samples
may be needed. Although many of the laboratory test methods require only 100 g to 200 g of material,
ensuring that the sample is representative requires due consideration of the particle size and variability at the
scale of sampling.
Relatively undisturbed samples may also be useful when performing leach tests/column-kinetic tests on
coarser tailings material. The sample can be collected in a Plexiglas/acrylic (or similar) cylinder. By using such
a sample it is possible to approximate the original flow path of the material for both water and oxygen and,
thereby, obtaining more reliable/applicable results than if using a grab sample (see 2.9.3.4).
The number of samples will be dependent on some or all of the following aspects:
 stage of the project;
 complexity of the geology;
 questions to be answered (objectives);
 type and complexity of the operation;
 environmental issues of concern;
 degrees of uncertainty required or accepted;
 variability in the material of parameters to be analyzed.
The number of samples that should be collected is difficult to evaluate before an initial dataset has been
generated. The BC Guideline (1990) suggests for potential sulfidic waste, a minimum amount of samples as a
function of mass of waste unit (10 000 ton > 3 samples; 100 000 > 8 samples; 1 000 000 > 25 samples, 10
000 000 > 80: 100 000 000 > 260 samples). This system was based on the experience of the authors of the
document. Australian Guidance on sample numbers for mining environmental assessment (2007) does not
specify sample numbers. It describes the need for increased numbers of samples as the exploration project
develops and that an optimum number of samples should be collected as part of the permit application.
2.6 Identify constituents to be tested (EN 14899:2005, 4.2.4)
The sampling plan should identify the properties (e.g. colour, grain size, hydraulic conductivity) and
constituents (e.g. elements and mineral concentrations) to be investigated. These will depend on the material
type and the objectives of the testing programme which will differ between extractive sectors, geographical
locations and phases of the operation. Examples of specific information that may be relevant are given below.
 mineralogical analysis (identification of minerals, texture);
 geotechnical methods (e.g. soil index properties such as grain size distribution; specific surface, specific
weight; Atterberg limits; and permeability; as well as mechanical properties such as shear strength; and
compressibility);
 geochemical analysis (content of sulfur species, metals, static tests, kinetic tests);
 leaching tests;
 biological tests (ecotoxicity test, microbes in the waste material, growth potential).
Furthermore, the texture and grain size of the material can dictate choice of tests and therefore of sampling
techniques (see 2.9.3, 2.9.3.3, 2.10 and Clause 3),
2.7 Identify health and safety precautions (EN 14899:2005, 4.2.6)
The sampling plan should identify all necessary health and safety precautions that should be followed during
the sampling programme. It is recommended that a hazard assessment is carried out before any sampling at
a site to protect, and minimise any risks to, or created by, those involved in on-site activities. The type of
health and safety equipment that may be needed on site to perform sampling according to the sampling plan
should be specified. Any organisation involved in sampling would be expected to have a health and safety
policy that sets out the requirements of safe working.
The health and safety issues are commonly very different for the exploration phase of mining relative to the
operational phase, and again different from the issues that may arise in sampling of closed/abandoned waste
deposits. However, some general issues can be identified for all three settings and especially to the
production of emergency plans in the event of an accident taking place during sampling.
A mine should have a detailed health and safety plan, in which case the sampler should be aware of it, and in
some cases, be trained by the operational personnel. Some general health and safety issues may include:
 very large equipment (e.g. 320 tonne trucks) where driver visibility is greatly reduced at close range
(e.g. 30 m);
 dumping of waste material on areas to be sampled;
 unstable out-slopes;
 saturated tailings;
 loose material in the production phase;
 unstable material in pits, trenches and underground tunnels;
 poor air quality as a result of mineral reactions (e.g. H S, CO , CO or CH gas) or from the equipment
2 2 4
used; and
 dust problems.
Detailed guidance on safety during site investigations and sampling is given in ISO 10381-3 and in
EN 14899:2005, 4.2.7.
2.8 Select sampling approach (EN 14899:2005, 4.2.7, and CEN/TR 15310-1:2006, Clause 4)
2.8.1 General
One of the key activities in the development of a sampling plan is the consideration and selection of what can
collectively be regarded as the ‘statistical criteria’. The importance of this step is identified in 4.2.7 of
EN 14899:2005. Due consideration of these criteria ensures that appropriate boundaries are set for the
sampling exercise, and in particular that the type and number of samples taken will ensure that the data
collected is fit for purpose. Generally, the process identified in Figure 3 should be followed in the development
of any sampling plan.
Selecting sampling approach (2.9)

Define the population to be sampled (2.9.2.2)
Assess variability (2.9.2.3)
Identify the scale (2.9.2.4)
Choose the required statistical approach (2.9.2.5)
Choose the desired reliability (2.9.2.6)
Cho
...