SIST EN ISO 22282-4:2012
(Main)Geotechnical investigation and testing - Geohydraulic testing - Part 4: Pumping tests (ISO 22282-4:2012)
Geotechnical investigation and testing - Geohydraulic testing - Part 4: Pumping tests (ISO 22282-4:2012)
This part of ISO 22282 establishes requirements for pumping tests as part of geotechnical investigation service in accordance with EN 1997-1 and EN 1997-2. A pumping test consists in principle of: - drawing down the piezometric surface of the groundwater by pumping from a well (the test well); - measuring the pumped discharge and the water level in the test well and piezometers, before, during and after pumping, as a function of time. This part of ISO 22282 applies to pumping tests performed on aquifers whose permeability is such that pumping from a well can create a lowering of the piezometric head within hours or days depending on the ground conditions and the purpose. It covers pumping tests carried out in soils and rock.
Geotechnische Erkundung und Untersuchung - Geohydraulische Versuche - Teil 4: Pumpversuche (ISO 22282-4:2012)
Die vorliegende Norm behandelt Anforderungen an Pumpversuche als Teil des geotechnischen Erkundungsdienstes nach EN 1997-1 und EN 1997-2. Grundsätzlich besteht ein Pumpversuch aus Folgendem:
- Absenken der Piezometeroberfläche des Grundwassers durch Abpumpen von Wasser aus einem Brunnen (dem Versuchsbrunnen);
- Messen der abgepumpten Menge (Abfluss) und des Wasserspiegels im Versuchsbrunnen und in den Piezometern vor, während und nach dem Pumpen als Funktion der Zeit. Dieser Teil von ISO 22282 gilt für Pumpversuche an Grundwasserleitern, deren Durchlässigkeit so ist, dass das Abpumpen aus einem Brunnen – in Abhängigkeit von den Bedingungen des Baugrunds und dem Zweck – zu einer Absenkung der piezometrischen Höhe innerhalb von Stunden oder Tagen führt. Das Dokument behandelt Pumpversuche in Böden und Fels. Bei den durch diesen Teil von ISO 22282 abgedeckten Versuchen handelt es sich um diejenigen, die zur Bewertung der hydrodynamischen Parameter eines Grundwasserleiters und von Brunnenparametern vorgesehen sind, z. B.:
- allgemeine Durchlässigkeit des Grundwasserleiters;
- Einflussradius des Pumpens;
- Förderrate für einen Brunnen;
- Ansprechen in Bezug auf die Absenkung in einem Grundwasserleiter während des Pumpens;
- Skin-Effekt;
- Brunnenspeicherung,
- Ansprechen in Bezug auf die Wiederherstellung in einem Grundwasserleiter nach dem Pumpen.
Reconnaissance et essais géotechniques - Essais géohydrauliques - Partie 4: Essais de pompage (ISO 22282-4:2012)
Geotehnično preiskovanje in preskušanje - Hidrogeološke preiskave - 4. del: Črpalni preskus (ISO 22282-4:2012)
Ta del standarda ISO 22282 vzpostavlja zahteve za preizkuse črpanja kot del geotehničnih raziskovalnih storitev v skladu s standardoma EN 1997-1 in EN 1997-2. Preizkus črpanja sestavljata predvsem: – spuščanje piezometrične površine podtalnice s črpanjem iz vrtine (preizkusne vrtine); – merjenje pretoka črpanja in ravni vode v preizkusni vrtini in piezometrih pred in med črpanjem ter po njem, v časovni odvisnosti. Ta del standarda ISO 22282 velja za preizkuse črpanja, izvedene v vodonosnikih, katerih propustnost je tolikšna, da lahko črpanje iz vrtine povzroči znižanje piezometrične gladine v nekaj urah ali dneh, odvisno od pogojev tal in namena. Pokriva preizkuse črpanja, izvedene v prsti in kamninah.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 22282-4:2012
01-december-2012
*HRWHKQLþQRSUHLVNRYDQMHLQSUHVNXãDQMH+LGURJHRORãNHSUHLVNDYHGHO
ýUSDOQLSUHVNXV ,62
Geotechnical investigation and testing - Geohydraulic testing - Part 4: Pumping tests
(ISO 22282-4:2012)
Geotechnische Erkundung und Untersuchung - Geohydraulische Versuche - Teil 4:
Pumpversuche (ISO 22282-4:2012)
Reconnaissance et essais géotechniques - Essais géohydrauliques - Partie 4: Essais de
pompage (ISO 22282-4:2012)
Ta slovenski standard je istoveten z: EN ISO 22282-4:2012
ICS:
93.020 Zemeljska dela. Izkopavanja. Earthworks. Excavations.
Gradnja temeljev. Dela pod Foundation construction.
zemljo Underground works
SIST EN ISO 22282-4:2012 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 22282-4:2012
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SIST EN ISO 22282-4:2012
EUROPEAN STANDARD
EN ISO 22282-4
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2012
ICS 93.020
English Version
Geotechnical investigation and testing - Geohydraulic testing -
Part 4: Pumping tests (ISO 22282-4:2012)
Reconnaissance et essais géotechniques - Essais Geotechnische Erkundung und Untersuchung -
géohydrauliques - Partie 4: Essais de pompage (ISO Geohydraulische Versuche - Teil 4: Pumpversuche (ISO
22282-4:2012) 22282-4:2012)
This European Standard was approved by CEN on 31 May 2012.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, 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. EN ISO 22282-4:2012: E
worldwide for CEN national Members.
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SIST EN ISO 22282-4:2012
EN ISO 22282-4:2012 (E)
Contents Page
Foreword .3
2
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SIST EN ISO 22282-4:2012
EN ISO 22282-4:2012 (E)
Foreword
This document (EN ISO 22282-4:2012) has been prepared by Technical Committee CEN/TC 341
“Geotechnical Investigation and Testing", the secretariat of which is held by ELOT, in collaboration with
Technical Committee ISO/TC 182 "Geotechnics".
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by December 2012, and conflicting national standards shall be withdrawn
at the latest by December 2012.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland, Turkey and the United Kingdom.
3
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SIST EN ISO 22282-4:2012
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SIST EN ISO 22282-4:2012
INTERNATIONAL ISO
STANDARD 22282-4
First edition
2012-06-01
Geotechnical investigation and testing —
Geohydraulic testing —
Part 4:
Pumping tests
Reconnaissance et essais géotechniques — Essais géohydrauliques —
Partie 4: Essais de pompage
Reference number
ISO 22282-4:2012(E)
©
ISO 2012
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and symbols . 2
3.1 Terms and definitions . 2
3.2 Symbols . 2
4 Equipment . 2
5 Test procedure . 3
5.1 Test preparation . 3
5.2 Arranging the disposal of discharge water . 3
5.3 Executing and equipping the well . 4
5.4 Executing and equipping the piezometers . 6
5.5 Execution of the test . 6
5.6 Uncertainty of measurement . 9
5.7 Interruptions in pumping . 9
5.8 Decommissioning . 9
6 Test results . 9
7 Reports .10
7.1 Field report .10
7.2 Test report . 11
Annex A (informative) Record of measured values and test results of the pumping test — Example .12
Annex B (informative) Determining the pumping test discharge .14
Annex C (informative) Interpretation of the pumping test results .18
Bibliography .25
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(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. Each 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 part in the work. ISO collaborates closely with the International
Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. 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.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 22282-4 was prepared by the European Committee for Standardization (CEN) Technical Committee
CEN/TC 341, Geotechnical investigation and testing, in collaboration with Technical Committee ISO/TC 182,
Geotechnics, Subcommittee SC 1, Geotechnical investigation and testing, in accordance with the Agreement
on technical cooperation between ISO and CEN (Vienna Agreement).
ISO 22282 consists of the following parts, under the general title Geotechnical investigation and testing —
Geohydraulic testing:
— Part 1: General rules
— Part 2: Water permeability tests in a borehole using open systems
— Part 3: Water pressure tests in rock
— Part 4: Pumping tests
— Part 5: Infiltrometer tests
— Part 6: Water permeability tests in a borehole using closed systems
iv © ISO 2012 – All rights reserved
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SIST EN ISO 22282-4:2012
INTERNATIONAL STANDARD ISO 22282-4:2012(E)
Geotechnical investigation and testing — Geohydraulic testing —
Part 4:
Pumping tests
1 Scope
This part of ISO 22282 establishes requirements for pumping tests as part of geotechnical investigation service
in accordance with EN 1997-1 and EN 1997-2.
A pumping test consists in principle of:
— drawing down the piezometric surface of the groundwater by pumping from a well (the test well);
— measuring the pumped discharge and the water level in the test well and piezometers, before, during and
after pumping, as a function of time.
This part of ISO 22282 applies to pumping tests performed on aquifers whose permeability is such that
pumping from a well can create a lowering of the piezometric head within hours or days depending on the
ground conditions and the purpose. It covers pumping tests carried out in soils and rock.
The tests concerned by this part of ISO 22282 are those intended for evaluating the hydrodynamic parameters
of an aquifer and well parameters, such as:
— permeability of the aquifer,
— radius of influence of pumping,
— pumping rate of a well,
— response of drawdown in an aquifer during pumping,
— skin effect,
— well storage,
— response of recovery in an aquifer after pumping.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced document
(including any amendments) applies
ISO 14688-1, Geotechnical investigation and testing — Identification and classification of soil — Part 1:
Identification and description
ISO 14689-1, Geotechnical investigation and testing — Identification and classification of rock — Part 1:
Identification and description
ISO 22282-1, Geotechnical investigation and testing — Geohydraulic testing — General rules
ISO 22475-1, Geotechnical investigation and testing — Sampling methods and groundwater measurements —
Part 1: Technical principles for execution
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(E)
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 22282-1 and the following apply.
3.1.1
radius of influence of pumping
R(t)
distance, measured from the axis of the well, beyond which the lowering of the piezometric surface of the
groundwater is nil
NOTE In a steady-state condition, R(t) is constant, and is thus designated by R .
a
3.2 Symbols
Symbol Designation Unit
D drilled diameter of the well m
d thickness of the aquifer m
L
wetted length of screen of the perforated pipe placed in the well m
3
Q flow rate m /s
3
Q discharge rate, assessed pumping discharge at the end of the well preparation m /s
d
3
Q discharge of the pumping test m /s
e
R radius of influence under steady-state conditions m
a
R(t) radius of influence at time (t) m
S storage factor —
2
T transmissivity m /s
t time s
v
velocity —
a
slope of the line that characterizes the drawdown in the well —
b ordinate at the origin of the line that characterizes the drawdown in the well —
c conventional drawdown unit of the preliminary pump discharge —
d size which may be interpolated from the grading curve, of the square sieve mesh of side —
N
d for which the weight percent of undersize is equal to N percent
e
distance between the bottom of the well and the surface of the unconfined groundwater m
at rest in an aquifer
k horizontal permeability coefficient m/s
h
Dh drawdown of the water level in the well m
Dh’ drawdown of the water level in the well after 2 h m
Dh drawdown of the water level in the well, set during the preliminary test and not to be m
f
exceeded
Dh maximum drawdown of the water level in the well during the pumping test m
max
4 Equipment
Conducting a pumping test requires the following equipment and instruments:
a) a test well and piezometers (see ISO 22475-1);
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(E)
b) a pump and associated pipework capable of pumping from the test well. The pumps shall be equipped with
a suitably long discharge pipe so that the water from the pump is discharged sufficiently far away so that it
does not affect the test area. The capacity of the pump shall be sufficient to extract from the well a discharge
at least equal to that corresponding to that estimated to achieve the maximum planned drawdown;
NOTE Pumping tests are commonly carried out using electric submersible pumps, installed within the test well.
However, depending on conditions, pumping tests can also be carried out using suction pumps located at the surface,
airlift equipment, or special dewatering equipment such as wellpoints or eductors.
3
c) a system for regulating and measuring the discharge (m /s). Devices for measuring the discharge rate
shall be suitably calibrated and shall be accurate for a range of flow rates anticipated during the test;
d) a system for measuring the water level in the test well and piezometers. The turbulence in the test well
caused by pumping shall be considered; the devices shall be capable of measuring water levels over the
range of drawdowns anticipated during the test;
e) a time measuring and/or recording device, reading in seconds.
5 Test procedure
5.1 Test preparation
5.1.1 General
When preparing a pumping test, there are a number of things to investigate and consider in advance, such as:
— basic information on the ground and groundwater conditions according to ISO 22282-1;
— the required drawdown and/or the required discharge rate during the test;
— the discharge point for the pumped water and its location relative to the test well;
— the duration of the test.
5.1.2 Determining the discharge rate for the pumping test
The discharge rate Q must be estimated to ensure that the test well can yield sufficient water, to allow a pump of
d
appropriate capacity to be selected, and to ensure that the discharge can be accepted at the agreed disposal point.
The discharge rate can be estimated by one or more of the following methods:
— based on the purpose of the test and experience of local conditions;
— by theoretical assessment of the well capacity, according to the method described in Annex B;
— by analysis of information from the preliminary pumping phase, according to the method described in Annex B.
5.2 Arranging the disposal of discharge water
The disposal of discharge water shall be in accordance with relevant rules and regulations.
If the discharge water is not disposed of via an engineered sewer network, it shall be disposed of at sufficient
distance from the test well that it will not have a significant impact on the observed pattern of groundwater lowering.
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(E)
5.3 Executing and equipping the well
5.3.1 Design of the test well
The test well shall be designed to satisfy the following criteria (see Figure 1):
— of sufficient depth to penetrate below the groundwater level in the strata of interest. If the test well does not
fully penetrate the aquifer, it shall penetrate the saturated part of the aquifer to a depth of at least 25 times
the well screen diameter with a minimum of 3 m;
— of sufficient drilled diameter to accommodate the necessary filter materials and well screen of sufficient
diameter to accommodate pumping equipment of adequate capacity to achieve the required discharge rate;
— with sufficient length and capacity of well screen to ensure that the required discharge rate can be achieved;
— to have appropriate filter material to ensure that the discharge water contains an acceptably low sediment
content to avoid the risk of pump damage and ground settlement as a result of the removal of fine particles
from the soil. Where the well is constructed in a stable rock, it may be possible to construct a test well
without the need for filter material.
The filter material shall be a highly permeable granular material of closely controlled particle size, and be
formed of grains of inert minerals in relation to the aquifer groundwater chemistry (e.g. quartz, feldspar). In
granular soils, the filter’s grading curve shall satisfy the double inequality:
5 d ≤ d ≤ 5 d
15 soil 15 filter 85 soil
where d designates the characteristic size of the filter or of the ground in place, such that the mass of the soil
N
fraction passing through a sieve with a square mesh of side d represents N % of the total mass of material.
In fine grained soils or where the well screen is equipped with a geotextile mesh designed to act as a filter, the
filter material’s purpose is to backfill the annular space between the outside of the well screen and the borehole
wall. In those circumstances the filter media should be highly permeable coarse sand or fine gravel, with a
permeability coefficient at least 100 times that of the soil or rock being tested.
The thickness of the annular space for the filter pack shall be at least 50 mm. The inner diameter of the test well
shall be selected according to the purpose.
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(E)
Key
1 well screen (slotted tube)
2 filter material (filter pack)
3 submersible pump
4 borehole casing
5 tube for measuring the water level
6 sealing plug
7 plain tube
8 device for measuring the water level
9 base of the screen
L filter length
D drilled diameter of the well
Figure 1 — Test well equipped for a pumping test — Example
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(E)
5.3.2 Installation procedure
The test well shall be constructed in a similar way to piezometers in accordance with ISO 22475-1. Great care
shall be taken when installing the well materials. Particular attention shall be paid to the following:
— The well screen shall be lowered into the borehole to the specified level and shall be installed centrally in
the well, with the top and bottom of the screen located at the design level. Care shall be taken that the joints
of the screen and casing do not leak, and that the screen and casing are installed vertically and straight.
— If necessary, filter material shall be inserted in the annular space between the screen and the temporary
casing (or borehole wall). The filter material shall be placed progressively in stages to reduce the risk of a
blockage in the annular space. The filter material shall preferably be placed via a tremie pipe.
— If necessary, a sealing plug of low permeability material (such as bentonite) shall be created in the annular
space between the borehole wall and the well casing immediately above the filter material. The purpose of
the sealing plug is to prevent infiltration of surface water, or water from other aquifers, into the well screen.
5.3.3 Preparation of the well
Prior to the pumping test the well shall be developed to increase the permeability of the soil around the shell
by washing, and to remove any drilling residues and mobile soil particles that could be entrained by the water
flow into the well. Such particles could clog the filter and damage the test pump.
Development shall be carried out by means of pumping. Possible methods include airlifting or pumping using a
robust pump that is not damaged by the presence of particles in the discharge water. If airlift pumping is used,
care shall be taken to avoid injecting air into the ground, as air bubbles in the ground can affect the permeability.
Other methods for well development may be used in combination with pumping, including:
— jetting with water inside the well screen;
— surging or swabbing inside the well screen to induce water flow into and out of the well;
— chemical treatment (e.g. use of acids in carbonate rocks).
5.4 Executing and equipping the piezometers
5.4.1 Installation procedure
Piezometers shall be installed in accordance with ISO 22475-1.
The piezometer tubes shall be installed at such a depth that the influence of the test well can be observed and
recorded adequately. Where possible, the piezometer closest to the test well shall be located at the same depth
as the bottom of the test well.
5.4.2 Preparation of piezometers
Before commencement of the test, piezometers shall be cleaned in accordance with ISO 22475-1. The water level
in the piezometers shall be measured for a period before and after the test in order to find any natural variations
in the groundwater level. Their response time shall be checked by watching the water rise in the piezometer tube.
The period of monitoring depends on the nature of the aquifer and the purpose of the pumping test.
5.5 Execution of the test
5.5.1 General
The test comprises up to four phases:
— a pre-pumping phase to monitor the undisturbed groundwater levels;
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(E)
— a preliminary pumping phase to determine the discharge from the pumping test;
— the pumping test phase;
— the post-pumping test phase to monitor recovery of groundwater levels.
5.5.2 Pre-pumping monitoring
Prior to commencement of the pumping phase of the test, water levels in the test well and piezometers shall be
monitored to determine natural groundwater levels.
NOTE The duration of the pre-pumping phase depends on the purpose of the test and local conditions. Typical
durations of pre-pumping monitoring are between one day and ten days. Longer periods of pre-pumping monitoring are
necessary when groundwater levels are subject to tidal or other variations.
5.5.3 Preliminary pumping phase
Prior to the main pumping test a short period of pumping shall be carried out to test the equipment.
NOTE Suitable durations for the equipment test are between 15 min and 2 h.
During the preliminary pumping phase the correct functioning of pumps, control systems, valves, flow
measurement devices and water level measurement devices shall be checked. Discharge pipe work shall
be checked for leaks. Any corrective action deemed necessary shall be taken prior to commencement of the
pumping test.
For large-scale or complex pumping tests, the preliminary pumping phase can be used to provide information
on discharge rate and drawdown to assist in determination of discharge rate for the pumping test (see Annex B).
5.5.4 Pumping test
The pumping test shall not be started until water levels in the test well and the piezometers have stabilized
following the preliminary pumping phase.
The pumping test can comprise:
— a variable rate test. This type of test involves pumping the test well in a step-wise fashion, either increasing
or decreasing, up to the maximum capacity of the test well or the pump. A variable rate test can be used
to assist in determination of the discharge rate for a constant rate test;
and/or
— a constant rate test. This type of test involves pumping the test well at a constant rate for the duration on the test.
If the pumping test comprises a variable rate test followed by a constant rate test, there may be a period of
post pumping monitoring following the end of the variable rate test. In this case, the period between the end of
the variable rate test and the beginning of the constant rate test should be long enough to allow water levels
to stabilize.
Whenever the discharge is started or changed, the change in pumping rate shall be carried out rapidly. At the
start of the pumping test the discharge rate shall be stabilized within 2 min after starting the pumping.
The time at the start of the test is defined as t = 0.
During the pumping test measurements of water level shall be made according to the requirements of the
purpose of the test and the ground conditions. In general, measurements shall be taken more frequently at the
start of the pumping test, or when flow rate has been changed during a variable rate test, when water levels are
likely to be changing rapidly. During the later stages of a pumping test, when water levels are changing more
slowly, readings can be taken less frequently.
The following time increments between readings should be used unless alternative time increments can be
justified based on the purpose of the test and the ground conditions. If the groundwater levels in the test well
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SIST EN ISO 22282-4:2012
ISO 22282-4:2012(E)
and piezometers are likely to continue to change at a significant rate, it may be necessary to take readings
more frequently than the guidelines below:
— ≤ 30 s for t ≤ 5 min;
— ≤ 1 min for t = 5 min to 15 min;
— ≤ 5 min for t = 15 min to 30 min;
— ≤ 10 min for t = 30 min to 1 h;
— ≤ 30 min for t = 1 h to 4 h;
— ≤ 1 h for t > 4 h.
Where a pumping test is carried out in conditions where groundwater is subject to tidal variations, water
level readings shall be taken at frequent intervals throughout the test duration. In tidal conditions the interval
between readings should not exceed 15 min.
The pump discharge shall be measured at least four times in the first hour. If the discharge is stable, the discharge
can be measured once a day. If the discharge is not stable, the pump discharge shall be determined each hour.
Levels of open water bodies in the vicinity of the test site, where variation is likely to interfere with the pumping
test (and vice versa), shall be recorded periodically throughout the test.
Pumping shall be continued until the end of the specified pump test period or, if the test is required to achieve
steady-state conditions, until three successive readings, spaced at least 1 h apart, of
...
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