ASTM D4104-96(2004)
(Test Method)Standard Test Method (Analytical Procedure) for Determining Transmissivity of Nonleaky Confined Aquifers by Overdamped Well Response to Instantaneous Change in Head (Slug Tests)
Standard Test Method (Analytical Procedure) for Determining Transmissivity of Nonleaky Confined Aquifers by Overdamped Well Response to Instantaneous Change in Head (Slug Tests)
SCOPE
1.1 This test method covers the determination of transmissivity from the measurement of force-free (overdamped) response of a well-aquifer system to a sudden change of water level in a well. Force-free response of water level in a well to a sudden change in water level is characterized by recovery to initial water level in an approximate exponential manner with negligible inertial effects.
1.2 The analytical procedure in this test method is used in conjunction with the field procedure in Test Method D 4044 for collection of test data.
1.3 LimitationsSlug tests are considered to provide an estimate of transmissivity. Although the assumptions of this test method prescribe a fully penetrating well (a well open through the full thickness of the aquifer), the slug test method is commonly conducted using a partially penetrating well. Such a practice may be acceptable for application under conditions in which the aquifer is stratified and horizontal hydraulic conductivity is much greater than vertical hydraulic conductivity. In such a case the test would be considered to be representative of the average hydraulic conductivity of the portion of the aquifer adjacent to the open interval of the well.
1.4 The values stated in SI units are to be regarded as standard.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D4104 – 96 (Reapproved 2004)
Standard Test Method
(Analytical Procedure) for Determining Transmissivity of
Nonleaky Confined Aquifers by Overdamped Well Response
to Instantaneous Change in Head (Slug Tests)
This standard is issued under the fixed designation D4104; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope D653 Terminology Relating to Soil, Rock, and Contained
Fluids
1.1 This test method covers the determination of transmis-
D4043 Guide for Selection of Aquifer Test Method in
sivity from the measurement of force-free (overdamped) re-
Determining Hydraulic Properties by Well Techniques
sponse of a well-aquifer system to a sudden change of water
D4044 Test Method for (Field Procedure) for Instantaneous
level in a well. Force-free response of water level in a well to
Change in Head (Slug) Tests for Determining Hydraulic
a sudden change in water level is characterized by recovery to
Properties of Aquifers
initial water level in an approximate exponential manner with
D4750 Test Method for Determining Subsurface Liquid
negligible inertial effects.
Levels in a Borehole or Monitoring Well (Observation
1.2 The analytical procedure in this test method is used in
Well)
conjunctionwiththefieldprocedureinTestMethodD4044for
D5912 TestMethodfor(AnalyticalProcedure)Determining
collection of test data.
Hydraulic Conductivity of an Unconfined Aquifer by
1.3 Limitations—Slug tests are considered to provide an
Overdamped Well Response to Instantaneous Change in
estimate of transmissivity. Although the assumptions of this
Head (Slug)
test method prescribe a fully penetrating well (a well open
through the full thickness of the aquifer), the slug test method
3. Terminology
is commonly conducted using a partially penetrating well.
3.1 Definitions:
Such a practice may be acceptable for application under
3.1.1 aquifer, confined—an aquifer bounded above and
conditions in which the aquifer is stratified and horizontal
below by confining beds and in which the static head is above
hydraulic conductivity is much greater than vertical hydraulic
the top of the aquifer.
conductivity. In such a case the test would be considered to be
3.1.2 confining bed—a hydrogeologic unit of less perme-
representative of the average hydraulic conductivity of the
able material bounding one or more aquifers.
portion of the aquifer adjacent to the open interval of the well.
3.1.3 control well—wellbywhichtheaquiferisstressed,for
1.4 The values stated in SI units are to be regarded as
example, by pumping, injection, or change of head.
standard.
3.1.4 head, static—theheightaboveastandarddatumofthe
1.5 This standard does not purport to address all of the
surface of a column of water (or other liquid) that can be
safety concerns, if any, associated with its use. It is the
supported by the static pressure at a given point.
responsibility of the user of this standard to establish appro-
3.1.5 hydraulic conductivity—(field aquifer tests), the vol-
priate safety and health practices and determine the applica-
umeofwaterattheexistingkinematicviscositythatwillmove
bility of regulatory limitations prior to use.
in a unit time under a unit hydraulic gradient through a unit
2. Referenced Documents area measured at right angles to the direction of flow.
3.1.6 observation well—a well open to all or part of an
2.1 ASTM Standards:
aquifer.
3.1.7 overdamped-well response—characterized by the wa-
ThistestmethodisunderthejurisdictionofASTMCommitteeD18onSoiland
ter level returning to the static level in an approximately
RockandisthedirectresponsibilityofSubcommitteeD18.21onGroundWaterand
exponential manner following a sudden change in water level.
Vadose Zone Investigations.
(See for comparison underdamped-well response.)
Current edition approved Nov. 1, 2004. Published December 2004. Originally
approved in 1991. Last previous edition approved in 1996 as D4104–96. DOI:
3.1.8 slug—avolumeofwaterorsolidobjectusedtoinduce
10.1520/D4104-96R04.
a sudden change of head in a well.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standardsvolume information, refer to the standard’s Document Summary page on
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D4104 – 96 (2004)
2 2
3.1.9 specific storage—the volume of water released from
a5 r S/r ,
w c
ortakenintostorageperunitvolumeoftheporousmediumper
b5 Tt/r ,
c
unit change in head.
and:
3.1.10 storage coeffıcient—the volume of water an aquifer
releases from or takes into storage per unit surface area of the
2 2
D~u! 5[uJ ~u! 22aJ ~u!# 1[uY ~u! 22aY ~u!#
0 1 0 1
aquifer per unit change in head. For a confined aquifer, the
NOTE 1—See D5912 and Hvorslev (2) Bouwer and Rice (3), and
storage coefficient is equal to the product of specific storage
Bouwer (4).
and aquifer thickness. For an unconfined aquifer, the storage
coefficient is approximately equal to the specific yield.
5. Significance and Use
3.1.11 transmissivity—the volume of water at the existing
kinematic viscosity that will move in a unit time under a unit
5.1 Assumptions of Solution of Cooper et al (1):
hydraulic gradient through a unit width of the aquifer.
5.1.1 Theheadchangeinthecontrolwellisinstantaneousat
3.1.12 underdamped-well response—responsecharacterized
time t =0.
by the water level oscillating about the static water level
5.1.2 Well is of finite diameter and fully penetrates the
following a sudden change in water level. (See for comparison
aquifer.
overdamped-well response.)
5.1.3 Flow in the nonleaky aquifer is radial.
3.1.13 For definitions of other terms used in this test
5.2 Implications of Assumptions:
method, see Terminology D653.
5.2.1 The mathematical equations applied ignore inertial
3.2 Symbols:
effects and assume the water level returns the static level in an
3.2.1 J [nd]—zero-order Bessel function of the first kind.
approximate exponential manner. The geometric configuration
3.2.2 J [nd]—first-order Bessel function of the first kind.
−1
of the well and aquifer are shown in Fig. 1.
3.2.3 K [LT ]—hydraulic conductivity.
2 −1
3.2.4 T [L T ]—transmissivity. 5.2.2 Assumptions are applicable to artesian or confined
3.2.5 S [nd]—storage coefficient.
conditions and fully penetrating wells. However, this test
3.2.6 Y [nd]—zero order Bessel function of the second method is commonly applied to partially penetrating wells and
kind.
in unconfined aquifers where it may provide estimates of
3.2.7 Y [nd]—first order Bessel function of the second hydraulic conductivity for the aquifer interval adjacent to the
kind.
open interval of the well if the horizontal hydraulic conduc-
3.2.8 r [L]—radius of control-well casing or open hole in tivity is significantly greater than the vertical hydraulic con-
c
interval where water level changes.
ductivity.
3.2.9 r [L]—radius of control well screen or open hole
w 5.2.3 AspointedoutbyCooperetal(1)thedeterminationof
adjacent to water bearing unit.
storage coefficient by this test method has questionable reli-
3.2.10 u—variable of integration.
ability because of the similar shape of the curves, whereas, the
3.2.11 H [L]—change in head in control well.
determination of transmissivity is not as sensitive to choosing
3.2.12 H [L]—initial head rise (or decline) in control well.
o the correct curve. However, the curve selected should not
3.2.13 t—time.
imply a storage coefficient unrealistically large or small.
3.2.14 b—Tt/r .
c
2 2
3.2.15 a—r S/r .
w c
4. Summary of Test Method
4.1 This test method describes the analytical procedure for
analyzing data collected during an instantaneous head (slug)
test using an overdamped well. The field procedures in
conducting a slug test are given in Test Method D4044. The
analytical procedure consists of analyzing the recovery of
water level in the well following the change in water level
induced in the well.
4.2 Solution—The solution given by Cooper et al (1) is as
follows:
`
2H
o 2
H 5 [@exp ~2bu /a!@J ~ur/r ! (1)
* 0 w
p
@uY ~u! 22aY ~u!# 2 Y ~ur/r !
0 1 0 w
@uJ ~u! 22aJ ~u!##/D~u!##du
0 1
where:
The boldface numbers in parentheses refer to a list of references at the end of FIG. 1 Cross Section Through a Well in Which a Slug of Water is
the text. Suddenly Injected
D4104 – 96 (2004)
6. Procedure 7. Calculation
6.1 The overall procedure consists of conducting the slug 7.1 Prepare a semilogarithmic plot of a set of type curves of
test field procedure (see Test Method D4044) and analysis of valuesof F(b, a)= H/H ,onthearithmeticscale,asafunction
o
the field data, t
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.