ASTM D5785/D5785M-20
(Practice)Standard Practice for (Analytical Procedure) for Determining Transmissivity of Confined Nonleaky Aquifers by Underdamped Well Response to Instantaneous Change in Head (Slug Test)
Standard Practice for (Analytical Procedure) for Determining Transmissivity of Confined Nonleaky Aquifers by Underdamped Well Response to Instantaneous Change in Head (Slug Test)
SIGNIFICANCE AND USE
6.1 The assumptions of the physical system are given as follows:
6.1.1 The aquifer is of uniform thickness and confined by impermeable beds above and below.
6.1.2 The aquifer is of constant homogeneous porosity and matrix compressibility and of homogeneous and isotropic hydraulic conductivity.
6.1.3 The origin of the cylindrical coordinate system is taken to be on the well-bore axis at the top of the aquifer.
6.1.4 The aquifer is fully screened.
6.2 The assumptions made in defining the momentum balance are as follows:
6.2.1 The average water velocity in the well is approximately constant over the well-bore section.
6.2.2 Flow is laminar and frictional head losses from flow across the well screen are negligible.
6.2.3 Flow through the well screen is uniformly distributed over the entire aquifer thickness.
6.2.4 Change in momentum from the water velocity changing from radial flow through the screen to vertical flow in the well are negligible.
6.2.5 The system response is an exponentially decaying sinusoidal function.
Note 3: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
SCOPE
1.1 This practice covers determination of transmissivity from the measurement of the damped oscillation about the equilibrium water level of a well-aquifer system to a sudden change of water level in a well. Underdamped response of water level in a well to a sudden change in water level is characterized by oscillatory fluctuation about the static water level with a decrease in the magnitude of fluctuation and recovery to initial water level. Underdamped response may occur in wells tapping highly transmissive confined aquifers and in deep wells having long water columns.
1.2 This analytical procedure is used in conjunction with the field procedure Test Method D4044/D4044M for collection of test data.
1.3 Limitations—Slug tests are considered to provide an estimate of transmissivity of a confined aquifer. This test method requires that the storage coefficient be known. Assumptions of this practice prescribe a fully penetrating well (a well open through the full thickness of the aquifer), but 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. The method assumes laminar flow and is applicable for a slug test in which the initial water-level displacement is less than 0.1 or 0.2 of the length of the static water column.
1.4 This practice for analysis presented here is derived by van der Kamp (1)2 based on an approximation of the underdamped response to that of an exponentially damped sinusoid. A more rigorous analysis of the response of wells to a sudden change in water level by Kipp (2) indicates that the method presented by van der Kamp (1) matches the solution of Kipp (2) when the damping parameter values are less than about 0.2 and time greater than that of the first peak of the oscillation (2).
1.5 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values in each system may not be exact equivalents; therefore each system shall be used independe...
General Information
Buy Standard
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:D5785/D5785M −20
Standard Practice for
(Analytical Procedure) for Determining Transmissivity of
Confined Nonleaky Aquifers by Underdamped Well
1
Response to Instantaneous Change in Head (Slug Test)
This standard is issued under the fixed designation D5785/D5785M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* Amore rigorous analysis of the response of wells to a sudden
change in water level by Kipp (2) indicates that the method
1.1 This practice covers determination of transmissivity
presented by van der Kamp (1) matches the solution of Kipp
from the measurement of the damped oscillation about the
(2) when the damping parameter values are less than about 0.2
equilibrium water level of a well-aquifer system to a sudden
andtimegreaterthanthatofthefirstpeakoftheoscillation (2).
change of water level in a well. Underdamped response of
water level in a well to a sudden change in water level is
1.5 Units—The values stated in either SI units or inch-
characterized by oscillatory fluctuation about the static water
pound units are to be regarded separately as standard. The
level with a decrease in the magnitude of fluctuation and
values in each system may not be exact equivalents; therefore
recovery to initial water level. Underdamped response may
each system shall be used independently of the other. Combin-
occur in wells tapping highly transmissive confined aquifers
ing values from the two systems may result in non-
and in deep wells having long water columns.
conformance with the standard. Reporting of test results in
1.2 Thisanalyticalprocedureisusedinconjunctionwiththe
units other than SI shall not be regarded as nonconformance
field procedure Test Method D4044/D4044M for collection of
with this practice.
test data.
1.6 All observed and calculated values shall conform to the
1.3 Limitations—Slug tests are considered to provide an
guidelines for significant digits and rounding established in
estimate of transmissivity of a confined aquifer. This test
Practice D6026.
method requires that the storage coefficient be known. As-
sumptions of this practice prescribe a fully penetrating well (a
1.7 This practice offers a set of instructions for performing
wellopenthroughthefullthicknessoftheaquifer),buttheslug
one or more specific operations. This document cannot replace
test method is commonly conducted using a partially penetrat-
education or experience and should be used in conjunction
ing well. Such a practice may be acceptable for application
with professional judgment. Not all aspects of the practice may
under conditions in which the aquifer is stratified and horizon-
be applicable in all circumstances. This ASTM standard is not
talhydraulicconductivityismuchgreaterthanverticalhydrau-
intended to represent or replace the standard of care by which
lic conductivity. In such a case the test would be considered to
the adequacy of a given professional service must be judged,
be representative of the average hydraulic conductivity of the
nor should this document be applied without the consideration
portion of the aquifer adjacent to the open interval of the well.
of a project’s many unique aspects. The word “Standard” in
The method assumes laminar flow and is applicable for a slug
the title of this document means only that the document has
test in which the initial water-level displacement is less than
been approved through the ASTM consensus process.
0.1 or 0.2 of the length of the static water column.
1.8 This standard does not purport to address all of the
1.4 This practice for analysis presented here is derived by
2 safety concerns, if any, associated with its use. It is the
van der Kamp (1) based on an approximation of the under-
responsibility of the user of this standard to establish appro-
damped response to that of an exponentially damped sinusoid.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1
This practice is under the jurisdiction of ASTM Committee D18 on Soil and
1.9 This international standard was developed in accor-
Rock and is the direct responsibility of Subcommittee D18.21 on Groundwater and
dance with internationally recognized principles on standard-
Vadose Zone Investigations.
Current edition approved May 15, 2020. Published May 2020. Originally ization established in the Decision on Principles for the
approved in 1995. Last previous edition app
...
This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5785/D5785M − 15 D5785/D5785M − 20
Standard Test Method Practice for
(Analytical Procedure) for Determining Transmissivity of
Confined Nonleaky Aquifers by Underdamped Well
1
Response to Instantaneous Change in Head (Slug Test)
This standard is issued under the fixed designation D5785/D5785M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This test method covers determination of transmissivity from the measurement of the damped oscillation about the
equilibrium water level of a well-aquifer system to a sudden change of water level in a well. Underdamped response of water level
in a well to a sudden change in water level is characterized by oscillatory fluctuation about the static water level with a decrease
in the magnitude of fluctuation and recovery to initial water level. Underdamped response may occur in wells tapping highly
transmissive confined aquifers and in deep wells having long water columns.
1.2 This analytical procedure is used in conjunction with the field procedure Test Method D4044 for collection of test data.
1.3 Limitations—Slug tests are considered to provide an estimate of transmissivity of a confined aquifer. This test method
requires that the storage coefficient be known. Assumptions of this test method prescribe a fully penetrating well (a well open
through the full thickness of the aquifer), but 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. The method assumes
laminar flow and is applicable for a slug test in which the initial water-level displacement is less than 0.1 or 0.2 of the length of
the static water column.
2
1.4 This test method of analysis presented here is derived by van der Kamp (1) based on an approximation of the underdamped
response to that of an exponentially damped sinusoid. A more rigorous analysis of the response of wells to a sudden change in water
level by Kipp (2) indicates that the method presented by van der Kamp (1) matches the solution of Kipp (2) when the damping
parameter values are less than about 0.2 and time greater than that of the first peak of the oscillation (2).
1.5 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values in each
system may not be exact equivalents; therefore each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the standard. Reporting of test results in units other than SI shall not be regarded
as nonconformance with this test method.
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice
D6026.
1.7 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.
2. Referenced Documents
3
2.1 ASTM Standards:
D653 Terminology Relating to Soil, Rock, and Contained Fluids
1
This test method practice is under the jurisdiction of ASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.21 on Groundwater
and Vadose Zone Investigations.
Current edition approved Nov. 1, 2015May 15, 2020. Published November 2015May 2020. Originally approved in 1995. Last previous edition approved in 20132015 as
D5785 – 95 (2013).D5785 – 15. DOI: 10.1520/D5785_D5785M-15.10.1520/D5785_D5785M-20.
2
The boldface numbers given in parentheses refer to a list of references at the end of the text.
3
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 Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © AST
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.