ASTM D5472-93(2005)
(Test Method)Standard Test Method for Determining Specific Capacity and Estimating Transmissivity at the Control Well (Withdrawn 2014)
Standard Test Method for Determining Specific Capacity and Estimating Transmissivity at the Control Well (Withdrawn 2014)
SIGNIFICANCE AND USE
Assumptions of the Theis (1) equation affect specific capacity and transmissivity estimated from specific capacity. These assumptions are given below:
Aquifer is homogeneous and isotropic.
Aquifer is horizontal, of uniform thickness, and infinite in areal extent.
Aquifer is confined by impermeable strata on its upper and lower boundaries.
Density gradient in the flowing fluid must be negligible and the viscous resistance to flow must obey Darcy's Law.
Control well penetrates and receives water equally from the entire thickness of the aquifer.
Control well has an infinitesimal diameter.
Control well discharges at a constant rate.
Control well operates at 100 percent efficiency.
Aquifer remains saturated throughout the duration of pumping.
Implications of Assumptions and Limitations of Method.
The simplifying assumptions necessary for solution of the Theis equation and application of the method are never fully met in a field test situation. The satisfactory use of the method may depend upon the application of one or more empirical correction factors being applied to the field data.
Generally the values of transmissivity derived from specific capacity vary from those values determined from aquifer tests utilizing observation wells. These differences may reflect 1) that specific-capacity represents the response of a small part of the aquifer near the well and may be greatly influenced by conditions near the well such as a gravel pack or graded material resulting from well development, and 2) effects of well efficiency and partial penetration.
The values of transmissivity estimated from specific capacity data are considered less accurate than values obtained from analysis of drawdowns that are observed some distance from the pumped well.
SCOPE
1.1 This test describes a procedure for conducting a specific capacity test, computing the specific capacity of a control well, and estimating the transmissivity in the vicinity of the control well. Specific capacity is the well yield per unit drawdown at an identified time after pumping started.
1.2 This test method is used in conjunction with Test Method D4050 for conducting withdrawal and injection well tests.
1.3 The method of determining transmissivity from specific capacity is a variation of the nonequilibrium method of Theis (1) for determining transmissivity and storage coefficient of an aquifer. The Theis nonequilibrium method is given in Test Method D4106.
1.4 Limitations—The limitations of the technique for determining transmissivity are primarily related to the correspondence between the field situation and the simplifying assumptions of the Theis method.
1.5 The values stated in SI units are to be regarded as standard.
1.6 This standard may involve hazardous materials, operations, and equipment. This standard does not address safety problems 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.
WITHDRAWN RATIONALE
This test describes a procedure for conducting a specific capacity test, computing the specific capacity of a control well, and estimating the transmissivity in the vicinity of the control well. Specific capacity is the well yield per unit drawdown at an identified time after pumping started.
Formerly under the jurisdiction of Committee D18 on Soil and Rock, this test method was withdrawn in February 2014 in accordance with section 10.6.3 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.
General Information
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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:D5472 −93(Reapproved 2005)
Standard Test Method for
Determining Specific Capacity and Estimating
Transmissivity at the Control Well
This standard is issued under the fixed designation D5472; 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 D4050Test Method for (Field Procedure) for Withdrawal
and Injection Well Tests for Determining Hydraulic Prop-
1.1 Thistestdescribesaprocedureforconductingaspecific
erties of Aquifer Systems
capacitytest,computingthespecificcapacityofacontrolwell,
D4106Test Method for (Analytical Procedure) for Deter-
and estimating the transmissivity in the vicinity of the control
mining Transmissivity and Storage Coefficient of Non-
well. Specific capacity is the well yield per unit drawdown at
leaky Confined Aquifers by the Theis Nonequilibrium
an identified time after pumping started.
Method
1.2 This test method is used in conjunction with Test
Method D4050 for conducting withdrawal and injection well 3. Terminology
tests.
3.1 Definitions:
1.3 The method of determining transmissivity from specific 3.1.1 aquifer, confined—an aquifer bounded above and be-
lowbyconfiningbedsandinwhichthestaticheadisabovethe
capacity is a variation of the nonequilibrium method of Theis
(1) for determining transmissivity and storage coefficient of an top of the aquifer.
aquifer. The Theis nonequilibrium method is given in Test
3.1.2 aquifer, unconfined—an aquifer that has a water table.
Method D4106.
3.1.3 control well—well by which the head and flow in the
1.4 Limitations—The limitations of the technique for deter-
aquifer is changed by pumping, injecting, or imposing a
mining transmissivity are primarily related to the correspon-
constant change of head.
dence between the field situation and the simplifying assump-
3.1.4 head, static—theheightaboveastandarddatumofthe
tions of the Theis method.
surfaceofacolumnofwaterthatcanbesupportedbythestatic
1.5 The values stated in SI units are to be regarded as pressure at a given point.
standard.
3.1.5 hydraulic conductivity—(fieldaquifertest)thevolume
1.6 This standard may involve hazardous materials, of water at the existing kinematic viscosity that will move in a
unit time under a unit hydraulic gradient through a unit area
operations, and equipment. This standard does not address
safety problems associated with its use. It is the responsibility measured at right angles to the direction of flow.
of the user of this standard to establish appropriate safety and
3.1.6 observation well—a well open to all or part of an
health practices and determine the applicability of regulatory
aquifer, and used to make measurements.
limitations prior to use.
3.1.7 specific capacity—well yield per unit drawdown at an
identified time after pumping started.
2. Referenced Documents
3.1.8 storage coeffıcient—the volume of water an aquifer
2.1 ASTM Standards:
releases from or takes into storage per unit surface area of the
D653Terminology Relating to Soil, Rock, and Contained
aquifer per unit change in head.
Fluids
3.1.9 transmissivity—the volume of water at the existing
kinematic viscosity that will move in a unit time under a unit
ThistestmethodisunderthejurisdictionofASTMCommitteeD18onSoiland
hydraulic gradient through a unit width of the aquifer.
Rock and is the direct responsibility of Subcommittee D18.21 on Groundwater and
Vadose Zone Investigations. 3.1.10 Fordefinitionsofothertermsusedinthismethodsee
Current edition approved Jan. 1, 2005. Published February 2005. Originally
Terminology, D653.
e1
approved in 1993. Last previous edition approved in 1999 as D5472–93(1999) .
3.2 Symbols and Dimensions:
DOI: 10.1520/D5472-93R05.
−1
2 3.2.1 K—hydraulic conductivity [LT ]
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
3.2.2 m—saturated thickness [L]
Standards volume information, refer to the standard’s Document Summary page on
3 −1
the ASTM website. 3.2.3 Q—discharge [L T ]
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5472−93 (2005)
3 −1 −1
3.2.4 Q/s—specific capacity [(L T )L ] 6. Conditioning Procedures
3.2.5 r—well radius [L]
6.1 Conditioningproceduresareconductedbeforethetestto
ensure that the control well is properly equipped and that the
3.2.6 s—drawdown [L]
well discharge and water-level measuring equipment is opera-
3.2.7 S—storage coefficient [dimensionless]
tional.
2 −1
3.2.8 T—transmissivity [L T ]
6.1.1 Equip the control well with a calibrated accumulating
2 −1
3.2.9 T`—provisional value of transmissivity [L T ]
water meter or another type of calibrated well yield measuring
device.
3.2.10 t—elapsed time of pumping [T]
2 6.1.2 Providethecontrolwellwithasystemformaintaining
3.2.11 u—r S/4Tt [dimensionless]
a constant discharge.
3.2.12 W(u)—well function of “u” [dimensionless]
6.1.3 Equip control well for measuring the pretest water
3.2.13 c — [W(u)/4π]
1 level (prepumping water level) and pumping water levels
during the specific capacity test.
4. Significance and Use
6.1.4 Measurestaticwaterlevelimmediatelybeforestarting
the pump.
4.1 Assumptions of the Theis (1) equation affect specific
6.1.5 Start pump and simultaneously measure elapsed time
capacity and transmissivity estimated from specific capacity.
with a stop watch or data recorder. After 3 to 5 minutes well
These assumptions are given below:
yield and drawdown should be measured and recorded.
4.1.1 Aquifer is homogeneous and isotropic.
6.1.6 If all the equipment is working properly, drawdown
4.1.2 Aquifer is horizontal, of uniform thickness, and infi-
measurements can be obtained, and constant discharge main-
nite in areal extent.
tained, the equipment check can be ended.
4.1.3 Aquiferisconfinedbyimpermeablestrataonitsupper
6.1.7 Ceasepumpingandallowthewaterleveltorecoverto
and lower boundaries.
itsprepumpinglevelbeforethespecificcapacitytestprocedure
4.1.4 Density gradient in the flowing fluid must be negli-
(Section 5) is initiated.
gible and the viscous resistance to flow must obey Darcy’s
Law.
4.1.5 Control well penetrates and receives water equally 7. Test Procedure
from the entire thickness of the aquifer.
7.1 Initiate well discharge.
4.1.6 Control well has an infinitesimal diameter.
7.2 Measure the well yield and pumping water level in the
4.1.7 Control well discharges at a constant rate.
control well at predetermined time intervals, for example, 2-,
4.1.8 Control well operates at 100 percent efficiency.
5-,10-,20-,30-,minutesafterdischargeisinitiated.Adjustthe
4.1.9 Aquifer remains saturated throughout the duration of
discharge rate during the test to maintain discharge within 5%
pumping.
of the rate planned.
4.2 Implications of Assumptions and Limitations of Method.
7.3 While test continues make the following calculations:
4.2.1 Thesimplifyingassumptionsnecessaryforsolutionof
7.3.1 Adjust drawdown for effects of desaturation of the
the Theis equation and application of the method are never
aquifer, if applicable (see Section 8).
fully met in a field test situation. The satisfactory use of the
7.3.2 Determine the specific capacity (see Section 10) and
method may depend upon the application of one or more
estimate transmissivity (see Section 11). If well bore storage
empirical correction factors being applied to the field data.
effectsarenegligible(seeSection9),comparethenewvalueof
4.2.2 Generally the values of transmissivity derived from
T`tothevalueusedtocalculate c ,ifthevalueiswithin10%,
specific capacity vary from those values determined from
the test can be terminated.
aquifertestsutilizingobservationwells.Thesedifferencesmay
reflect 1) that specific-capacity represents the response of a 7.3.3 If control well is not screened through the entire
thickness of the aquifer, estimate the transmissivity of the
small part of the aquifer near the well and may be greatly
influenced by conditions near the well such as a gravel pack or aquifer following procedure in Sections 11 and 12.
graded material resulting from well development, and 2)
effects of well efficiency and partial penetration. 8. Correction of Drawdown in an Unconfined Aquifer
4.2.3 The values of transmissivity estimated from specific
8.1 The Theis equation is directly applicable to confined
ca
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