ASTM D5472-93(1999)e1

Standard Test Method for Determining Specific Capacity and Estimating Transmissivity at the Control 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.

General Information

• Status: Historical
• Publication Date: 09-Jun-1999
• ICS: 13.060.10 - Water of natural resources
• Technical Committee: D18 - Soil and Rock
• Drafting Committee: D18.21 - Groundwater and Vadose Zone Investigations

Relations

• Replaced By: ASTM D5472-93(2005) - Standard Test Method for Determining Specific Capacity and Estimating Transmissivity at the Control Well (Withdrawn 2014)
• Effective Date: 01-Jan-2005
• Referred By: ASTM D6000/D6000M-15e1 - Standard Guide for Presentation of Water-Level Information from Groundwater Sites (Withdrawn 2024)
• Effective Date: 10-Jun-1999
• Referred By: ASTM D4043-17 - Standard Guide for Selection of Aquifer Test Method in Determining Hydraulic Properties by Well Techniques
• Effective Date: 10-Jun-1999
• Referred By: ASTM D5978/D5978M-16 - Standard Guide for Maintenance and Rehabilitation of Groundwater Monitoring Wells
• Effective Date: 10-Jun-1999

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
e1
Designation: D 5472 – 93 (Reapproved 1999)
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 (e) indicates an editorial change since the last revision or reapproval.
e NOTE—Section 10.2.1 was corrected editorially in August 1999.
1. Scope D4106 TestMethodforAnalyticalProcedureforDetermin-
ing Transmissivity and Storativity of Nonleaky Confined
1.1 This test describes a procedure for conducting a specific
Aquifers by the Theis Nonequilibrium Method
capacitytest,computingthespecificcapacityofacontrolwell,
D4750 Test Method for Determining Subsurface Liquid
and estimating the transmissivity in the vicinity of the control
Levels in a Borehole or Monitoring Well
well. Specific capacity is the well yield per unit drawdown at
an identified time after pumping started.
3. Terminology
1.2 This test method is used in conjunction with Test
3.1 Definitions:
Method D4050 for conducting withdrawal and injection well
3.1.1 aquifer, confined—an aquifer bounded above and
tests.
below by confining beds and in which the static head is above
1.3 The method of determining transmissivity from specific
the top of the aquifer.
capacity is a variation of the nonequilibrium method of Theis
3.1.2 aquifer, unconfined—an aquifer that has a water table.
(1) for determining transmissivity and storage coefficient of an
3.1.3 control well—well by which the head and flow in the
aquifer. The Theis nonequilibrium method is given in Test
aquifer is changed by pumping, injecting, or imposing a
Method D4106.
constant change of head.
1.4 Limitations—The limitations of the technique for deter-
3.1.4 head, static—theheightaboveastandarddatumofthe
mining transmissivity are primarily related to the correspon-
surfaceofacolumnofwaterthatcanbesupportedbythestatic
dence between the field situation and the simplifying assump-
pressure at a given point.
tions of the Theis method.
3.1.5 hydraulic conductivity—(fieldaquifertest)thevolume
1.5 The values stated in SI units are to be regarded as
of water at the existing kinematic viscosity that will move in a
standard.
unit time under a unit hydraulic gradient through a unit area
1.6 This standard may involve hazardous materials, opera-
measured at right angles to the direction of flow.
tions, and equipment. This standard does not address safety
3.1.6 observation well—a well open to all or part of an
problems associated with its use. It is the responsibility of the
aquifer, and used to make measurements.
user of this standard to establish appropriate safety and health
3.1.7 specific capacity—well yield per unit drawdown at an
practices and determine the applicability of regulatory limita-
identified time after pumping started.
tions prior to use.
3.1.8 storage coeffıcient—the volume of water an aquifer
2. Referenced Documents releases from or takes into storage per unit surface area of the
aquifer per unit change in head.
2.1 ASTM Standards:
3.1.9 transmissivity—the volume of water at the existing
D653 Terminology Relating to Soil, Rock, and Contained
kinematic viscosity that will move in a unit time under a unit
Fluids
hydraulic gradient through a unit width of the aquifer.
D4050 Test Method (Field Procedure) for Withdrawal and
3.1.10 Fordefinitionsofothertermsusedinthismethodsee
Injection Well Tests for Determining Hydraulic Properties
Terminology, D653.
of Aquifer Systems
3.2 Symbols:Symbols and Dimensions:
−1
3.2.1 K—hydraulic conductivity [LT ]
3.2.2 m—saturated thickness [L]
1 3 −1
This test method is under the jurisdiction of ASTM Committee D-18 on Soil
3.2.3 Q—discharge [L T ]
andRockandisthedirectresponsibilityofSubcommitteeD18.21onGroundWater 3 −1 −1
3.2.4 Q/s—specific capacity [(L T )L ]
and Vadose Zone Investigations.
3.2.5 r—well radius [L]
Current edition approved Nov. 15, 1993. Published January 1994.
Annual Book of ASTM Standards, Vol 04.08. 3.2.6 s—drawdown [L]
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D 5472
3.2.7 S—storage coefficient [dimensionless] 6.1.1 Equip the control well with a calibrated accumulating
2 −1
3.2.8 T—transmissivity [L T ] water meter or another type of calibrated well yield measuring
2 −1
3.2.9 T8—provisional value of transmissivity [L T ] device.
3.2.10 t—elapsed time of pumping [T] 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)/4p] 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.
7. Test Procedure
4.1.5 Control well penetrates and receives water equally
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 T8 to the value used to calculate c , if the value is within 10%,
specific capacity vary from those values determined from the test can be terminated.
aquifertestsutilizingobservationwells.Thesedifferencesmay 7.3.3 If control well is not screened through the entire
reflect 1) that specific-capacity represents the response of a thickness of the aquifer, estimate the transmissivity of the
small part of the aquifer near the well and may be greatly aquifer following procedure in Sections 11 and 12.
influenced by conditions near the well such as a gravel pack or
graded material resulting from well development, and 2)
8. Correction of Drawdown in an Unconfined Aquifer
effects of well efficiency and partial penetration.
8.1 The Theis equation is directly applicable to confined
4.2.3 The values of transmissivity estimated from specific
aquifers and is suitable for use with limitations in unconfined
capacity data are considered less accurate than values obtained
aquifers.Iftheaquiferisunconfinedanddrawdownislessthan
from analysis of drawdowns that are observed some d
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