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

SIGNIFICANCE AND USE
5.1 Assumptions of the Theis (1) equation affect specific capacity and transmissivity estimated from specific capacity. These assumptions are given below:  
5.1.1 Aquifer is homogeneous and isotropic.  
5.1.2 Aquifer is horizontal, of uniform thickness, and infinite in areal extent.  
5.1.3 Aquifer is confined by impermeable strata on its upper and lower boundaries.  
5.1.4 Density gradient in the flowing fluid must be negligible and the viscous resistance to flow must obey Darcy's Law.  
5.1.5 Control well penetrates and receives water equally from the entire thickness of the aquifer.  
5.1.6 Control well has an infinitesimal diameter.  
5.1.7 Control well discharges at a constant rate.  
5.1.8 Control well operates at 100 percent efficiency.  
5.1.9 Aquifer remains saturated throughout the duration of pumping.  
5.2 Implications of Assumptions and Limitations of Method.  
5.2.1 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.  
5.2.2 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.  
5.2.3 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.
Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performi...
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)2 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 scope of this test method is limited by the capabilities of the apparatus.  
1.6 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.6.1 The procedures used to specify how data are collected/recorded and calculated in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that should generally be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.  
1.7 The values stated in SI units are to be regarded as standard. Rationalized inch-pound units also are used in this standard. Each system of units is to be regarded separately as st...

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ASTM D5472/D5472M-14 - Standard Test Method for Determining Specific Capacity and Estimating Transmissivity at the Control Well
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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/D5472M −14
Standard Test Method for
Determining Specific Capacity and Estimating
1
Transmissivity at the Control Well
This standard is issued under the fixed designation D5472/D5472M; 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* this standard to consider significant digits used in analysis
methods for engineering design.
1.1 This test describes a procedure for conducting a specific
capacitytest,computingthespecificcapacityofacontrolwell, 1.7 The values stated in SI units are to be regarded as
and estimating the transmissivity in the vicinity of the control standard. Rationalized inch-pound units also are used in this
well. Specific capacity is the well yield per unit drawdown at standard. Each system of units is to be regarded separately as
an identified time after pumping started. standard.
1.2 This test method is used in conjunction with Test 1.8 This standard may involve hazardous materials,
Method D4050 for conducting withdrawal and injection well operations, and equipment. This standard does not address
tests. safety problems associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and
1.3 The method of determining transmissivity from specific
health practices and determine the applicability of regulatory
capacity is a variation of the nonequilibrium method of Theis
2 limitations prior to use.
(1) fordeterminingtransmissivityandstoragecoefficientofan
aquifer. The Theis nonequilibrium method is given in Test
2. Referenced Documents
Method D4106.
3
2.1 ASTM Standards:
1.4 Limitations—The limitations of the technique for deter-
D653Terminology Relating to Soil, Rock, and Contained
mining transmissivity are primarily related to the correspon-
Fluids
dence between the field situation and the simplifying assump-
D2488Practice for Description and Identification of Soils
tions of the Theis method.
(Visual-Manual Procedure)
1.5 The scope of this test method is limited by the capabili- D3740Practice for Minimum Requirements for Agencies
ties of the apparatus. Engaged in Testing and/or Inspection of Soil and Rock as
Used in Engineering Design and Construction
1.6 All observed and calculated values shall conform to the
D4050Test Method for (Field Procedure) for Withdrawal
guidelines for significant digits and rounding established in
and Injection Well Testing for Determining Hydraulic
Practice D6026.
Properties of Aquifer Systems
1.6.1 Theproceduresusedtospecifyhowdataarecollected/
D4106Test Method for (Analytical Procedure) for Deter-
recorded and calculated in this standard are regarded as the
mining Transmissivity and Storage Coefficient of Non-
industry standard. In addition, they are representative of the
leaky Confined Aquifers by the Theis Nonequilibrium
significant digits that should generally be retained. The proce-
Method
dures used do not consider material variation, purpose for
D6026Practice for Using Significant Digits in Geotechnical
obtaining the data, special purpose studies, or any consider-
Data
ations for the user’s objectives; and it is common practice to
increase or reduce significant digits of reported data to com-
3. Terminology
mensurate with these considerations. It is beyond the scope of
3.1 For common definitions of terms in this standard, refer
to Terminology D653.
1
ThistestmethodisunderthejurisdictionofASTMCommitteeD18onSoiland
3.2 Symbols and Dimensions:
Rock and is the direct responsibility of Subcommittee D18.21 on Groundwater and
−1
3.2.1 K—hydraulic conductivity [LT ]
Vadose Zone Investigations.
Current edition approved June 15, 2014. Published August 2014. Originally
approved in 1993. Last previous edition approved in 2005 as D5472–93(2005),
3
which was withdrawn February 2014 and reinstated in June 2014. DOI: 10.1520/ For referenced ASTM standards, visit the ASTM website, www.astm.org, or
D5472_D5472M-14. contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
2
The boldface numbers in parentheses refer to a list of references at the end of Standards volume information, refer to the standard’s Document Summary page on
this standard. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D5472/D5472M − 14
3.2.2 m—saturated thickness [L] 5.2.3 The values of transmissivity estimated from specific
3 −1
capacity data are considered less accurate than values obtained
3.2.3 Q—discharge [
...

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